Sample records for photon number statistics

  1. Using a qubit to measure photon number statistics of a driven, thermal oscillator

    E-print Network

    A. A. Clerk; D. Wahyu Utami

    2006-12-09

    We demonstrate theoretically how photon number statistics of a driven, damped oscillator at finite temperature can be extracted by measuring the dephasing spectrum of a two-level system dispersively coupled to the oscillator; we thus extend the work of Dykman (1987) and Gambetta et al. (2006). We carefully consider the fidelity of this scheme-- to what extent does the measurement reflect the initial number statistics of the mode? We also derive analytic results for the dephasing of a qubit by a driven, thermal mode, and compare results obtained at different levels of approximation. Our results have relevance both to experiments in circuit cavity QED, as well as to nano-electromechanical systems.

  2. Using a qubit to measure photon number statistics of a driven, thermal oscillator

    Microsoft Academic Search

    Aashish Clerk; Dian Wahyu Utami

    2007-01-01

    We demonstrate theoretically how photon number statistics of a driven, damped oscillator at finite temperature can be extracted by measuring the dephasing spectrum of a two-level system dispersively coupled to the oscillator; previous results only dealt with the purely thermal or zero-temperature driven cases [1][2]. We also consider the fidelity of this scheme-- to what extent does the measurement reflect

  3. Using a qubit to measure photon-number statistics of a driven thermal oscillator A. A. Clerk and D. Wahyu Utami

    E-print Network

    Clerk, Aashish

    theoretically how photon-number statistics of a driven damped oscillator at finite tempera- ture canUsing a qubit to measure photon-number statistics of a driven thermal oscillator A. A. Clerk and D be extracted by measuring the dephasing spectrum of a two-level system dispersively coupled to the oscillator

  4. The statistical distribution of the number of counted scintillation photons in digital silicon photomultipliers: model and validation.

    PubMed

    van Dam, Herman T; Seifert, Stefan; Schaart, Dennis R

    2012-08-01

    In the design and application of scintillation detectors based on silicon photomultipliers (SiPMs), e.g. in positron emission tomography imaging, it is important to understand and quantify the non-proportionality of the SiPM response due to saturation, crosstalk and dark counts. A new type of SiPM, the so-called digital silicon photomultiplier (dSiPM), has recently been introduced. Here, we develop a model of the probability distribution of the number of fired microcells, i.e. the number of counted scintillation photons, in response to a given amount of energy deposited in a scintillator optically coupled to a dSiPM. Based on physical and functional principles, the model elucidates the statistical behavior of dSiPMs. The model takes into account the photon detection efficiency of the detector; the light yield, excess variance and time profile of the scintillator; and the crosstalk probability, dark count rate, integration time and the number of microcells of the dSiPM. Furthermore, relations for the expectation value and the variance of the number of fired cells are deduced. These relations are applied in the experimental validation of the model using a dSiPM coupled to a LSO:Ce,Ca scintillator. Finally, we propose an accurate method for the correction of energy spectra measured with dSiPM-based scintillation detectors. PMID:22796633

  5. The statistical distribution of the number of counted scintillation photons in digital silicon photomultipliers: model and validation

    NASA Astrophysics Data System (ADS)

    van Dam, Herman T.; Seifert, Stefan; Schaart, Dennis R.

    2012-08-01

    In the design and application of scintillation detectors based on silicon photomultipliers (SiPMs), e.g. in positron emission tomography imaging, it is important to understand and quantify the non-proportionality of the SiPM response due to saturation, crosstalk and dark counts. A new type of SiPM, the so-called digital silicon photomultiplier (dSiPM), has recently been introduced. Here, we develop a model of the probability distribution of the number of fired microcells, i.e. the number of counted scintillation photons, in response to a given amount of energy deposited in a scintillator optically coupled to a dSiPM. Based on physical and functional principles, the model elucidates the statistical behavior of dSiPMs. The model takes into account the photon detection efficiency of the detector; the light yield, excess variance and time profile of the scintillator; and the crosstalk probability, dark count rate, integration time and the number of microcells of the dSiPM. Furthermore, relations for the expectation value and the variance of the number of fired cells are deduced. These relations are applied in the experimental validation of the model using a dSiPM coupled to a LSO:Ce,Ca scintillator. Finally, we propose an accurate method for the correction of energy spectra measured with dSiPM-based scintillation detectors.

  6. Generalized binomial distribution in photon statistics

    E-print Network

    Aleksey V. Ilyin

    2015-05-28

    The photon-number distribution between two parts of a given volume is found for an arbitrary photon statistics. This problem is related to the interaction of a light beam with a macroscopic device, for example a diaphragm, that separates the photon flux into two parts with known probabilities. To solve this problem, a Generalized Binomial Distribution (GBD) is derived that is applicable to an arbitrary photon statistics satisfying probability convolution equations. It is shown that if photons obey Poisson statistics then the GBD is reduced to the ordinary binomial distribution, whereas in the case of Bose-Einstein statistics the GBD is reduced to the Polya distribution. In this case, the photon spatial distribution depends on the phase-space volume occupied by the photons. This result involves a photon bunching effect, or collective behavior of photons that sharply differs from the behavior of classical particles. It is shown that the photon bunching effect looks similar to the quantum interference effect.

  7. Numerical reconstruction of photon-number statistics from photocounting statistics: Regularization of an ill-posed problem

    E-print Network

    V. N. Starkov; A. A. Semenov; H. V. Gomonay

    2009-07-18

    We demonstrate a practical possibility of loss compensation in measured photocounting statistics in the presence of dark counts and background radiation noise. It is shown that satisfactory results are obtained even in the case of low detection efficiency and large experimental errors.

  8. Numerical reconstruction of photon-number statistics from photocounting statistics: Regularization of an ill-posed problem

    SciTech Connect

    Starkov, V. N. [Institute of Physics, National Academy of Sciences of Ukraine, Prospect Nauky 46, UA-03028 Kiev (Ukraine); Semenov, A. A. [Institute of Physics, National Academy of Sciences of Ukraine, Prospect Nauky 46, UA-03028 Kiev (Ukraine); Institute of Physics and Technology, National Technical University of Ukraine 'KPI', Prospect Peremohy 37, UA-03056 Kiev (Ukraine); Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine, Vul. Metrologichna 14-b, UA-03680 Kiev (Ukraine); Gomonay, H. V. [Institute of Physics and Technology, National Technical University of Ukraine 'KPI', Prospect Peremohy 37, UA-03056 Kiev (Ukraine); Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine, Vul. Metrologichna 14-b, UA-03680 Kiev (Ukraine)

    2009-07-15

    We demonstrate a practical possibility of loss compensation in measured photocounting statistics in the presence of dark counts and background radiation noise. It is shown that satisfactory results are obtained even in the case of low detection efficiency and large experimental errors.

  9. Photon-number statistics from resonance fluorescence of a two-level atom near a plasmonic nanoparticle

    NASA Astrophysics Data System (ADS)

    Pastukhov, Vladimir M.; Vladimirova, Yulia V.; Zadkov, Victor N.

    2014-12-01

    The photon-number statistics from resonance fluorescence of a two-level atom near a metal nanosphere driven by a laser field with finite bandwidth is studied theoretically. Our analysis shows that all interesting physics here takes place in a small area around the nanosphere where the near field and the atom-nanosphere coupling essentially affect the radiative properties of the atom. Computer modeling estimates this area roughly as r ?2 a (r is the distance from the center of the nanosphere to the atom), with a being the radius of the nanosphere. At the larger distances, the influence of the nanoparticle vanishes and the atom tends to behave similarly to that in free space. It is shown that the distribution function p (n ,T ) of the emission probability of n photons in a given time interval T in steady-state resonance fluorescence drastically depends on the atom location around the nanosphere for r ?2 a , featuring a characteristic twist in the ridgelike dependence and a convergence time of up to 9 ? s, two orders of magnitude slower than for the atom in free space. At large distances, the distribution converges to a Gaussian one, as for the atom in free space. The typical convergence time scale at large distances r >2 a tends to the convergence time of the atom in free space. There are also two areas symmetrical around the nanosphere in which ? ˜? and the convergence time goes to zero. This behavior is determined by the interplay of the radiative and nonradiative decay rates of the atom due to the coupling with the metal nanosphere and by the near-field intensity. Additional parameters are the normalized laser frequency detuning from the atomic resonance and the bandwidth of the incoming laser field.

  10. Reconstruction of photon statistics using low performance photon counters

    Microsoft Academic Search

    Guido Zambra; Matteo G. A. Paris

    2006-01-01

    The output of a photodetector consists of a current pulse whose charge has\\u000athe statistical distribution of the actual photon numbers convolved with a\\u000aBernoulli distribution. Photodetectors are characterized by a nonunit quantum\\u000aefficiency, i.e. not all the photons lead to a charge, and by a finite\\u000aresolution, i.e. a different number of detected photons leads to a\\u000adiscriminable values

  11. Photon statistics dispersion in excitonic composites

    E-print Network

    G. Ya. Slepyan; S. A. Maksimenko

    2006-05-22

    Linear media are predicted to exist whose relative permiability is an operator in the space of quantum states of light. Such media are characterized by a photon statistics--dependent refractive index. This indicates a new type of optical dispersion -- the photon statistics dispersion. Interaction of quantum light with such media modifies the photon number distribution and, in particular, the degree of coherence of light. An excitonic composite -- a collection of noninteracting quantum dots -- is considered as a realization of the medium with the photon statistics dispersion. Expressions are derived for generalized plane waves in an excitonic composite and input--output relations for a planar layer of the material. Transformation rules for different photon initial states are analyzed. Utilization of the photon statistics dispersion in potential quantum--optical devices is discussed.

  12. Characterization of photon statistics in a single-photon source via variable attenuation

    SciTech Connect

    Zhang Shengli [Key Laboratory of Quantum Information, University of Science and Technology of China (CAS), Hefei 230026 (China); Electronic Technology Institute, Information Engineering University, Zhengzhou, Henan 450004 (China); Zou Xubo; Li Chuanfeng; Guo Guangcan [Key Laboratory of Quantum Information, University of Science and Technology of China (CAS), Hefei 230026 (China); Jin Chenhui [Electronic Technology Institute, Information Engineering University, Zhengzhou, Henan 450004 (China)

    2009-10-15

    We propose a simple but effective scheme for characterizing photon-number statistics of a practical single-photon source. In this scheme, the variable attenuation method which frequently appears in decoy state quantum cryptography is utilized here to enhance the estimation of photon-number statistics. A much stricter bound for vacuum and single-photon proportions is obtained and this result, in turn, is shown to be applicable to the unconditional secure quantum cryptographic communication with single-photon devices.

  13. Photon statistics in the macroscopic realm measured without photon counters

    SciTech Connect

    Andreoni, Alessandra; Bondani, Maria [Dipartimento di Fisica e Matematica, Universita degli Studi dell'Insubria and CNISM, U.d.R. Como, I-22100 Como (Italy); National Laboratory for Ultrafast and Ultraintense Optical Science, CNR-INFM and CNISM, U.d.R. Como, I-22100 Como (Italy)

    2009-07-15

    In a macroscopic realm, in which photons are too many to be counted by any photon-counting detector, photon statistics can be measured by using detectors simply endowed with linear response. We insert one of such detectors in a conventional photon-counting apparatus, which returns a voltage every time the detector responds to light by generating a number of elementary charges via its primary photodetection process. We only assume that, when a single charge is photogenerated, the probability density of the voltages is a distribution that is narrow with respect to its mean value. Under this hypothesis the output voltages can be suitably binned so that their probability distribution is the same as that of the photogenerated charges, that is, of the detected photons.

  14. Statistical bias in material decomposition in low photon statistics region

    NASA Astrophysics Data System (ADS)

    Rajbhandary, Paurakh L.; Pelc, Norbert J.

    2015-03-01

    We show that in material decomposition, statistical bias exists in the low photon regime due to non-linearity including but not limited to the log operation and polychromatic measurements. As new scan methods divide the total number of photons into an increasing number of measurements (e.g., energy bins, projection paths) and as developers seek to reduce radiation dose, the number of photons per measurement will decrease and estimators should be robust against bias at low photon counts. We study bias as a function of total flux and spectral spread, which provides insight when parameters like material thicknesses, number of energy bins, and number of projection views change. We find that the bias increases with lower photon counts, wide spectrum, with more number of energy bins and more projection views. Our simulation, with ideal photon counting detectors, show biases up to 2.4 % in basis material images. We propose a bias correction method in projection space that uses a multi dimensional look up table. With the correction, the relative bias in CT images is within 0.5 ± 0.17%.

  15. Reconstruction of photon-number distribution using low-performance photon counters

    Microsoft Academic Search

    Guido Zambra; Matteo G. A. Paris

    2006-01-01

    The output of a photodetector consists of a current pulse whose charge has the statistical distribution of the actual photon numbers convolved with a Bernoulli distribution. Photodetectors are characterized by a nonunit quantum efficiency, i.e., not all the photons lead to a charge, and by a finite resolution, i.e., a different number of detected photons leads to a discriminable values

  16. Photon statistics without counting photons Andrea R. Rossi,* Stefano Olivares,

    E-print Network

    Paris, Matteo G. A.

    Photon statistics without counting photons Andrea R. Rossi,* Stefano Olivares, and Matteo G. A of an indirect method used to obtain the photon distribution of a single-mode field using only on/off avalanche photons. In this scheme, repeated preparations of the signal are revealed through avalanche photodetectors

  17. Relativistic statistical thermodynamics of dense photon gas

    SciTech Connect

    Tsintsadze, Levan N.; Kishimoto, Yasuaki; Callebaut, Dirk K.; Tsintsadze, Nodar L. [Department of Fundamental Energy, Graduate School of Energy Science, Kyoto University (Japan); Physics Department, University of Antwerp, Antwerpen (Belgium); Department of Plasma Physics, Tbilisi State University, Tbilisi (Georgia)

    2007-07-15

    We discuss some aspects of interactions of high-frequency electromagnetic waves with plasmas, assuming that the intensity of radiation is sufficiently large, so that the photon-photon interaction is more likely than the photon-plasma particle interaction. In the stationary limit, solving the kinetic equation of the photon gas, we derive a distribution function. With this distribution function at hand, we investigate the adiabatic photon self-capture and obtain the number density of the trapped photons. We employ the distribution function to calculate the thermodynamic quantities for the photon gas. Having expressions of the entropy and the pressure of the photon gas, we define the heat capacities and exhibit the existence of the ratio of the specific heats {gamma}, which equals 7/6 for nonrelativistic temperatures. In addition, we disclose the magnitude of the mean square fluctuation of the number of photons. Finally, we discuss the uniform expansion of the photon gas.

  18. Theory of photon coincidence statistics in photon-correlated beams

    NASA Astrophysics Data System (ADS)

    Hayat, Majeed M.; Torres, Sergio N.; Pedrotti, Leno M.

    1999-10-01

    The statistics of photon coincidence counting in photon-correlated beams is thoroughly investigated considering the effect of the finite coincidence resolving time. The correlated beams are assumed to be generated using parametric downconversion, and the photon streams in the correlated beams are modeled by two partially correlated Poisson point processes. An exact expression for the mean rate of coincidence registration is developed using techniques from renewal theory. It is shown that the use of the traditional approximate rate, in certain situations, leads to the overestimation of the actual rate. The error between the exact and approximate coincidence rates increases as the coincidence-noise parameter, defined as the mean number of uncorrelated photons detected per coincidence resolving time, increases. The use of the exact statistics of the coincidence becomes crucial when the background noise is high or in cases when high precision measurement of coincidence is required. Such cases arise whenever the coincidence-noise parameter is even slightly in excess of zero. It is also shown that the probability distribution function of the time between consecutive coincidence registration can be well approximated by an exponential distribution function. The well-known and experimentally verified Poissonian model of the coincidence registration process is therefore theoretically justified. The theory is applied to an on-off keying communication system proposed by Mandel which has been shown to perform well in extremely noisy conditions. It is shown that the bit-error rate (BER) predicted by the approximate coincidence-rate theory can be significantly lower than the actual BER obtained using the exact theory.

  19. Probing higher order correlations of the photon field with photon number resolving avalanche photodiodes

    E-print Network

    Dynes, J F; Sharpe, A W; Thomas, O; Shields, A J; 10.1364/OE.19.013268

    2011-01-01

    We demonstrate the use of two high speed avalanche photodiodes in exploring higher order photon correlations. By employing the photon number resolving capability of the photodiodes the response to higher order photon coincidences can be measured. As an example we show experimentally the sensitivity to higher order correlations for three types of photon sources with distinct photon statistics. This higher order correlation technique could be used as a low cost and compact tool for quantifying the degree of correlation of photon sources employed in quantum information science.

  20. Probing higher order correlations of the photon field with photon number resolving avalanche photodiodes

    E-print Network

    J. F. Dynes; Z. L. Yuan; A. W. Sharpe; O. Thomas; A. J. Shields

    2011-07-15

    We demonstrate the use of two high speed avalanche photodiodes in exploring higher order photon correlations. By employing the photon number resolving capability of the photodiodes the response to higher order photon coincidences can be measured. As an example we show experimentally the sensitivity to higher order correlations for three types of photon sources with distinct photon statistics. This higher order correlation technique could be used as a low cost and compact tool for quantifying the degree of correlation of photon sources employed in quantum information science.

  1. Quantum random-number generator based on a photon-number-resolving detector

    SciTech Connect

    Ren Min; Wu, E; Liang Yan; Jian Yi; Wu Guang; Zeng Heping [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China)

    2011-02-15

    We demonstrated a high-efficiency quantum random number generator which takes inherent advantage of the photon number distribution randomness of a coherent light source. This scheme was realized by comparing the photon flux of consecutive pulses with a photon number resolving detector. The random bit generation rate could reach 2.4 MHz with a system clock of 6.0 MHz, corresponding to a random bit generation efficiency as high as 40%. The random number files passed all the stringent statistical tests.

  2. Observing fermionic statistics with photons in arbitrary processes

    PubMed Central

    Matthews, Jonathan C. F.; Poulios, Konstantinos; Meinecke, Jasmin D. A.; Politi, Alberto; Peruzzo, Alberto; Ismail, Nur; Wörhoff, Kerstin; Thompson, Mark G.; O'Brien, Jeremy L.

    2013-01-01

    Quantum mechanics defines two classes of particles-bosons and fermions-whose exchange statistics fundamentally dictate quantum dynamics. Here we develop a scheme that uses entanglement to directly observe the correlated detection statistics of any number of fermions in any physical process. This approach relies on sending each of the entangled particles through identical copies of the process and by controlling a single phase parameter in the entangled state, the correlated detection statistics can be continuously tuned between bosonic and fermionic statistics. We implement this scheme via two entangled photons shared across the polarisation modes of a single photonic chip to directly mimic the fermion, boson and intermediate behaviour of two-particles undergoing a continuous time quantum walk. The ability to simulate fermions with photons is likely to have applications for verifying boson scattering and for observing particle correlations in analogue simulation using any physical platform that can prepare the entangled state prescribed here. PMID:23531788

  3. Reconstruction of photon-number distribution using low-performance photon counters Guido Zambra1,2

    E-print Network

    Paris, Matteo G. A.

    in the above fields, photon detectors that can operate as photon counters 3,4 for any state of radiation the statistical distribution of the actual photon numbers convolved with a Bernoulli distribution. Photodetectors and real data, among the performances of detectors with different upper limits of counting capability

  4. Density matrix reconstruction from displaced photon number distributions

    E-print Network

    Jukka Kiukas; Juha-Pekka Pellonpää; Jussi Schultz

    2009-10-19

    We consider state reconstruction from the measurement statistics of phase space observables generated by photon number states. The results are obtained by inverting certain infinite matrices. In particular, we obtain reconstruction formulas, each of which involves only a single phase space observable.

  5. Photon number distributions from a diode laser.

    PubMed

    Roumpos, Georgios; Cundiff, Steven T

    2013-01-15

    We use balanced homodyne detection to characterize light from a diode laser as it crosses the threshold. We measure the single-time second-order correlation function g(2), and also extract the photon number distribution. Just above the laser threshold, we find that the measured g(2) exceeds the prediction of the semiclassical single-mode laser model. From the reconstructed photon number distributions, we conclude that this excess is due to emission from nonlasing modes. For higher pumping current, the light noise increases due to a different mechanism, possibly mode competition or mode partition noise. PMID:23454941

  6. Calibration of single-photon detectors using quantum statistics

    SciTech Connect

    Mogilevtsev, D. [Institute of Physics, Belarus National Academy of Sciences, F.Skarina Ave. 68, Minsk 220072 (Belarus) and Instituto de Fisica, UNICAMP, CP 6165, Campinas-SP, 13083-970 (Brazil)

    2010-08-15

    I show that calibration of the single-photon detector can be performed without knowledge of the signal parameters. Only partial information about the state statistics is sufficient for that. If one knows that the state is the squeezed one or the squeezed one mixed with the incoherent radiation, one can infer both the parameters of the state and the efficiency of the detector. For that one needs only to measure on/off statistics of detector clicks for the number of known absorbers placed before the detector. Thus, I suggest a scheme that performs a tomography of the signal and the measuring apparatus simultaneously.

  7. Photon--added squeezed thermal states: statistical properties and its decoherence in a photon-loss channel

    E-print Network

    Xue-xiang Xu; Li-yun Hu; Hong-yi Fan

    2009-08-10

    Using the normally ordered Gaussian form of displaced-squeezed thermal field characteristic of average photon number n, we introduce the photon-added squeezed thermo state (PASTS) and investigate its statistical properties, such as Mandel's Q-parameter, number distribution (as a Legendre polynomial), the Wigner function. We then study its decoherence in a photon-loss channel in term of the negativity of WF by deriving the analytical expression of WF for PASTS. It is found that the WF with single photon-added is always partial negative for the arbitrary values of n and the squeezing parameter r.

  8. Interaction of Fixed Number of Photons with Retinal Rod Cells

    NASA Astrophysics Data System (ADS)

    Phan, Nam Mai; Cheng, Mei Fun; Bessarab, Dmitri A.; Krivitsky, Leonid A.

    2014-05-01

    New tools and approaches of quantum optics offer a unique opportunity to generate light pulses carrying a precise number of photons. Accurate control over the light pulses helps to improve the characterization of photoinduced processes. Here, we study interaction of a specialized light source which provides flashes containing just one photon, with retinal rod cells of Xenopus laevis toads. We provide unambiguous proof of the single-photon sensitivity of rod cells without relying on the statistical modeling. We determine their quantum efficiencies without the use of any precalibrated detectors and obtain the value of (29±4.7)%. Our approach provides the path for future studies and applications of quantum properties of light in phototransduction, vision, and photosynthesis.

  9. Nonlinearity sensing via photon-statistics excitation spectroscopy

    SciTech Connect

    Assmann, Marc; Bayer, Manfred [Experimentelle Physik 2, Technische Universitaet Dortmund, D-44221 Dortmund (Germany)

    2011-11-15

    We propose photon-statistics excitation spectroscopy as an adequate tool to describe the optical response of a nonlinear system. To this end we suggest to use optical excitation with varying photon statistics as another spectroscopic degree of freedom to gather information about the system in question. The responses of several simple model systems to excitation beams with different photon statistics are discussed. Possible spectroscopic applications in terms of identifying lasing operation are pointed out.

  10. Linking numbers, spin, and statistics of solitons

    NASA Technical Reports Server (NTRS)

    Wilczek, F.; Zee, A.

    1983-01-01

    The spin and statistics of solitons in the (2 + 1)- and (3 + 1)-dimensional nonlinear sigma models is considered. For the (2 + 1)-dimensional case, there is the possibility of fractional spin and exotic statistics; for 3 + 1 dimensions, the usual spin-statistics relation is demonstrated. The linking-number interpretation of the Hopf invariant and the use of suspension considerably simplify the analysis.

  11. Induced photon statistics in three-level lasers

    E-print Network

    T. Golubeva; Yu. Golubev

    2006-04-12

    The statistical properties of three-level lasing are investigated theoretically. It is assumed that the three-level medium is coherently excited by another laser with an arbitrary photon statistics. It is proved that, under the specific conditions, the photon statistics of the three-level laser duplicate the photon statistics of the exciting laser. We call this phenomenon an induced photon statistics. We suggest to use this to analyze the statistical properties of a laser involved into a feedback process. Applying this laser for the coherent pump of a three-level laser, we can follow its photon statistics by means of direct following the three-level generation. In accordance with [H. M. Wiseman and G. J. Milburn, Phys. Rev. A, 49, 1350-1366 (1994)], we conclude that the feedback in itself is unable to generate the non-classical manifestation in the laser field.

  12. Noise due to photon counting statistics in computed x-ray tomography

    Microsoft Academic Search

    D. A. Chesler; S. J. Riederer; N. J. Pelc

    1977-01-01

    A general expression is derived for the noise due to photon counting statistics in computed x-ray tomography. The variance is inversely proportional to the cube of the resolution distance. For scanners using a water box, the noise in the reconstructed image depends inversely on the number of detected primary photons, summed over all angles, that have passed through a resolution

  13. Statistical Applets: Law of Large Numbers

    NSDL National Science Digital Library

    Duckworth, William

    Created by authors Duckworth, McCabe, Moore and Sclove for W.H. Freeman and Co., this applet is designed to help students understand the Law of Large Numbers by simulating rolling dice. The applet graphs the mean of the sum of the rolls for user specified conditions. This applet accompanies "Practice of Business Statistics;" however, it can be used without this text. Even though brief, this is still a nice interactive resource for an introductory statistics course.

  14. Significant Figures of Numbers in Statistical Tables

    Microsoft Academic Search

    S. A. Goudsmit; W. H. Furry

    1944-01-01

    IT is a well-known fact that most numbers in statistical tables start with a small digit. For example, in population tables almost one third of the entries begin with the digit 1. The same holds true for most tables of the type occurring in the World's Almanac.

  15. Photon statistics of atomic fluorescence after {pi}-pulse excitation

    SciTech Connect

    Yoshimi, Kazuyoshi [College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Chiba 272-0827 (Japan); Koshino, Kazuki [College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Chiba 272-0827 (Japan); PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan)

    2010-09-15

    The photon statistics of atomic fluorescence after {pi}-pulse excitation is investigated in a system in which the input and output ports are connected to an atom. Since spontaneous decay during input pulse excitation occurs, the output pulse generally contains a multiphoton component with a certain probability. We quantitatively evaluate the probability of the output pulse containing multiple photons and determine the conditions for ideal single-photon generation.

  16. Joint multipartite photon statistics by on/off detection

    E-print Network

    G. Brida; M. Genovese; M. G. A. Paris; F. Piacentini

    2006-06-23

    We demonstrate a method to reconstruct the joint photon statistics of two or more modes of radiation using on/off photodetection performed at different quantum efficiencies. The two-mode case is discussed in details and experimental results are presented for the bipartite states obtained after a beam-splitter fed by a single photon state or a thermal state.

  17. Photon statistics of coherent harmonic radiation of a linac free electron laser

    NASA Astrophysics Data System (ADS)

    Chen, Teng

    The subject of statistical fluctuations in a free electron laser (FEL) is both fundamental and significant to the understanding of FEL radiation. This dissertation deals with two relevant issues in this regard: the photon statistics of the visible coherent spontaneous harmonic radiation (CSHR); and the examination of the electron shot-noise interpretation of the observed statistical fluctuations. In this dissertation, we present the first experimental demonstration of the photon statistics of the FEL CSHR by the means of a photon counting experiment. We constructed the photon counting experiment for the 7th coherent spontaneous harmonic radiation on the Mark III FEL. The statistical property of the radiation is obtained by counting the number of photons emitted at an equivalent point in time for each member of an ensemble. The well- defined ensemble of radiation systems required for the experiment is achieved by suppressing the classical noise mainly associated with electron beam instabilities. The classical fluctuations are effectively suppressed through both the use of a trigger and the efforts to stabilizing the FEL gain and the electron beam. As a result, we measured the photon number fluctuations for the 7th CSHR generated by a series of identically prepared electron pulses. The experimental observation indicates that the 7th coherent spontaneous harmonic radiation displayed sub-Poisson photon statistics. On the other hand, numerical analysis is presented to investigate the validity of the shot-noise hypothesis. The shot-noise model has been relied on to explain the optical fluctuations observed in the FEL in the past. It attributes all observed statistical fluctuations to the shot-noise distribution in the density of the electron current. It will be shown that the electron shot-noise model is inadequate to explain the statistical fluctuations observed in the optical field.

  18. Superconducting nanowire photon number resolving detector at telecom wavelength

    E-print Network

    Divochiy, Aleksander; Bitauld, David; Gaggero, Alessandro; Leoni, Roberto; Mattioli, Francesco; Korneev, Alexander; Seleznev, Vitaliy; Kaurova, Nataliya; Minaeva, Olga; Goltsman, Gregory; Lagoudakis, Konstantinos G; Benkhaoul, Moushab; Levy, Francis; Fiore, Andrea

    2007-01-01

    The optical-to-electrical conversion, which is the basis of optical detectors, can be linear or nonlinear. When high sensitivities are needed single-photon detectors (SPDs) are used, which operate in a strongly nonlinear mode, their response being independent of the photon number. Nevertheless, photon-number resolving (PNR) detectors are needed, particularly in quantum optics, where n-photon states are routinely produced. In quantum communication, the PNR functionality is key to many protocols for establishing, swapping and measuring entanglement, and can be used to detect photon-number-splitting attacks. A linear detector with single-photon sensitivity can also be used for measuring a temporal waveform at extremely low light levels, e.g. in long-distance optical communications, fluorescence spectroscopy, optical time-domain reflectometry. We demonstrate here a PNR detector based on parallel superconducting nanowires and capable of counting up to 4 photons at telecommunication wavelengths, with ultralow dark ...

  19. Exploration of photon-number entangled states using weak nonlinearities

    E-print Network

    Yingqiu He; Dong Ding; Fengli Yan; Ting Gao

    2015-04-03

    A method for exploring photon-number entangled states with weak nonlinearities is described. We show that it is possible to create and detect such entanglement at various scales, ranging from microscopic to macroscopic systems. In the present architecture, we suggest that the maximal phase shift induced in the process of interaction between photons is proportional to photon numbers. Also, in the absence of decoherence we analyze maximum error probability and show its feasibility with current technology.

  20. Quantum dot single-photon switches of resonant tunneling current for discriminating-photon-number detection

    PubMed Central

    Weng, Qianchun; An, Zhenghua; Zhang, Bo; Chen, Pingping; Chen, Xiaoshuang; Zhu, Ziqiang; Lu, Wei

    2015-01-01

    Low-noise single-photon detectors that can resolve photon numbers are used to monitor the operation of quantum gates in linear-optical quantum computation. Exactly 0, 1 or 2 photons registered in a detector should be distinguished especially in long-distance quantum communication and quantum computation. Here we demonstrate a photon-number-resolving detector based on quantum dot coupled resonant tunneling diodes (QD-cRTD). Individual quantum-dots (QDs) coupled closely with adjacent quantum well (QW) of resonant tunneling diode operate as photon-gated switches- which turn on (off) the RTD tunneling current when they trap photon-generated holes (recombine with injected electrons). Proposed electron-injecting operation fills electrons into coupled QDs which turn “photon-switches” to “OFF” state and make the detector ready for multiple-photons detection. With proper decision regions defined, 1-photon and 2-photon states are resolved in 4.2?K with excellent propabilities of accuracy of 90% and 98% respectively. Further, by identifying step-like photon responses, the photon-number-resolving capability is sustained to 77?K, making the detector a promising candidate for advanced quantum information applications where photon-number-states should be accurately distinguished. PMID:25797442

  1. Quantum dot single-photon switches of resonant tunneling current for discriminating-photon-number detection.

    PubMed

    Weng, Qianchun; An, Zhenghua; Zhang, Bo; Chen, Pingping; Chen, Xiaoshuang; Zhu, Ziqiang; Lu, Wei

    2015-01-01

    Low-noise single-photon detectors that can resolve photon numbers are used to monitor the operation of quantum gates in linear-optical quantum computation. Exactly 0, 1 or 2 photons registered in a detector should be distinguished especially in long-distance quantum communication and quantum computation. Here we demonstrate a photon-number-resolving detector based on quantum dot coupled resonant tunneling diodes (QD-cRTD). Individual quantum-dots (QDs) coupled closely with adjacent quantum well (QW) of resonant tunneling diode operate as photon-gated switches- which turn on (off) the RTD tunneling current when they trap photon-generated holes (recombine with injected electrons). Proposed electron-injecting operation fills electrons into coupled QDs which turn "photon-switches" to "OFF" state and make the detector ready for multiple-photons detection. With proper decision regions defined, 1-photon and 2-photon states are resolved in 4.2 K with excellent propabilities of accuracy of 90% and 98% respectively. Further, by identifying step-like photon responses, the photon-number-resolving capability is sustained to 77 K, making the detector a promising candidate for advanced quantum information applications where photon-number-states should be accurately distinguished. PMID:25797442

  2. Towards a Metric to Estimate Atomic Number from Backscattered Photons

    SciTech Connect

    Walston, S; Dietrich, D; Wurtz, R

    2009-08-17

    An ability to determine the atomic number of a material in a cargo container would be helpful in interdicting smuggled nuclear materials. This paper examines two processes by which high energy photons interact with matter; Compton scattering and pair production. The ratio of the number of photons which originate from the annihilation of positrons resulting from pair production and the number of photons coming from Compton scattering gives a good indication of atomic number. At large angles relative to an incident beam - i.e. backscattered, there is good separation in energy between Compton scattered photons and photons from positron annihilations. This ratio can then be cleanly determined in order to estimate atomic number.

  3. Photon statistics of a two-mode squeezed vacuum

    NASA Technical Reports Server (NTRS)

    Schrade, Guenter; Akulin, V. M.; Schleich, W. P.; Manko, Vladimir I.

    1994-01-01

    We investigate the general case of the photon distribution of a two-mode squeezed vacuum and show that the distribution of photons among the two modes depends on four parameters: two squeezing parameters, the relative phase between the two oscillators and their spatial orientation. The distribution of the total number of photons depends only on the two squeezing parameters. We derive analytical expressions and present pictures for both distributions.

  4. Role of photon statistics in energy-efficient optical computers

    Microsoft Academic Search

    Joseph Shamir; H. J. Caulfield; Devon G. Crowe

    1991-01-01

    One of the limiting factors in the operation of highly energy-efficient optical computers is the fluctuation in the rate of photon detection events. Obviously, the smaller the number of photon detection events required for a measurement, the higher the energy efficiency of the systems. Squeezed light technology, which appeared to be a possible way to mitigate this fluctuation, is shown

  5. Photon statistics of acousto-optic modulation

    Microsoft Academic Search

    Mateo Restrepo; Angela M. Guzman; William T. Rhodes; Jean-Pierre Goedgebuer

    2003-01-01

    We analyze the quantum statistical properties of light scattered by an acousto-optic modulator. From the perspective of quantum mechanics, the acousto-optic effect arises from a nonlinear interaction between three bosonic fields: the laser light, the Brillouin-scattered light, and an acoustic wave. The Hamiltonian coincides with that of sum-frequency generation, where the sum-frequency mode is known to exhibit sub-Poissonian statistics. We

  6. Photon Statistics of Single Carbon Nanotubes at Room Temperature

    NASA Astrophysics Data System (ADS)

    Ma, Xuedan; Duque, Juan; Crochet, Jared; Mangum, Benjamin; Doorn, Stephen; Htoon, Han

    2013-03-01

    Different from zero-dimensional systems such as atoms, molecules, and quantum dots, semiconducting single-walled carbon nanotubes (SWNTs) are ideal one-dimensional systems that allow free diffusion of excitons along their length. Studies have also shown that multiple excitons exist within the diffusion length can annihilate via Auger process. Interplay of Auger process and exciton diffusion therefore could have interesting effects on photon emission statistics of SWNTs. Current existing studies on photon emission statistics were conducted at low temperature where excitons were localized to quantum-dot-like states. To this end we conduct room temperature 2nd order photon correlation spectroscopy studies on high quality SWNTs capable of emitting continuous photoluminescence along their length which could extend up to several micrometers. We observed the degree of photon-bunching lower than 0.5 at the lowest pumping powers. We will also present a correlation between the diffusion length and the degree of photon-bunching. Our study could have implications toward utilizing SWNTs as room temperature single photon sources.

  7. Calibration of single-photon detectors using quantum statistics

    Microsoft Academic Search

    Mogilevtsev

    2010-01-01

    I show that calibration of the single-photon detector can be performed without knowledge of the signal parameters. Only partial information about the state statistics is sufficient for that. If one knows that the state is the squeezed one or the squeezed one mixed with the incoherent radiation, one can infer both the parameters of the state and the efficiency of

  8. The Role of Photon Statistics in Laser ‘Sparks’

    Microsoft Academic Search

    J. W. GARDNER

    1966-01-01

    It is known that the production of ‘sparks’ in gases by focused laser beams must involve a triggering process different from the acceleration of random free electrons responsible for conventional sparks. Photo-ionization of the gases in question requires the ‘simultaneous’ absorption of several photons by a gas atom, so that any theory invoking this effect must take account of statistical

  9. Ultrabroadband direct detection of nonclassical photon statistics at telecom wavelength

    NASA Astrophysics Data System (ADS)

    Wakui, Kentaro; Eto, Yujiro; Benichi, Hugo; Izumi, Shuro; Yanagida, Tetsufumi; Ema, Kazuhiro; Numata, Takayuki; Fukuda, Daiji; Takeoka, Masahiro; Sasaki, Masahide

    2014-04-01

    Broadband light sources play essential roles in diverse fields, such as high-capacity optical communications, optical coherence tomography, optical spectroscopy, and spectrograph calibration. Although a nonclassical state from spontaneous parametric down-conversion may serve as a quantum counterpart, its detection and characterization have been a challenging task. Here we demonstrate the direct detection of photon numbers of an ultrabroadband (110 nm FWHM) squeezed state in the telecom band centred at 1535 nm wavelength, using a superconducting transition-edge sensor. The observed photon-number distributions violate Klyshko's criterion for the nonclassicality. From the observed photon-number distribution, we evaluate the second- and third-order correlation functions, and characterize a multimode structure, which implies that several tens of orthonormal modes of squeezing exist in the single optical pulse. Our results and techniques open up a new possibility to generate and characterize frequency-multiplexed nonclassical light sources for quantum info-communications technology.

  10. Ultrabroadband direct detection of nonclassical photon statistics at telecom wavelength.

    PubMed

    Wakui, Kentaro; Eto, Yujiro; Benichi, Hugo; Izumi, Shuro; Yanagida, Tetsufumi; Ema, Kazuhiro; Numata, Takayuki; Fukuda, Daiji; Takeoka, Masahiro; Sasaki, Masahide

    2014-01-01

    Broadband light sources play essential roles in diverse fields, such as high-capacity optical communications, optical coherence tomography, optical spectroscopy, and spectrograph calibration. Although a nonclassical state from spontaneous parametric down-conversion may serve as a quantum counterpart, its detection and characterization have been a challenging task. Here we demonstrate the direct detection of photon numbers of an ultrabroadband (110 nm FWHM) squeezed state in the telecom band centred at 1535 nm wavelength, using a superconducting transition-edge sensor. The observed photon-number distributions violate Klyshko's criterion for the nonclassicality. From the observed photon-number distribution, we evaluate the second- and third-order correlation functions, and characterize a multimode structure, which implies that several tens of orthonormal modes of squeezing exist in the single optical pulse. Our results and techniques open up a new possibility to generate and characterize frequency-multiplexed nonclassical light sources for quantum info-communications technology. PMID:24694515

  11. Ultrabroadband direct detection of nonclassical photon statistics at telecom wavelength

    PubMed Central

    Wakui, Kentaro; Eto, Yujiro; Benichi, Hugo; Izumi, Shuro; Yanagida, Tetsufumi; Ema, Kazuhiro; Numata, Takayuki; Fukuda, Daiji; Takeoka, Masahiro; Sasaki, Masahide

    2014-01-01

    Broadband light sources play essential roles in diverse fields, such as high-capacity optical communications, optical coherence tomography, optical spectroscopy, and spectrograph calibration. Although a nonclassical state from spontaneous parametric down-conversion may serve as a quantum counterpart, its detection and characterization have been a challenging task. Here we demonstrate the direct detection of photon numbers of an ultrabroadband (110?nm FWHM) squeezed state in the telecom band centred at 1535?nm wavelength, using a superconducting transition-edge sensor. The observed photon-number distributions violate Klyshko's criterion for the nonclassicality. From the observed photon-number distribution, we evaluate the second- and third-order correlation functions, and characterize a multimode structure, which implies that several tens of orthonormal modes of squeezing exist in the single optical pulse. Our results and techniques open up a new possibility to generate and characterize frequency-multiplexed nonclassical light sources for quantum info-communications technology. PMID:24694515

  12. High quantum-efficiency photon-number-resolving detector for photonic on-chip information processing

    E-print Network

    Calkins, Brice; Lita, Adriana E; Metcalf, Benjamin J; Kolthammer, W Steven; Linares, Antia Lamas; Spring, Justin B; Humphreys, Peter C; Mirin, Richard P; Gates, James C; Smith, Peter G R; Walmsley, Ian A; Gerrits, Thomas; Nam, Sae Woo

    2013-01-01

    The integrated optical circuit is a promising architecture for the realization of complex quantum optical states and information networks. One element that is required for many of these applications is a high-efficiency photon detector capable of photon-number discrimination. We present an integrated photonic system in the telecom band at 1550 nm based on UV-written silica-on-silicon waveguides and modified transition-edge sensors capable of number resolution and over 40% efficiency. Exploiting the mode transmission failure of these devices, we multiplex three detectors in series to demonstrate a combined 79% +/- 2% detection efficiency with a single pass, and 88% +/- 3% at the operating wavelength of an on-chip terminal reflection grating. Furthermore, our optical measurements clearly demonstrate no significant unexplained loss in this system due to scattering or reflections. This waveguide and detector design therefore allows the placement of number-resolving single-photon detectors of predictable efficienc...

  13. Stochastic quantum trajectories in a QND measurement of photon number

    SciTech Connect

    Bukach, A. A., E-mail: a.bukach@dragon.bas-net.by; Kilin, S. Ya. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)

    2007-04-15

    An analysis is presented of the time evolution of an optical field during a quantum nondemolition measurement of photon number using the cross-Kerr interaction between the signal and probe fields. It is shown that the signal field state collapses into a Fock state only asymptotically (in the infinite time limit), remaining in a superposition of two Fock states (Fock-state qubit) throughout most of the measurement period. Estimates are obtained both for the time required to measure photon number to the desired accuracy and for the Fock-state qubit lifetime.

  14. Elementary Business Statistics Unique Number 04595, 04600

    E-print Network

    Ghosh, Joydeep

    _alaubaidy@utexas.edu Shannon Provost Email: smprovost@gmail.com COURSE MATERIALS MyStatLab at https://pearsonmylabandmastering.com/students/register/. Enter the Course ID greenberg66013 to register. Registration requires an Access Code the publisher at http://www.mypearsonstore.com/bookstore/business-statistics-student- value

  15. STATISTICS AND MODELING Unique Number: 04395

    E-print Network

    Ghosh, Joydeep

    making areas of business ­ accounting, finance, economics, marketing, and operations management. Emphasis linear and multiple regression, time series analysis and forecasting. Prerequisites: Management Information Systems 301 or 310; Mathematics 408D, 408L, or 408M; Statistics 309 or 309H; and credit

  16. Quantum random number generator based on the photon number decision of weak laser pulses

    E-print Network

    Wei Wei; J. W. Zhang; Tian Liu; Hong Guo

    2008-11-07

    We propose an approach to realize a quantum random number generator (QRNG) based on the photon number decision of weak laser pulses. This type of QRNG can generate true random numbers at a high speed and can be adjusted to zero bias conveniently, thus is suitable for the applications in quantum cryptography.

  17. Quantum random number generator based on the photon number decision of weak laser pulses

    E-print Network

    Wei, Wei; Liu, Tian; Guo, Hong

    2008-01-01

    We propose a new approach to realize a quantum random number generator (QRNG) based on the photon number decision of weak laser pulses. This new type of QRNG can generate true random numbers at a high speed and can be set to zero bias conveniently, thus is suitable for the applications in quantum cryptography.

  18. LETTER TO THE EDITOR: Photon number variance in isolated cavities

    Microsoft Academic Search

    Fabrice Philippe; Jacques Arnaud

    2001-01-01

    We consider a strictly isolated single-mode optical cavity resonating at angular frequency, omega, containing atoms whose one-electron level energies are supposed to be &plank;omega, 2&plank;omega...B&plank;omega, and m photons. If the atoms are initially in their highest energy state and m = 0, we find that at equilibrium: variance(m)\\/mean(m) = (B + 1)\\/6, indicating that the internal field statistics is sub-Poissonian

  19. Creating and Detecting Micro-Macro Photon-Number Entanglement by Amplifying and Deamplifying a Single-Photon Entangled State

    NASA Astrophysics Data System (ADS)

    Ghobadi, Roohollah; Lvovsky, Alexander; Simon, Christoph

    2013-04-01

    We propose a scheme for the observation of micro-macro entanglement in photon number based on amplifying and deamplifying a single-photon entangled state in combination with homodyne quantum state tomography. The created micro-macro entangled state, which exists between the amplification and deamplification steps, is a superposition of two components with mean photon numbers that differ by approximately a factor of three. We show that for reasonable values of photon loss it should be possible to detect micro-macro photon-number entanglement where the macrosystem has a mean number of one hundred photons or more.

  20. DECOHERENCE OF GAUSSIAN AND NONGAUSSIAN PHOTON-NUMBER ENTANGLED STATES

    E-print Network

    Paris, Matteo G. A.

    states (PNES) and study the degradation of their entanglement in a noisy channel, using di case of entangled resource, namely Photon-Number Entangled States (PNES), a class of two-mode CV entan the degradation of nonGaussian PNES' entanglement. Consequently, we had to resort to additional tools, including

  1. Sum-frequency generation from photon number squeezed light

    NASA Technical Reports Server (NTRS)

    Wu, Ling-An; Du, Cong-Shi; Wu, Mei-Juan; Li, Shi-Qun

    1994-01-01

    We investigate the quantum fluctuations of the fields produced in sum-frequency (SF) generation from light initially in the photon number squeezed state. It is found that, to the fourth power term, the output SF light is sub-Poissonian whereas the quantum fluctuations of the input beams increase. Quantum anticorrelation also exists in SF generation.

  2. Hanbury BrownTwiss Correlations to Probe the Population Statistics of GHz Photons Emitted by Conductors

    E-print Network

    Plaçais, Bernard

    of GHz photons in quantum circuits, using Hanbury Brown and Twiss correlations. The super and the fourth moment of the electron full counting statistics [14]. But how to measure reliably the photonHanbury Brown­Twiss Correlations to Probe the Population Statistics of GHz Photons Emitted

  3. Sigma-Boundary Statistics by Length and Number

    Microsoft Academic Search

    Valerie Randle

    2002-01-01

    This paper presents a rationale for comparative use of length fraction and number fraction statistics in grain boundary analysis from orientation maps generated by electron back-scatter diffraction (EBSD). The length and number fraction statistics for S3n coincidence site lattice (CSL) boundaries were measured and compared. The length fraction of S3 boundaries was 0.48 whereas the number fraction was significantly less,

  4. Nonclassicality characterization in photon statistics based on binary-response single-photon detection

    NASA Astrophysics Data System (ADS)

    Guo, Yanqiang; Yang, Rongcan; Li, Gang; Zhang, Pengfei; Zhang, Yuchi; Wang, Junmin; Zhang, Tiancai

    2011-10-01

    By employing multiple conventional single-photon counting modules (SPCMs), which are binary-response detectors, instead of photon number resolving detectors, the nonclassicality criteria are investigated for various quantum states. The bounds of the criteria are derived from a system based on three or four SPCMs. The overall efficiency and background are both taken into account. The results of experiments with thermal and coherent light agree with the theoretical analysis. Compared with photon number resolving detectors, the use of a Hanbury Brown-Twiss-like scheme with multiple SPCMs is even better for revealing the nonclassicality of the fields, and the efficiency requirements are not so stringent. Some proposals are presented which can improve the detection performance with binary-response SPCMs for different quantum states.

  5. Experimental Observation of Large Chern numbers in Photonic Crystals

    E-print Network

    Skirlo, Scott A; Igarashi, Yuichi; Joannopoulos, John; Soljacic, Marin

    2015-01-01

    Despite great interest in the quantum anomalous Hall phase and its analogs, all experimental studies in electronic and bosonic systems have been limited to a Chern number of one. Here, we perform microwave transmission measurements in the bulk and at the edge of ferrimagnetic photonic crystals. Bandgaps with large Chern numbers of 2, 3 and 4 are clearly present in the experimental results which show excellent agreement with theory. These large Chern number bandgaps support multimode one-way edge waveguides and can be used for the construction of topological power splitters and combiners.

  6. High quantum-efficiency photon-number-resolving detector for photonic on-chip information processing.

    PubMed

    Calkins, Brice; Mennea, Paolo L; Lita, Adriana E; Metcalf, Benjamin J; Kolthammer, W Steven; Lamas-Linares, Antia; Spring, Justin B; Humphreys, Peter C; Mirin, Richard P; Gates, James C; Smith, Peter G R; Walmsley, Ian A; Gerrits, Thomas; Nam, Sae Woo

    2013-09-23

    The integrated optical circuit is a promising architecture for the realization of complex quantum optical states and information networks. One element that is required for many of these applications is a high-efficiency photon detector capable of photon-number discrimination. We present an integrated photonic system in the telecom band at 1550 nm based on UV-written silica-on-silicon waveguides and modified transition-edge sensors capable of number resolution and over 40 % efficiency. Exploiting the mode transmission failure of these devices, we multiplex three detectors in series to demonstrate a combined 79 % ± 2 % detection efficiency with a single pass, and 88 % ± 3 % at the operating wavelength of an on-chip terminal reflection grating. Furthermore, our optical measurements clearly demonstrate no significant unexplained loss in this system due to scattering or reflections. This waveguide and detector design therefore allows the placement of number-resolving single-photon detectors of predictable efficiency at arbitrary locations within a photonic circuit - a capability that offers great potential for many quantum optical applications. PMID:24104153

  7. REVSTAT Statistical Journal Volume 6, Number 1, March 2008, 83100

    E-print Network

    Alves, Maria Isabel Fraga

    , an approach engraved in the POT method. Our aim here is to give a brief overview of several well-known testingREVSTAT ­ Statistical Journal Volume 6, Number 1, March 2008, 83­100 TESTING EXTREME VALUE a brief overview about several tests published in the context of statistical choice of extreme value

  8. Photon number amplification/duplication through parametric conversion

    NASA Technical Reports Server (NTRS)

    Dariano, G. M.; Macchiavello, C.; Paris, M.

    1993-01-01

    The performance of parametric conversion in achieving number amplification and duplication is analyzed. It is shown that the effective maximum gains G(sub *) remain well below their integer ideal values, even for large signals. Correspondingly, one has output Fano factors F(sub *) which are increasing functions of the input photon number. On the other hand, in the inverse (deamplifier/recombiner) operating mode quasi-ideal gains G(sub *) and small factors F(sub *) approximately equal to 10 percent are obtained. Output noise and non-ideal gains are ascribed to spontaneous parametric emission.

  9. Multiphoton communication in lossy channels with photon-number entangled states

    NASA Astrophysics Data System (ADS)

    Usenko, Vladyslav C.; Paris, Matteo G. A.

    2007-04-01

    We address binary and quaternary communication channels based on correlated multiphoton two-mode states of radiation in the presence of losses. The protocol are based on photon number correlations and realized upon choosing a shared set of thresholds to convert the outcome of a joint photon number measurement into a symbol from a discrete alphabet. In particular, we focus on channels built using feasible photon-number entangled states (PNES) as two-mode coherently-correlated (TMC) or twin-beam (TWB) states and compare their performances with that of channels built using feasible classically correlated (separable) states. We found that PNES provide larger channel capacity in the presence of loss, and that TWB-based channels may transmit a larger amount of information than TMC-based ones at fixed energy and overall loss. Optimized bit discrimination thresholds, as well as the corresponding maximized mutual information, are explicitly evaluated as a function of the beam intensity and the loss parameter. The propagation of TMC and TWB in lossy channels is analyzed and the joint photon number distribution is evaluated, showing that the beam statistics, either sub-Poissonian for TMC or super-Poissonian for TWB, is not altered by losses. Although entanglement is not strictly needed to establish the channels, which are based on photon-number correlations owned also by separable mixed states, purity of the support state is relevant to increase security. The joint requirement of correlation and purity individuates PNES as a suitable choice to build effective channels. The effects of losses on channel security are briefly discussed.

  10. Multiphoton communication in lossy channels with photon-number entangled states

    E-print Network

    Vladyslav C. Usenko; Matteo G. A. Paris

    2008-01-06

    We address binary and quaternary communication channels based on correlated multiphoton two-mode states of radiation in the presence of losses. The protocol are based on photon number correlations and realized upon choosing a shared set of thresholds to convert the outcome of a joint photon number measurement into a symbol from a discrete alphabet. In particular, we focus on channels build using feasible photon-number entangled states (PNES) as two-mode coherently-correlated (TMC) or twin-beam (TWB) states and compare their performances with that of channels built using feasible classically correlated (separable) states. We found that PNES provide larger channel capacity in the presence of loss, and that TWB-based channels may transmit a larger amount of information than TMC-based ones at fixed energy and overall loss. Optimized bit discrimination thresholds, as well as the corresponding maximized mutual information, are explicitly evaluated as a function of the beam intensity and the loss parameter. The propagation of TMC and TWB in lossy channels is analyzed and the joint photon number distribution is evaluated, showing that the beam statistics, either sub-Poissonian for TMC or super-Poissonian for TWB, is not altered by losses. Although entanglement is not strictly needed to establish the channels, which are based on photon-number correlations owned also by separable mixed states, purity of the support state is relevant to increase security. The joint requirement of correlation and purity individuates PNES as a suitable choice to build effective channels. The effects of losses on channel security are briefly discussed.

  11. Predicting landfalling hurricane numbers from basin hurricane numbers: basic statistical analysis

    E-print Network

    Laepple, T; Penzer, J; Bellone, E; Nzerem, K; Laepple, Thomas; Jewson, Stephen; Penzer, Jeremy; Bellone, Enrica; Nzerem, Kechi

    2007-01-01

    One possible method for predicting landfalling hurricane numbers is to first predict the number of hurricanes in the basin and then convert that prediction to a prediction of landfalling hurricane numbers using an estimated proportion. Should this work better than just predicting landfalling hurricane numbers directly? We perform a basic statistical analysis of this question in the context of a simple abstract model.

  12. Superconducting parallel nanowire detector with photon number resolving functionality

    E-print Network

    Marsili, F; Fiore, A; Gaggero, A; Leoni, R; Mattioli, F; Divochiy, A; Korneev, A; Seleznev, V; Kaurova, N; Minaeva, O; Goltsman, G

    2008-01-01

    We present a new photon number resolving detector (PNR), the Parallel Nanowire Detector (PND), which uses spatial multiplexing on a subwavelength scale to provide a single electrical output proportional to the photon number. The basic structure of the PND is the parallel connection of several NbN superconducting nanowires (100 nm-wide, few nm-thick), folded in a meander pattern. Electrical and optical equivalents of the device were developed in order to gain insight on its working principle. PNDs were fabricated on 3-4 nm thick NbN films grown on sapphire (substrate temperature TS=900C) or MgO (TS=400C) substrates by reactive magnetron sputtering in an Ar/N2 gas mixture. The device performance was characterized in terms of speed and sensitivity. The photoresponse shows a full width at half maximum (FWHM) as low as 660ps. PNDs showed counting performance at 80 MHz repetition rate. Building the histograms of the photoresponse peak, no multiplication noise buildup is observable and a one photon quantum efficienc...

  13. On-chip, photon-number-resolving, telecom-band detectors for scalable photonic information processing

    E-print Network

    Gerrits, Thomas; Gates, James C; Lita, Adriana E; Metcalf, Benjamin J; Calkins, Brice; Tomlin, Nathan A; Fox, Anna E; Linares, Antía Lamas; Spring, Justin B; Langford, Nathan K; Mirin, Richard P; Smith, Peter G R; Walmsley, Ian A; Nam, Sae Woo

    2011-01-01

    Integration is currently the only feasible route towards scalable photonic quantum processing devices that are sufficiently complex to be genuinely useful in computing, metrology, and simulation. Embedded on-chip detection will be critical to such devices. We demonstrate an integrated photon-number resolving detector, operating in the telecom band at 1550 nm, employing an evanescently coupled design that allows it to be placed at arbitrary locations within a planar circuit. Up to 5 photons are resolved in the guided optical mode via absorption from the evanescent field into a tungsten transition-edge sensor. The detection efficiency is 7.2 \\pm 0.5 %. The polarization sensitivity of the detector is also demonstrated. Detailed modeling of device designs shows a clear and feasible route to reaching high detection efficiencies.

  14. Observation of squeezed states with strong photon-number oscillations

    SciTech Connect

    Mehmet, Moritz [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut) and Institut fuer Gravitationsphysik, Leibniz Universitaet Hannover, Callinstrasse 38, D-30167 Hannover (Germany); Centre for Quantum Engineering and Space-Time Research (QUEST), Leibniz Universitaet Hannover, Welfengarten 1, D-30167 Hannover (Germany); Vahlbruch, Henning; Lastzka, Nico; Danzmann, Karsten; Schnabel, Roman [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut) and Institut fuer Gravitationsphysik, Leibniz Universitaet Hannover, Callinstrasse 38, D-30167 Hannover (Germany)

    2010-01-15

    Squeezed states of light constitute an important nonclassical resource in the field of high-precision measurements, for example, gravitational wave detection, as well as in the field of quantum information, for example, for teleportation, quantum cryptography, and distribution of entanglement in quantum computation networks. Strong squeezing in combination with high purity, high bandwidth, and high spatial mode quality is desirable in order to achieve significantly improved performances contrasting any classical protocols. Here we report on the observation of 11.5 dB of squeezing, together with relatively high state purity corresponding to a vacuum contribution of less than 5%, and a squeezing bandwidth of about 170 MHz. The analysis of our squeezed states reveals a significant production of higher-order pairs of quantum-correlated photons and the existence of strong photon-number oscillations.

  15. AN AUTOMATED STATISTICAL ANALYSIS APPROACH TO NOISE REDUCTION FOR PHOTON-COUNTING LIDAR SYSTEMS

    E-print Network

    Kerekes, John

    AN AUTOMATED STATISTICAL ANALYSIS APPROACH TO NOISE REDUCTION FOR PHOTON-COUNTING LIDAR SYSTEMS K noisy data, as noise in the detector or reflected solar photons can trigger false returns. An effective noise reduction algorithm is, therefore, essential to proper analysis of photon-counting lidar data. 2

  16. A Superposition Technique for Deriving Photon Scattering Statistics in Plane-Parallel Cloudy Atmospheres

    NASA Technical Reports Server (NTRS)

    Platnick, S.

    1999-01-01

    Photon transport in a multiple scattering medium is critically dependent on scattering statistics, in particular the average number of scatterings. A superposition technique is derived to accurately determine the average number of scatterings encountered by reflected and transmitted photons within arbitrary layers in plane-parallel, vertically inhomogeneous clouds. As expected, the resulting scattering number profiles are highly dependent on cloud particle absorption and solar/viewing geometry. The technique uses efficient adding and doubling radiative transfer procedures, avoiding traditional time-intensive Monte Carlo methods. Derived superposition formulae are applied to a variety of geometries and cloud models, and selected results are compared with Monte Carlo calculations. Cloud remote sensing techniques that use solar reflectance or transmittance measurements generally assume a homogeneous plane-parallel cloud structure. The scales over which this assumption is relevant, in both the vertical and horizontal, can be obtained from the superposition calculations. Though the emphasis is on photon transport in clouds, the derived technique is applicable to any scattering plane-parallel radiative transfer problem, including arbitrary combinations of cloud, aerosol, and gas layers in the atmosphere.

  17. On the Euclidean Version of the Photon Number Integral

    E-print Network

    S. Ruijsenaars; L. Stodolsky

    2007-10-23

    We reconsider the Euclidean version of the photon number integral introduced in ref 1. This integral is well defined for any smooth non-self-intersecting curve in $\\R^N$. Besides studying general features of this integral (including it s conformal invariance), we evaluate it explicitly for the ellipse. The result is $n_{ellipse}=(\\xi^{-1}+\\xi)\\pi^2$, where $\\xi$ is the ratio of the minor and major axes. This is in agreement with the previous result $n_{circle}=2\\pi^2$ and also with the conjecture that the minimum value of $n$ for any plane curve occurs for the circle.

  18. A photon counting detector model based on increment matrices to simulate statistically correct detector signals

    NASA Astrophysics Data System (ADS)

    Faby, Sebastian; Maier, Joscha; Simons, David; Schlemmer, Heinz-Peter; Lell, Michael; Kachelrieß, Marc

    2015-03-01

    We present a novel increment matrix concept to simulate the correlations in an energy-selective photon counting detector. Correlations between the energy bins of neighboring detector pixels are introduced by scattered and fluorescence photons, together with the broadening of the induced charge clouds as they travel towards the electrodes, leading to charge sharing. It is important to generate statistically correct detector signals for the different energy bins to be able to realistically assess the detector's performance in various tasks, e.g. material decomposition. Our increment matrix concept describes the counter increases in neighboring pixels on a single event level. Advantages of our model are the fact that much less random numbers are required than simulating single photons and that the increment matrices together with their probabilities have to be generated only once and can be stored for later use. The different occurring increment matrix sets and the corresponding probabilities are simulated using an analytic model of the photon-matter-interactions based on the photoelectric effect and Compton scattering, and the charge cloud drift, featuring thermal diffusion and Coulomb expansion of the charge cloud. The results obtained with this model are evaluated in terms of the spectral response for different detector geometries and the resulting energy bin sensitivity. Comparisons to published measured data and a parameterized detector model show both a good qualitative and quantitative agreement. We also studied the resulting covariance of reconstructed energy bin images.

  19. Quantum communication with photon-number entangled states and realistic photodetection

    NASA Astrophysics Data System (ADS)

    Usenko, Vladyslav C.; Paris, Matteo G. A.

    2010-03-01

    We address the effects of realistic photodetection, with nonunit quantum efficiency and background noise (dark counts), on the performances of quantum communication schemes based on photon-number entangled states (PNES). We consider channels based on Gaussian twin-beam states (TWB) and non-Gaussian two-mode coherent states (TMC) and evaluate the channel capacity by optimizing the bit discrimination threshold. We found that TWB-based channels are more robust against noise than TMC-based ones and that this result is almost independent on the statistics of dark counts.

  20. Physics and application of photon number resolving detectors based on superconducting parallel nanowires

    E-print Network

    Marsili, F; Gaggero, A; Jahanmirinejad, S; Leoni, R; Mattioli, F; Fiore, A

    2009-01-01

    The Parallel Nanowire Detector (PND) is a photon number resolving (PNR) detector which uses spatial multiplexing on a subwavelength scale to provide a single electrical output proportional to the photon number. The basic structure of the PND is the parallel connection of several NbN superconducting nanowires (100 nm-wide, few nm-thick), folded in a meander pattern. PNDs were fabricated on 3-4 nm thick NbN films grown on MgO (TS=400C) substrates by reactive magnetron sputtering in an Ar/N2 gas mixture. The device performance was characterized in terms of speed and sensitivity. PNDs showed a counting rate of 80 MHz and a pulse duration as low as 660ps full width at half maximum (FWHM). Building the histograms of the photoresponse peak, no multiplication noise buildup is observable. Electrical and optical equivalent models of the device were developed in order to study its working principle, define design guidelines, and develop an algorithm to estimate the photon number statistics of an unknown light. In partic...

  1. A brief history of numbers and statistics with cytometric applications.

    PubMed

    Watson, J V

    2001-02-15

    A brief history of numbers and statistics traces the development of numbers from prehistory to completion of our current system of numeration with the introduction of the decimal fraction by Viete, Stevin, Burgi, and Galileo at the turn of the 16th century. This was followed by the development of what we now know as probability theory by Pascal, Fermat, and Huygens in the mid-17th century which arose in connection with questions in gambling with dice and can be regarded as the origin of statistics. The three main probability distributions on which statistics depend were introduced and/or formalized between the mid-17th and early 19th centuries: the binomial distribution by Pascal; the normal distribution by de Moivre, Gauss, and Laplace, and the Poisson distribution by Poisson. The formal discipline of statistics commenced with the works of Pearson, Yule, and Gosset at the turn of the 19th century when the first statistical tests were introduced. Elementary descriptions of the statistical tests most likely to be used in conjunction with cytometric data are given and it is shown how these can be applied to the analysis of difficult immunofluorescence distributions when there is overlap between the labeled and unlabeled cell populations. PMID:11241502

  2. REVSTAT Statistical Journal Volume 8, Number 2, November 2010, 105124

    E-print Network

    Alves, Maria Isabel Fraga

    REVSTAT ­ Statistical Journal Volume 8, Number 2, November 2010, 105­124 OPTIMIZED CLUSTERS of EDF's (the French electrical company) portfolio fol- lowing the liberalization of the electrical of the whole global signal. The strategy is to optimize, a preliminary clustering of individual load curves

  3. REVSTAT Statistical Journal Volume 11, Number 1, March 2013, 4565

    E-print Network

    Alves, Maria Isabel Fraga

    REVSTAT ­ Statistical Journal Volume 11, Number 1, March 2013, 45­65 USE OF SURVIVAL MODELS increasingly useful in industrial engineering. From plant design reliability to equipment analysis of Survival Models in a Refinery 47 1. INTRODUCTION As industries became more competitive, their methods

  4. Spin-statistics-quantum number connection and supersymmetry

    E-print Network

    Richard M. Weiner

    2013-02-05

    The analogy between the Skyrme and Higgs field leads to the conjecture that all fermions are skyrmions and thus always carry conserved quantum numbers, which are identified with baryon or lepton quantum numbers. This connection between spin and quantum numbers, which parallels the connection between spin and statistics due to the Pauli principle, may explain why supersymmetry has not been observed. Creation of s-particles at higher than present energies due to a breakdown of the Skyrme mechanism might imply the violation of the exclusion principle.

  5. Two dimensional photonic quasicrystal edge states protected by second Chern number

    E-print Network

    Zhang, Xiao

    2015-01-01

    Topological physics in photonic systems have attracted great attentions in recent years. In this work, we theoretically study the one and two dimensional photonic quasicrystal resonator lattices characterized by the first and second Chern number, which show exotic boundary states within the photonic energy band gap. In particular, the second Chern number protected edge states has opened up new possibilities for realizing topological physics of dimensions higher than three in photonic systems, which is highly sought for. Such photonic systems can be easily experimentally realized in regular photonic crystal with dielectric rods in air, by varying the radius of the rods, so we propose experiments realizing our predictions.

  6. Photon-number-solving Decoy State Quantum Key Distribution

    E-print Network

    Qing-yu Cai; Yong-gang Tan

    2005-10-11

    In this paper, a photon-number-resolving decoy state quantum key distribution scheme is presented based on recent experimental advancements. A new upper bound on the fraction of counts caused by multiphoton pulses is given. This upper bound is independent of intensity of the decoy source, so that both the signal pulses and the decoy pulses can be used to generate the raw key after verified the security of the communication. This upper bound is also the lower bound on the fraction of counts caused by multiphoton pulses as long as faint coherent sources and high lossy channels are used. We show that Eve's coherent multiphoton pulse (CMP) attack is more efficient than symmetric individual (SI) attack when quantum bit error rate is small, so that CMP attack should be considered to ensure the security of the final key. finally, optimal intensity of laser source is presented which provides 23.9 km increase in the transmission distance. 03.67.Dd

  7. Photon statistics of coherent harmonic radiation of a linac free electron laser

    Microsoft Academic Search

    Teng Chen

    1999-01-01

    The subject of statistical fluctuations in a free electron laser (FEL) is both fundamental and significant to the understanding of FEL radiation. This dissertation deals with two relevant issues in this regard: the photon statistics of the visible coherent spontaneous harmonic radiation (CSHR); and the examination of the electron shot-noise interpretation of the observed statistical fluctuations. In this dissertation, we

  8. Photon-number-resolving detection at a telecommunications wavelength with a charge-integration photon detector.

    PubMed

    Fujiwara, Mikio; Sasaki, Masahide

    2006-03-15

    We demonstrate multiphoton discrimination at a telecommunications wavelength with the readout frequency of 40 Hz by a charge-integration photon detector (CIPD). The CIPD consists of an InGaAs pin photodiode and a GaAs junction field effect transistor as a preamplifier in a charge-integration circuit, which is cooled to 4.2 K to reduce thermal noise. The quantum efficiency of the CIPD (the detector itself) is 80% for 1530 nm light, and the readout noise is measured as 0.26 electrons at 40 Hz. We can construct Poisson distributions of photocarrier numbers with distinct peaks at each photocarrier number, corresponding to a signal-to-noise ratio of about 3. PMID:16544592

  9. Observation of sub-Poisson Photon Statistics in the Cavity-QED Microlaser Wonshik Choi,1

    E-print Network

    Fang-Yen, Christopher

    Observation of sub-Poisson Photon Statistics in the Cavity-QED Microlaser Wonshik Choi,1 Jai) We have measured the second-order correlation function of the cavity-QED microlaser output the shot noise limit in precision measurements and creating single photon pulses for quan- tum information

  10. Cooperative effects in photon statistics of molecular dimers with spectral diffusion

    E-print Network

    Mukamel, Shaul

    properties of coupled molecules in organic crystals,1­3 photosynthetic antennae4­6 and J aggregates7 haveCooperative effects in photon statistics of molecular dimers with spectral diffusion Frantisek effort has focused on analyzing the autocorrelation function g 2 and the factorial moments of photon

  11. Statistical detection and imaging of objects hidden in turbid media using ballistic photons

    E-print Network

    Statistical detection and imaging of objects hidden in turbid media using ballistic photons Sina-resolution imaging through scattering media with ballistic photons. We derive the fundamental limits on the accuracy the performance of ballistic and conventional imaging systems. This model is later used to derive optimal single

  12. Statistical Detection and Imaging of Objects Hidden in Turbid Media Using Ballistic Photons

    E-print Network

    Eriksson, Brian

    Statistical Detection and Imaging of Objects Hidden in Turbid Media Using Ballistic Photons Sina through scattering media with "ballistic" photons. We derive the fundamental limits on the accuracy the performance of ballistic and conventional imaging systems. This model is later used to derive optimal single

  13. Practical photon number detection with electric field-modulated silicon avalanche photodiodes

    Microsoft Academic Search

    O. Thomas; Z. L. Yuan; A. J. Shields

    2012-01-01

    Low-noise single-photon detection is a prerequisite for quantum information processing using photonic qubits. In particular, detectors that are able to accurately resolve the number of photons in an incident light pulse will find application in functions such as quantum teleportation and linear optics quantum computing. More generally, such a detector will allow the advantages of quantum light detection to be

  14. Resolving photon number states in a superconducting circuit D. I. Schuster

    E-print Network

    Resolving photon number states in a superconducting circuit D. I. Schuster ,1 A. A. Houck ,1 J. A or absence of even a single photon can have a dramatic effect. This system[2] is called circuit quantum electrodynamics (QED) because it is the circuit equivalent of the atom-photon interaction in cavity QED

  15. Measurement of the photon statistics and the noise figure of a fiber-optic parametric amplifier.

    PubMed

    Voss, Paul L; Tang, Renyong; Kumar, Prem

    2003-04-01

    We report measurement of the noise statistics of spontaneous parametric fluorescence in a fiber parametric amplifier with single-mode, single-photon resolution. We employ optical homodyne tomography for this purpose, which also provides a self-calibrating measurement of the noise figure of the amplifier. The measured photon statistics agree with quantum-mechanical predictions, and the amplifier's noise figure is found to be almost quantum limited. PMID:12696611

  16. Optimization of multi-photon event discrimination levels using Poisson statistics.

    PubMed

    Soukka, Juri; Virkki, Arho; Hänninen, Pekka; Soini, Juhani

    2004-01-12

    In applications where random multi-photon events must be distinguishable from the background, detection of the signals must be based on either analog current measurement or photon counting and multi-level discrimination of single and multi-photon events. In this paper a novel method for optimizing photomultiplier (PMT) pulse discrimination levels in single- and multi-photon counting is demonstrated. This calibration method is based on detection of photon events in coincidence to short laser pulses. The procedure takes advantage of Poisson statistics of single- and mult-iphoton signals and it is applicable to automatic calibration of photon counting devices on production line. Results obtained with a channel photomultiplier (CPM) are shown. By use of three parallel discriminators and setting the discriminator levels according to the described method resulted in a linear response over wide range of random single- and multi-photon signals. PMID:19471514

  17. Quantum Statistical Testing of a Quantum Random Number Generator

    SciTech Connect

    Humble, Travis S [ORNL

    2014-01-01

    The unobservable elements in a quantum technology, e.g., the quantum state, complicate system verification against promised behavior. Using model-based system engineering, we present methods for verifying the opera- tion of a prototypical quantum random number generator. We begin with the algorithmic design of the QRNG followed by the synthesis of its physical design requirements. We next discuss how quantum statistical testing can be used to verify device behavior as well as detect device bias. We conclude by highlighting how system design and verification methods must influence effort to certify future quantum technologies.

  18. Multiphoton communication in lossy channels with photon-number entangled states

    E-print Network

    Usenko, V C; Paris, Matteo G. A.; Usenko, Vladyslav C.

    2006-01-01

    We address M-ary communication channels based on correlated multiphoton two-mode states of radiation in the presence of losses. In particular, we focus on channels build using feasible photon-number entangled states (PNES) as two-mode coherently-correlated (TMC) or twin-beam (TWB) states and compare their performances with that of channels built using feasible classically correlated (separable) states. We found that PNES provide larger channel capacity in the presence of loss, and that TWB-based channels may transmit a larger amount of information than TMC-based ones at fixed energy and overall loss. Optimized bit discrimination thresholds, as well as the corresponding maximized mutual information, are explicitly evaluated as a function of the beam intensity and the loss parameter for binary and quaternary alphabets. The propagation of TMC and TWB in lossy channels is analyzed and the joint photon number distribution is evaluated, showing that the beam statistics, either sub-Poissonian for TMC or super-Poisso...

  19. Advanced Photon Source research: Volume 1, Number 1, April 1998

    SciTech Connect

    NONE

    1998-04-01

    The following articles are included in this publication: (1) The Advanced Photon Source: A Brief Overview; (2) MAD Analysis of FHIT at the Structural Biology Center; (3) Advances in High-Energy-Resolution X-ray Scattering at Beamline 3-ID; (4) X-ray Imaging and Microspectroscopy of the Mycorrhyizal Fungus-Plant Symbiosis; (5) Measurement and Control of Particle-beam Trajectories in the Advanced Photon Storage Ring; (6) Beam Acceleration and Storage at the Advanced Photon Source; and (7) Experimental Facilities Operations and Current Status.

  20. Absolute efficiency estimation of photon-number-resolving detectors using twin beams

    E-print Network

    Worsley, A P; Lundeen, J S; Mosley, P J; Smith, B J; Puentes, G; Thomas-Peter, N; Walmsley, I A; 10.1364/OE.17.004397

    2009-01-01

    A nonclassical light source is used to demonstrate experimentally the absolute efficiency calibration of a photon-number-resolving detector. The photon-pair detector calibration method developed by Klyshko for single-photon detectors is generalized to take advantage of the higher dynamic range and additional information provided by photon-number-resolving detectors. This enables the use of brighter twin-beam sources including amplified pulse pumped sources, which increases the relevant signal and provides measurement redundancy, making the calibration more robust.

  1. Multi-bit quantum random number generation by measuring positions of arrival photons

    NASA Astrophysics Data System (ADS)

    Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun

    2014-10-01

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.

  2. Multi-bit quantum random number generation by measuring positions of arrival photons

    SciTech Connect

    Yan, Qiurong, E-mail: yanqiurong@ncu.edu.cn [Department of Electronics Information Engineering, Nanchang University, Nanchang 330031 (China); State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119 (China); Zhao, Baosheng [State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119 (China); Liao, Qinghong; Zhou, Nanrun [Department of Electronics Information Engineering, Nanchang University, Nanchang 330031 (China)

    2014-10-15

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.

  3. Multi-bit quantum random number generation by measuring positions of arrival photons.

    PubMed

    Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun

    2014-10-01

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator. PMID:25362380

  4. Spatial Resolution Enhancement in Quantum Imaging beyond the Diffraction Limit Using Entangled Photon-Number State

    E-print Network

    Jianming Wen; Morton H. Rubin; Yanhua Shih

    2008-12-12

    In this paper we study the resolution of images illuminated by sources composed of $N+1$ photons in which one non-degenerate photon is entangled with $N$ degenerate photons. The $N$ degenerate photons illuminate an object and are collected by an $N$ photon detector. The signal from the $N$ photon detector is measured in coincidence with the non-degenerate photon giving rise to a ghost image. We discuss the case of three photons in various configurations and generalize to $N+1$. Using the Rayleigh criterion, we find that the system may give an improvement in resolution by a factor of $N$ compared to using a classical source. For the case that the $N$-photon number detector is a point detector, a coherent image is obtained. If the $N$-photon detector is a bucket detector, the image is incoherent. The visibility of the image in both cases is 1. In the opposite case in which the non-degenerate photon is scattered by the object, then, using an $N$-photon point detector may reduce the Airy disk by a factor of $N$.

  5. Photon number resolving SiPM detector with 1 GHz count rate.

    PubMed

    Akiba, M; Inagaki, K; Tsujino, K

    2012-01-30

    We demonstrate 1 GHz count rate photon detection with photon number resolution by using a multi-pixel photon counter (MPPC) and performing baseline correction. A bare MPPC chip mounted on a high-frequency circuit board is employed to increase response speed. The photon number resolving capability is investigated at high repetition rates. This capability remains at a repetition rate of 1 GHz and at rates as high as an average of 2.6 photons detected per optical pulse. The photon detection efficiencies are 16% at ? = 450 nm and 4.5% at ? = 775 nm with a dark count rate of 270 kcps and an afterpulse probability of 0.007. PMID:22330514

  6. Random number generation based on the time of arrival of single photons.

    PubMed

    Ma, Hai-Qiang; Xie, Yuejian; Wu, Ling-An

    2005-12-20

    We report the demonstration of a new type of true random number generator based on the random distribution of the time interval between photons from a single-photon-like source. The experimental setup is simple and robust against mechanical and temperature disturbances. With improved detector resolution and efficiency, the random number bit rate could be increased by more than an order of magnitude to satisfy practical requirements. PMID:16381524

  7. Random number generation based on the time of arrival of single photons

    NASA Astrophysics Data System (ADS)

    Ma, Hai-Qiang; Xie, Yuejian; Wu, Ling-An

    2005-12-01

    We report the demonstration of a new type of true random number generator based on the random distribution of the time interval between photons from a single-photon-like source. The experimental setup is simple and robust against mechanical and temperature disturbances. With improved detector resolution and efficiency, the random number bit rate could be increased by more than an order of magnitude to satisfy practical requirements.

  8. Practical photon number detection with electric field-modulated silicon avalanche photodiodes.

    PubMed

    Thomas, O; Yuan, Z L; Shields, A J

    2012-01-01

    Low-noise single-photon detection is a prerequisite for quantum information processing using photonic qubits. In particular, detectors that are able to accurately resolve the number of photons in an incident light pulse will find application in functions such as quantum teleportation and linear optics quantum computing. More generally, such a detector will allow the advantages of quantum light detection to be extended to stronger optical signals, permitting optical measurements limited only by fluctuations in the photon number of the source. Here we demonstrate a practical high-speed device, which allows the signals arising from multiple photon-induced avalanches to be precisely discriminated. We use a type of silicon avalanche photodiode in which the lateral electric field profile is strongly modulated in order to realize a spatially multiplexed detector. Clearly discerned multiphoton signals are obtained by applying sub-nanosecond voltage gates in order to restrict the detector current. PMID:22273682

  9. Noise figure and photon statistics in coherent anti-Stokes Raman scattering

    E-print Network

    Jalali. Bahram

    ://www.ee.ucla.edu/~oecs/ Abstract: Coherent anti-Stokes Raman scattering (CARS) is a well-known Raman scattering process that occurs-Stokes waves in CARS and show its dependence on phase mismatch. Under phase matched conditions, the minimum, refractive indices, and nonlinear susceptibilities. We calculate the photon statistics of CARS and show

  10. Statistics of scattered photons from a driven three-level emitter in 1D open space

    SciTech Connect

    Roy, Dibyendu [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bondyopadhaya, Nilanjan [Integrated Science Education and Research Centre, Visva-Bharati University, Santiniketan (India)

    2014-01-07

    We derive the statistics of scattered photons from a - or ladder-type three-level emitter (3LE) embedded in a 1D open waveguide. The weak probe photons in the waveguide are coupled to one of the two allowed transitions of the 3LE, and the other transition is driven by a control beam. This system shows electromagnetically induced transparency (EIT) which is accompanied with the Autler-Townes splitting (ATS) at a strong driving by the control beam, and some of these effects have been observed recently. We show that the nature of second-order coherence of the transmitted probe photons near two-photon resonance changes from bunching to antibunching to constant as strength of the control beam is ramped up from zero to a higher value where the ATS appears.

  11. A bias-free quantum random number generation using photon arrival time selectively

    E-print Network

    Jian-min Wang; Tian-yu Xie; Hong-fei Zhang; Dong-xu Yang; Chao Xie; Jian Wang

    2015-05-20

    We present a high-quality, bias-free quantum random number generator (QRNG) using photon arrival time selectively in accordance with the number of photon detection events within a sampling time interval in attenuated light. It is well showed in both theoretical analysis and experiments verification that this random number production method eliminates both bias and correlation perfectly without more post processing and the random number can clearly pass the standard randomness tests. We fulfill theoretical analysis and experimental verification of the method whose rate can reach up to 45Mbps.

  12. The Number of Guttman Errors as a Simple and Powerful Person-Fit Statistic.

    ERIC Educational Resources Information Center

    Meijer, Rob R.

    1994-01-01

    Through simulation, the power of the U3 statistic was compared with the power of one of the simplest person-fit statistics, the sum of the number of Guttman errors. In most cases, a weighted version of the latter statistic performed as well as the U3 statistic. (SLD)

  13. A chaotic photonic integrated circuit for Gb\\/s true random number generation

    Microsoft Academic Search

    Stavros Deligiannidis; Evangelos Pikasis; Apostolos Argyris; Adonis Bogris; D. Syvridis

    2010-01-01

    Broadband chaotic signals generated by a photonic integrated circuit are employed to provide true random bit streams at Gb\\/s rates. Chaotic waveforms with appropriate spectral distribution and statistics succeed, after sampling, to pass randomness tests specified by NIST organization.

  14. Statistical Error in Particle Simulations of Low Mach Number Flows

    E-print Network

    Hadjiconstantinou, Nicolas G.

    We present predictions for the statistical error due to finite sampling in the presence of thermal fluctuations in molecular simulation algorithms. Expressions for the fluid velocity, density and temperature are derived ...

  15. REVSTAT Statistical Journal Volume 11, Number 3, November 2013, 317338

    E-print Network

    Alves, Maria Isabel Fraga

    LOGISTIC DISTRIBUTION Authors: A. Asgharzadeh ­ Department of Statistics, University of Mazandaran Babolsar Abstract: · In this paper, we introduce a generalized skew logistic distribution that contains the usual skew logistic distribution as a special case. Several mathematical properties of the distribution

  16. Crunching Numbers: What Cancer Screening Statistics Really Tell Us

    Cancer.gov

    Cancer screening studies have shown that more screening does not necessarily translate into fewer cancer deaths. This article explains how to interpret the statistics used to describe the results of screening studies.

  17. Design of Narrowband Optical Filters Using Binary Number Sequence Photonic Crystals

    NASA Astrophysics Data System (ADS)

    Banerjee, Anirudh

    2008-11-01

    A theory to design narrow band optical filters by using a new photonic crystal structure is presented. This new photonic crystal structure is composed of low index layers and high index layers arranged in mod. 4 up and down binary number sequence. The new structure exhibits narrow transmission peaks in the forbidden frequency gap region with high optical transmission (greater than 99.98%) at C.W.D.M. (Coarse Wavelength Division Multiplexing) center wavelengths. The proposed filters use only 8 layers. These new binary number sequence photonic crystal narrowband optical filters are much smaller in size, lower in cost and easier to fabricate as compared to narrowband photonic crystal optical filters based on defect Fractal Cantor multilayers, suggested recently by a group of researchers.

  18. Effects of dead time and afterpulses in photon detector on measured statistics of stochastic radiation.

    PubMed

    Kornilov, Victor

    2014-01-01

    Many physical experiments require analysis of the statistics of fluctuating radiation. In the case of an ideal single-photon detector, the contribution of photon noise to the statistics of the registered signal has been thoroughly examined. However, practical photon counters have a dead time, leading to miscounting of certain true events, and sometimes the counters generate false afterpulses. This study investigates the impact of these two effects, and it presents the theoretical relations between the statistical moments of the radiation and the registered counts while also accounting for dead time and the probability of afterpulses. Expressions for statistical moments of any order are obtained on the basis of the generalized Poisson distribution. For counters with paralyzable dead time, alternative relations for the mean and variance are derived using generally accepted formulas. As an example, the measurements of stellar scintillation and the result of a simple experiment are considered. The results of the experimental verification of the theoretical expression confirm the need to account for the nonideal nature of detectors in almost all similar measurements. PMID:24561933

  19. Effects of dead time and afterpulses in photon detector on measured statistics of stochastic radiation

    NASA Astrophysics Data System (ADS)

    Kornilov, Victor

    2014-01-01

    Many physical experiments require analysis of the statistics of fluctuating radiation. In the case of an ideal single-photon detector, the contribution of photon noise to the statistics of the registered signal has been thoroughly examined. However, practical photon counters have a dead time, leading to miscounting of certain true events, and sometimes the counters generate false after-pulses. This study investigate the impact of these two effects, and it presents the theoretical relations between the statistical moments of the radiation and the registered counts while also accounting for dead time and the probability of after-pulses. Expressions for statistical moments of any order are obtained on the basis of the generalized Poisson distribution (GPD). For counters with paralyzable dead time, alternative relations for the mean and variance are derived using generally accepted formulas. As an example, the measurements of stellar scintillation and the result of simple experiment are considered. The results of the experimental verification of the theoretical expression confirm the need to account for the non-ideal nature of detectors in almost all similar measurements.

  20. Temporal Dynamics and Nonclassical Photon Statistics of Quadratically Coupled Optomechanical Systems

    NASA Astrophysics Data System (ADS)

    Singh, Shailendra Kumar; Muniandy, S. V.

    2015-05-01

    Quantum optomechanical system serves as an interface for coupling between photons and phonons due to mechanical oscillations. We used the Heisenberg-Langevin approach under Markovian white noise approximation to study a quadratically coupled optomechanical system which contains a thin dielectric membrane quadratically coupled to the cavity field. A decorrelation method is employed to solve for a larger number of coupled equations. Transient mean numbers of cavity photons and phonons that provide dynamical behaviour are computed for different coupling regime. We have also obtained the two-boson second-order correlation functions for the cavity field, membrane oscillator and their cross correlations that provide nonclassical properties governed by quadratic optomechanical system.

  1. Temporal Dynamics and Nonclassical Photon Statistics of Quadratically Coupled Optomechanical Systems

    E-print Network

    Shailendra Kumar Singh; S. V. Muniandy

    2015-06-24

    Quantum optomechanical system serves as an interface for coupling between photons and phonons due to mechanical oscillations. We used the Heisenberg-Langevin approach under Markovian white noise approximation to study a quadratically coupled optomechanical system which contains a thin dielectric membrane quadratically coupled to the cavity field. A decorrelation method is employed to solve for a larger number of coupled equations. Transient mean numbers of cavity photons and phonons that provide dynamical behaviour are computed for different coupling regime. We have also obtained the two-boson second-order correlation functions for the cavity field, membrane oscillator and their cross correlations that provide nonclassical properties governed by quadratic optomechanical system.

  2. Eigenvalue decomposition method for photon statistics of frequency filtered fields and its applications to quantum dot emitters

    E-print Network

    Kamide, Kenji; Arakawa, Yasuhiko

    2015-01-01

    A simple calculation method for photon statistics of frequency-filtered fields is proposed. This method, based on eigenvalue decompositions of superoperators, allows us to study effects on the photon statistics of spectral filtering by various types of filters, such as Gaussian and rectangular filters as well as Lorentzian filters, which is not possible by conventional approaches. As an example, this method is applied to a simulation of quantum dot single-photon emitters, where we found the efficient choice of the filter types to have pure single photons depends on the excitation conditions i.e. incoherent or coherent (and resonant) excitations.

  3. Distinguishing dark matter from unresolved point sources in the Inner Galaxy with photon statistics

    NASA Astrophysics Data System (ADS)

    Lee, Samuel K.; Lisanti, Mariangela; Safdi, Benjamin R.

    2015-05-01

    Data from the Fermi Large Area Telescope suggests that there is an extended excess of GeV gamma-ray photons in the Inner Galaxy. Identifying potential astrophysical sources that contribute to this excess is an important step in verifying whether the signal originates from annihilating dark matter. In this paper, we focus on the potential contribution of unresolved point sources, such as millisecond pulsars (MSPs). We propose that the statistics of the photons—in particular, the flux probability density function (PDF) of the photon counts below the point-source detection threshold—can potentially distinguish between the dark-matter and point-source interpretations. We calculate the flux PDF via the method of generating functions for these two models of the excess. Working in the framework of Bayesian model comparison, we then demonstrate that the flux PDF can potentially provide evidence for an unresolved MSP-like point-source population.

  4. USA by Numbers: A Statistical Portrait of the United States.

    ERIC Educational Resources Information Center

    Weber, Susan, Ed.

    This book presents demographic data about a variety of U.S. public policies, social problems, and environmental issues. The issues and problems that the statistics illustrate (such as overflowing garbage dumps, homelessness, child poverty, and smog and water pollution) are connected with, and the consequences of, the expanding U.S. population. The…

  5. Elementary Business Statistics Unique Number 04380, 04385, 04390

    E-print Network

    Ghosh, Joydeep

    . Site activities will include submission of homework assignments and posting of grades. Login from the ACITS Help Desk (475-9400). Alternatively, you may need to work in the CBA labs. HOMEWORK but they are a necessary requirement. Your proficiency with statistics will improve with active practice; i.e., working

  6. REVSTAT Statistical Journal Volume 2, Number 1, June 2004

    E-print Network

    Alves, Maria Isabel Fraga

    of the generalized Pareto distribution in Statistics (e.g., analysis of POT data) we propose a test for testing PARETO -- A RESISTANT AND ROBUST TEST Authors: M.F. Brilhante ­ Department of Mathematics, University)/(M -FL) for testing exponentiality versus generalized Pareto, where FU , FL and M are, respec- tively

  7. Disabilities among Children. Disability Statistics Abstract, Number 15.

    ERIC Educational Resources Information Center

    Wenger, Barbara L.; And Others

    This abstract summarizes recent statistics on the prevalence and causes of disability among U.S. children, based on data from the 1992 National Health Interview Survey, a household survey of the noninstitutionalized U.S. population. Analysis indicates that there are difficulties in comparing disability prevalence across age groups; overall, 5.5…

  8. Learning to Read the Numbers: A Critical Orientation toward Statistics

    ERIC Educational Resources Information Center

    Whitin, Phyllis; Whitin, David J.

    2008-01-01

    Being a critical reader of data is an integral part of being fully literate in today's information age. In this article the authors underscore the interdisciplinary importance of this stance by drawing upon theoretical perspectives from both the fields of language and mathematics. They argue that all texts, including statistical ones, must be…

  9. REVSTAT Statistical Journal Volume 7, Number 1, April 2009, 87104

    E-print Network

    Alves, Maria Isabel Fraga

    NONSTATIONARY SEQUENCES: THE ANALYSIS OF THE BUSINESS CYCLE Author: D.S.G. Pollock ­ Department of Economics. The classical theory of statistical Fourier analysis deals with stationary stochastic sequences of unlimited is based. In business cycle analysis, one is faced, by contrast, with macroeconomic sequences

  10. Posting Number: 0601800 Title: Assist/Assoc/Full Professor (Applied Statistics/Biostatistics)

    E-print Network

    Shepp, Larry

    Posting Number: 0601800 Title: Assist/Assoc/Full Professor (Applied Statistics/Biostatistics) Working Title: Assist/Assoc/Full Professor (Applied Statistics/Biostatistics) Department: Mathematical in the general area of Applied Statistics/Biostatistics. The Department is particularly interested in candidates

  11. Volume 11 Number 7 1983 Nucleic Acids Research Statistical characterizationof nucleic acid sequence functional domains

    E-print Network

    Waterman, Michael S.

    Volume 11 Number 7 1983 Nucleic Acids Research Statistical characterizationof nucleic acid sequence among these domains but suggest others. The ability of these simple statistics of nucleic acid sequences body of nucleic acid sequence data. In this study we review the statistical characteristics

  12. The Statistics of the Number of Neutron Collisions Prior to Absorption

    E-print Network

    Pázsit, Imre

    The Statistics of the Number of Neutron Collisions Prior to Absorption Sara A. Pozzi* Oak Ridge Accepted July 25, 2005 Abstract ­ We propose a simple analytical model to describe the statistics, the energy transfer and the collision num- ber are related quantities, and therefore, the statistics of

  13. Set partition statistics and q-Fibonacci numbers

    Microsoft Academic Search

    Adam M. Goyt; Bruce E. Sagan

    2009-01-01

    We consider the set partition statistics ls and r b introduced by Wachs and White and investigate their distribution over set partitions that avoid certain patterns. In particular, we consider those set partitions avoiding the pattern 13=2, n.13=2\\/, and those avoiding both 13=2 and 123, n.13=2; 123\\/. We show that the distribution over n.13=2\\/ enumerates certain integer partitions, and the

  14. Set partition statistics and qFibonacci numbers Adam M. Goyt #

    E-print Network

    Sagan, Bruce

    Set partition statistics and q­Fibonacci numbers Adam M. Goyt # Department of Mathematics Michigan certain integer partitions, and the distribution over # n (13/2, 123) gives q­Fibonacci numbers. These q­Fibonacci numbers are closely related to q­Fibonacci numbers studied by Carlitz and by Cigler. We provide

  15. Optical Cluster-State Generation without Number-Resolving Photon Detectors

    E-print Network

    Wilde, M M; Lee, H; Spedalieri, F; Dowling, Jonathan P.; Lee, Hwang; Spedalieri, Federico; Wilde, Mark M.

    2006-01-01

    We show how to build a controlled-phase gate for linear optical quantum computing by using photon detectors that cannot resolve photon number. Our scheme uses polarization encoding of photons and includes an intrinsic error-correction circuit which can correct for errors introduced by the detectors. We generate a four-qubit ancilla state offline given a source of pure polarization-entangled Bell states. We use the four-qubit ancilla state in the operation of our controlled-phase gate for a success probability of 1/4. A recent result [1, 2] claims that a two-qubit gate with non-zero success probability can build an arbitrarily large cluster state with only polynomial overhead. Thus we can reliably generate optical cluster states without number-resolving detectors and with polynomial overhead if the dark count probability of the detectors is low.

  16. CNTb, a set of scripts for batch processing and statistical analysis of photon correlation spectroscopy data via CONTIN inversion

    E-print Network

    Boyer, Edmond

    1 CNTb, a set of scripts for batch processing and statistical analysis of photon correlation allowing a batch inversion of series of photon correlation spectroscopy data files via CONTIN with a single is needed to test the reproducibility and the reliability of CONTIN output in difficult experimental

  17. REVSTAT Statistical Journal Volume 9, Number 1, March 2011, 99114

    E-print Network

    Alves, Maria Isabel Fraga

    for Multivariate Disease Rates 101 1. INTRODUCTION The literature in spatial epidemiology contains a growing number as implicitly allowing for less restrictive spatial correlation structures between geographical units. We illustrate results of using the model on data taken from cancer registries on four carcinomas in some 300 UK

  18. Direct measurement of heralded single-photon statistics from a parametric down-conversion source

    SciTech Connect

    Hoeckel, David; Koch, Lars; Benson, Oliver [Nano Optics Group, Institute of Physics, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany)

    2011-01-15

    We present a full triple-coincidence analysis of photon-pair states generated by spontaneous parametric down-conversion. By increasing the coherence time of the source with the help of an intracavity setup, our measurements are not spoiled by detection time jitter. Signal-idler, but also thermal signal-signal, correlations are clearly resolved in this regime. Via introduction of an artificial coincidence window, we discuss in detail the transition to the previously studied cases where typically no single-arm correlation is observed. We investigate the heralded antibunching characteristics to show that in our system further studies of continuously generated photon states, possibly higher-photon-number entangled states, can be performed with respect to their (non)applicability in quantum information tasks.

  19. Absolute number of photons produced by alpha-particles in liquid and gaseous xenon

    NASA Astrophysics Data System (ADS)

    Miyajima, Mitsuhiro; Sasaki, Shinichi; Shibamura, Eido

    1992-02-01

    The Ws which is defined as an average energy expended per scintillation photon, was found to be 16.3 ± 0.3 eV for alpha-particles in liquid xenon, and 49.6 ± 1.1 eV in gaseous xenon, respectively. These results followed from the number of photoelectrons measured with a VUV sensitive photomultiplier tube, which was used as a photodiode. The number of photoelectrons from the photomultiplier photocathode was measured absolutely with a well calibrated charge sensitive amplifier system as a function of distance between the alpha-source and the photomultiplier photocathode. The detection geometries included both reflective and nonreflective walls. The data were well fitted to corresponding curves obtained with a Monte Carlo simulation, and yielded the total number of scintillation photons.

  20. Generation of a superposition of odd photon number states for quantum information networks

    E-print Network

    J. S. Neergaard-Nielsen; B. Melholt Nielsen; C. Hettich; K. Moelmer; E. S. Polzik

    2006-05-10

    We report on the experimental observation of quantum-network-compatible light described by a non-positive Wigner function. The state is generated by photon subtraction from a squeezed vacuum state produced by a continuous wave optical parametric amplifier. Ideally, the state is a coherent superposition of odd photon number states, closely resembling a superposition of weak coherent states (a Schroedinger cat), with the leading contribution from a single photon state in the low parametric gain limit. Light is generated in a nearly perfect spatial mode with a Fourier-limited frequency bandwidth which matches well atomic quantum memory requirements. The source is also characterized by high spectral brightness with about 10,000 and more events per second routinely generated. The generated state of light is the ultimate input state for testing quantum memories, quantum repeaters and linear optics quantum computers.

  1. On Statistical Testing of Random Numbers Generators El Haje, F.1

    E-print Network

    Golubev, Yuri

    ) that apply iterative numerical algorithms to an initial seed, 1 #12;· True Random Number Generators (TRNGOn Statistical Testing of Random Numbers Generators El Haje, F.1 , Golubev, Yu.2 , Liardet, P.-Y.3- resents a serious competitor for Maurer's test in the case when the random number generator is governed

  2. A Comparative Study of Gaussian TFA Learning and Statistical Tests on the Factor Number in APT

    E-print Network

    Xu, Lei

    A Comparative Study of Gaussian TFA Learning and Statistical Tests on the Factor Number in APT Kai to be useful for determining factor number k in classical financial APT analysis. In this paper, comparisons of factor number determination using different tech- niques will be shown. Results reveal that TFA

  3. Comparing Data Sets: Implicit Summaries of the Statistical Properties of Number Sets

    ERIC Educational Resources Information Center

    Morris, Bradley J.; Masnick, Amy M.

    2015-01-01

    Comparing datasets, that is, sets of numbers in context, is a critical skill in higher order cognition. Although much is known about how people compare single numbers, little is known about how number sets are represented and compared. We investigated how subjects compared datasets that varied in their statistical properties, including ratio of…

  4. Statistical evaluation of PACSTAT random number generation capabilities

    SciTech Connect

    Piepel, G.F.; Toland, M.R.; Harty, H.; Budden, M.J.; Bartley, C.L.

    1988-05-01

    This report summarizes the work performed in verifying the general purpose Monte Carlo driver-program PACSTAT. The main objective of the work was to verify the performance of PACSTAT's random number generation capabilities. Secondary objectives were to document (using controlled configuration management procedures) changes made in PACSTAT at Pacific Northwest Laboratory, and to assure that PACSTAT input and output files satisfy quality assurance traceability constraints. Upon receipt of the PRIME version of the PACSTAT code from the Basalt Waste Isolation Project, Pacific Northwest Laboratory staff converted the code to run on Digital Equipment Corporation (DEC) VAXs. The modifications to PACSTAT were implemented using the WITNESS configuration management system, with the modifications themselves intended to make the code as portable as possible. Certain modifications were made to make the PACSTAT input and output files conform to quality assurance traceability constraints. 10 refs., 17 figs., 6 tabs.

  5. Statistical Handbook on Aging Americans. 1994 Edition. Statistical Handbook Series Number 5.

    ERIC Educational Resources Information Center

    Schick, Frank L., Ed.; Schick, Renee, Ed.

    This statistical handbook contains 378 tables and charts illustrating the changes in the United States' aging population based on data collected during the 1990 census and several other surveys. The tables and charts are organized by topic as follows: demographics (age and sex distribution, life expectancy, race and ethnicity, geographic…

  6. Effects of dead time and after-pulses in photon detector on measured statistics of stochastic radiation

    E-print Network

    Kornilov, Victor

    2013-01-01

    Many physical experiments require analysis of the statistics of fluctuating radiation. In the case of an ideal single-photon detector, the contribution of photon noise to the statistics of the registered signal has been thoroughly examined. However, practical photon counters have a dead time, leading to miscounting of certain true events, and sometimes the counters generate false after-pulses. This study investigate the impact of these two effects, and it presents the theoretical relations between the statistical moments of the radiation and the registered counts while also accounting for dead time and the probability of after-pulses. Expressions for statistical moments of any order are obtained on the basis of the generalized Poisson distribution (GPD). For counters with paralyzable dead time, alternative relations for the mean and variance are derived using generally accepted formulas. As an example, the measurements of stellar scintillation and the result of simple experiment are considered. The results of...

  7. Measuring photon-photon interactions via photon detection

    SciTech Connect

    Macovei, Mihai A. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2010-12-15

    Strong nonlinearity plays a significant role in physics, particularly in the design of novel quantum sources of light and matter as well as in quantum chemistry and quantum biology. In simple systems, the photon-photon interaction can be determined analytically. However, it becomes challenging to obtain it for more complex systems. Therefore, we show here how to measure strong nonlinearities by allowing the sample to interact with a weakly pumped quantized leaking optical mode. We found that the detected mean photon number versus pump-field frequency shows several peaks. Interestingly, the interval between neighboring peaks equals the photon-photon interaction potential. Furthermore, the system exhibits sub-Poissonian photon statistics, entanglement, and photon switching with less than one photon. Finally, we connect our study with existing experiments.

  8. Direct measurement of sub-wavelength interference using thermal light and photon-number-resolved detection

    SciTech Connect

    Zhai, Yanhua, E-mail: yanhuazhai@gmail.com, E-mail: jfan@nist.gov; Fan, Jingyun, E-mail: yanhuazhai@gmail.com, E-mail: jfan@nist.gov; Migdall, Alan [Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, 100 Bureau Drive, Mail Stop 8441, Gaithersburg, Maryland 20899 (United States); Becerra, Francisco E. [Center for Quantum Information and Control, MSC07-4220, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2014-09-08

    We examine thermal light diffracted through a double slit using photon-number-resolved detection to directly measure high-order spatial correlations, and we see sinusoidal modulations of those correlations. The fringe width can, in principal, be made arbitrarily small, and we have experimentally obtained fringe widths as small as 30?nm with 800?nm wavelength light. This extreme sub-wavelength resolution, along with this direct detection technique, offers potential for high precision measurement applications.

  9. True random number generator based on discretized encoding of the time interval between photons.

    PubMed

    Li, Shen; Wang, Long; Wu, Ling-An; Ma, Hai-Qiang; Zhai, Guang-Jie

    2013-01-01

    We propose an approach to generate true random number sequences based on the discretized encoding of the time interval between photons. The method is simple and efficient, and can produce a highly random sequence several times longer than that of other methods based on threshold or parity selection, without the need for hashing. A proof-of-principle experiment has been performed, showing that the system could be easily integrated and applied to quantum cryptography and other fields. PMID:23456008

  10. Dynamics of dispersive photon-number QND measurements in a micromaser

    SciTech Connect

    Kozlovskii, A. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)], E-mail: kozlovsk@sci.lebedev.ru

    2007-04-15

    A numerical analysis of dispersive quantum nondemolition measurement of the photon number of a microwave cavity field is presented. Simulations show that a key property of the dispersive atom-field interaction used in Ramsey interferometry is the extremely high sensitivity of the dynamics of atomic and field states to basic parameters of the system. When a monokinetic atomic beam is sent through a microwave cavity, a qualitative change in the field state can be caused by an uncontrollably small deviation of parameters (such as atom path length through the cavity, atom velocity, cavity mode frequency detuning, or atom-field coupling constants). The resulting cavity field can be either in a Fock state or in a super-Poissonian state (characterized by a large photon-number variance). When the atoms have a random velocity spread, the field is squeezed to a Fock state for arbitrary values of the system's parameters. However, this makes detection of Ramsey fringes impossible, because the probability of detecting an atom in the upper or lower electronic state becomes a random quantity almost uniformly distributed over the interval between zero and unity, irrespective of the cavity photon number.

  11. Attacks exploiting deviation of mean photon number in quantum key distribution and coin tossing

    E-print Network

    Shihan Sajeed; Igor Radchenko; Sarah Kaiser; Jean-Philippe Bourgoin; Anna Pappa; Laurent Monat; Matthieu Legre; Vadim Makarov

    2015-03-30

    The security of quantum communication using a weak coherent source requires an accurate knowledge of the source's mean photon number. Finite calibration precision or an active manipulation by an attacker may cause the actual emitted photon number to deviate from the known value. We model effects of this deviation on the security of three quantum communication protocols: the Bennett-Brassard 1984 (BB84) quantum key distribution (QKD) protocol without decoy states, Scarani-Acin-Ribordy-Gisin 2004 (SARG04) QKD protocol, and a coin-tossing protocol. For QKD, we model both a strong attack using technology possible in principle, and a realistic attack bounded by today's technology. To maintain the mean photon number in two-way systems, such as plug-and-play and relativistic quantum cryptography schemes, bright pulse energy incoming from the communication channel must be monitored. Implementation of a monitoring detector has largely been ignored so far, except for ID Quantique's commercial QKD system Clavis2. We scrutinize this implementation for security problems, and show that designing a hack-proof pulse-energy-measuring detector is far from trivial. Indeed the first implementation has three serious flaws confirmed experimentally, each of which may be exploited in a cleverly constructed Trojan-horse attack. We discuss requirements for a loophole-free implementation of the monitoring detector.

  12. Statistical Modelling of the Relationship Between Main Development Region Sea Surface Temperature and Atlantic Basin Hurricane Numbers

    E-print Network

    Binter, R; Khare, S; Binter, Roman; Jewson, Stephen; Khare, Shree

    2007-01-01

    We are building a hurricane number prediction scheme that relies, in part, on statistical modelling of the empirical relationship between Atlantic sea surface temperatures and Atlantic basin hurricane numbers. We test out a number of simple statistical models for this relationship, using data from 1900 to 2005 and data from 1950 to 2005, and for both all hurricane numbers and intense hurricane numbers.

  13. Unified position-dependent photon-number quantization in layered structures

    E-print Network

    Mikko Partanen; Teppo Häyrynen; Jani Oksanen; Jukka Tulkki

    2014-12-01

    We have recently developed a position-dependent quantization scheme for describing the ladder and effective photon-number operators associated with the electric field to analyze quantum optical energy transfer in lossy and dispersive dielectrics [Phys. Rev. A, 89, 033831 (2014)]. While having a simple connection to the thermal balance of the system, these operators only described the electric field and its coupling to lossy dielectric bodies. Here we extend this field quantization scheme to include the magnetic field and thus to enable description of the total electromagnetic field and discuss conceptual measurement schemes to verify the predictions. In addition to conveniently describing the formation of thermal balance, the generalized approach allows modeling of the electromagnetic pressure and Casimir forces. We apply the formalism to study the local steady state field temperature distributions and electromagnetic force density in cavities with cavity walls at different temperatures. The calculated local electric and magnetic field temperatures exhibit oscillations that depend on the position as well as the photon energy. However, the effective photon number and field temperature associated with the total electromagnetic field is always position-independent in lossless media. Furthermore, we show that the direction of the electromagnetic force varies as a function of frequency, position, and material thickness.

  14. On the Spectrum of Field Quadratures for a Finite Number of Photons

    E-print Network

    Emilio Pisanty; Eduardo Nahmad-Achar

    2012-09-04

    The spectrum and eigenstates of any field quadrature operator restricted to a finite number $N$ of photons are studied, in terms of the Hermite polynomials. By (naturally) defining \\textit{approximate} eigenstates, which represent highly localized wavefunctions with up to $N$ photons, one can arrive at an appropriate notion of limit for the spectrum of the quadrature as $N$ goes to infinity, in the sense that the limit coincides with the spectrum of the infinite-dimensional quadrature operator. In particular, this notion allows the spectra of truncated phase operators to tend to the complete unit circle, as one would expect. A regular structure for the zeros of the Christoffel-Darboux kernel is also shown.

  15. Probabilistic and statistical relationships between number of vehicles and number of visitors at a geologic site in a National Park

    USGS Publications Warehouse

    Crovelli, R.A.

    1997-01-01

    The National Park Service needs to establish in all of the national parks how large the parking lots should be in order to enjoy and presence our natural resources, for example, in the Delicate Arch in the Arches National Park. Probabilistic and statistical relationships were developed between the number of vehicles (N) at one time in the Wolfe Ranch parking lot and the number of visitors (X) at Delicate Arch 1.5 miles away in the Arches National Park, southeastern Utah. The value of N is determined such that 30 or more visitors are at the arch only 10% of the time.

  16. An accurate simulation model for single-photon avalanche diodes including important statistical effects

    NASA Astrophysics Data System (ADS)

    Qiuyang, He; Yue, Xu; Feifei, Zhao

    2013-10-01

    An accurate and complete circuit simulation model for single-photon avalanche diodes (SPADs) is presented. The derived model is not only able to simulate the static DC and dynamic AC behaviors of an SPAD operating in Geiger-mode, but also can emulate the second breakdown and the forward bias behaviors. In particular, it considers important statistical effects, such as dark-counting and after-pulsing phenomena. The developed model is implemented using the Verilog-A description language and can be directly performed in commercial simulators such as Cadence Spectre. The Spectre simulation results give a very good agreement with the experimental results reported in the open literature. This model shows a high simulation accuracy and very fast simulation rate.

  17. Strong field line shapes and photon statistics from a single molecule under anomalous noise.

    PubMed

    Sanda, Frantisek

    2009-10-01

    We revisit the line-shape theory of a single molecule with anomalous stochastic spectral diffusion. Waiting time profiles for bath induced spectral jumps in the ground and excited states become different when a molecule, probed by continuous-wave laser field, reaches the steady state. This effect is studied for the stationary dichotomic continuous-time-random-walk spectral diffusion of a single two-level chromophore with power-law distributions of waiting times. Correlated waiting time distributions, line shapes, two-point fluorescence correlation function, and Mandel Q parameter are calculated for arbitrary magnitude of laser field. We extended previous weak field results and examined the breakdown of the central limit theorem in photon statistics, indicated by asymptotic power-law growth of Mandel Q parameter. Frequency profile of the Mandel Q parameter identifies the peaks of spectrum, which are related to anomalous spectral diffusion dynamics. PMID:19905298

  18. Time-resolved statistics of non-classical light in Josephson photonics

    E-print Network

    Simon Dambach; Björn Kubala; Vera Gramich; Joachim Ankerhold

    2015-06-19

    The interplay of the tunneling transfer of charges and the emission and absorption of light can be investigated in a setup, where a voltage-biased Josephson junction is connected in series with a microwave cavity. We focus here on the emission processes of photons and analyze the underlying time-dependent statistics using the second-order correlation function $g^{(2)}(\\tau)$ and the waiting-time distribution $w(\\tau)$. Both observables highlight the crossover from a coherent light source to a single-photon source. Due to the nonlinearity of the Josephson junction, tunneling Cooper pairs can create a great variety of non-classical states of light even at weak driving. Analytical results for the weak-driving as well as the classical regime are complemented by a numerical treatment for the full nonlinear case. We also address the question of possible relations between $g^{(2)}(\\tau)$ and $w(\\tau)$ as well as the specific information which is provided by each of them.

  19. A unified statistical framework for material decomposition using multienergy photon counting x-ray detectors

    SciTech Connect

    Choi, Jiyoung; Kang, Dong-Goo; Kang, Sunghoon; Sung, Younghun [Samsung Advanced Institute of Technology (SAIT), San 14, Nong-seo dong, Giheung-gu, Yongin, Kyunggi 446-712 (Korea, Republic of)] [Samsung Advanced Institute of Technology (SAIT), San 14, Nong-seo dong, Giheung-gu, Yongin, Kyunggi 446-712 (Korea, Republic of); Ye, Jong Chul [Bio-Imaging and Signal Processing Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejon 305-701 (Korea, Republic of)] [Bio-Imaging and Signal Processing Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejon 305-701 (Korea, Republic of)

    2013-09-15

    Purpose: Material decomposition using multienergy photon counting x-ray detectors (PCXD) has been an active research area over the past few years. Even with some success, the problem of optimal energy selection and three material decomposition including malignant tissue is still on going research topic, and more systematic studies are required. This paper aims to address this in a unified statistical framework in a mammographic environment.Methods: A unified statistical framework for energy level optimization and decomposition of three materials is proposed. In particular, an energy level optimization algorithm is derived using the theory of the minimum variance unbiased estimator, and an iterative algorithm is proposed for material composition as well as system parameter estimation under the unified statistical estimation framework. To verify the performance of the proposed algorithm, the authors performed simulation studies as well as real experiments using physical breast phantom and ex vivo breast specimen. Quantitative comparisons using various performance measures were conducted, and qualitative performance evaluations for ex vivo breast specimen were also performed by comparing the ground-truth malignant tissue areas identified by radiologists.Results: Both simulation and real experiments confirmed that the optimized energy bins by the proposed method allow better material decomposition quality. Moreover, for the specimen thickness estimation errors up to 2 mm, the proposed method provides good reconstruction results in both simulation and real ex vivo breast phantom experiments compared to existing methods.Conclusions: The proposed statistical framework of PCXD has been successfully applied for the energy optimization and decomposition of three material in a mammographic environment. Experimental results using the physical breast phantom and ex vivo specimen support the practicality of the proposed algorithm.

  20. Solar light trapping in slanted conical-pore photonic crystals: Beyond statistical ray trapping

    NASA Astrophysics Data System (ADS)

    Eyderman, Sergey; John, Sajeev; Deinega, Alexei

    2013-04-01

    We demonstrate that with only 1 ?m, equivalent bulk thickness, of crystalline silicon, sculpted into the form of a slanted conical-pore photonic crystal and placed on a silver back-reflector, it is possible to attain a maximum achievable photocurrent density (MAPD) of 35.5 mA/cm2 from impinging sunlight. This corresponds to absorbing roughly 85% of all available sunlight in the wavelength range of 300-1100 nm and exceeds the limits suggested by previous "statistical ray trapping" arguments. Given the AM 1.5 solar spectrum and the intrinsic absorption characteristics of silicon, the optimum carrier generation occurs for a photonic crystal square lattice constant of 850 nm and slightly overlapping inverted cones with upper (base) radius of 500 nm. This provides a graded refractive index profile with good anti-reflection behavior. Light trapping is enhanced by tilting each inverted cone such that one side of each cone is tangent to the plane defining the side of the elementary cell. When the solar cell is packaged with silica (each pore filled with SiO2), the MAPD in the wavelength range of 400-1100 nm becomes 32.6 mA/cm2 still higher than the Lambertian 4n2 benchmark of 31.2 mA/cm2. In the near infrared regime from 800 to 1100 nm, our structure traps and absorbs light within slow group velocity modes, which propagate nearly parallel to the solar cell interface and exhibit localized high intensity vortex-like flow in the Poynting vector-field. In this near infrared range, our partial MAPD is 10.9 mA/cm2 compared to a partial MAPD of 7 mA/cm2 based on "4n2 statistical ray trapping." These results suggest silicon solar cell efficiencies exceeding 20% with just 1 ?m of silicon.

  1. Statistical Power to Detect the Correct Number of Classes in Latent Profile Analysis.

    PubMed

    Tein, Jenn-Yun; Coxe, Stefany; Cham, Heining

    2013-10-01

    Little research has examined factors influencing statistical power to detect the correct number of latent classes using latent profile analysis (LPA). This simulation study examined power related to inter-class distance between latent classes given true number of classes, sample size, and number of indicators. Seven model selection methods were evaluated. None had adequate power to select the correct number of classes with a small (Cohen's d = .2) or medium (d = .5) degree of separation. With a very large degree of separation (d = 1.5), the Lo-Mendell-Rubin test (LMR), adjusted LMR, bootstrap likelihood-ratio test, BIC, and sample-size adjusted BIC were good at selecting the correct number of classes. However, with a large degree of separation (d = .8), power depended on number of indicators and sample size. The AIC and entropy poorly selected the correct number of classes, regardless of degree of separation, number of indicators, or sample size. PMID:24489457

  2. Quantum Langevin equations for semiconductor light-emitting devices and the photon statistics at a low-injection level

    E-print Network

    Shimizu, Akira

    Quantum Langevin equations for semiconductor light-emitting devices and the photon statistics the microscopic quantum Langevin equations QLEs we derive the effective semiconductor QLEs and the associated into a squeezed state of light 16 . The former mechanism, on the other hand, is often described by the Langevin

  3. Turbulence statistics in fully developed channel flow at low Reynolds number

    NASA Technical Reports Server (NTRS)

    Kim, John; Moin, Parviz; Moser, Robert

    1987-01-01

    A direct numerical simulation of a turbulent channel flow is performed. The unsteady Navier-Stokes equations are solved numerically at a Reynolds number of 3300, based on the mean centerline velocity and channel half-width, with about 4 million grid points. All essential turbulence scales are resolved on the computational grid and no subgrid model is used. A large number of turbulence statistics are computed and compared with the existing experimental data at comparable Reynolds numbers. Agreements as well as discrepancies are discussed in detail. Particular attention is given to the behavior of turbulence correlations near the wall. A number of statistical correlations which are complementary to the existing experimental data are reported for the first time.

  4. Statistical Modelling of the Relationship Between Main Development Region Sea Surface Temperature and \\emph{Landfalling} Atlantic Basin Hurricane Numbers

    E-print Network

    Binter, R; Khare, S; Binter, Roman; Jewson, Stephen; Khare, Shree

    2007-01-01

    We are building a hurricane number prediction scheme that relies, in part, on statistical modelling of the empirical relationship between Atlantic sea surface temperatures and landfalling hurricane numbers. We test out a number of simple statistical models for that relationship, using data from 1900 to 2005 and data from 1950 to 2005, and for both all hurricane numbers and intense hurricane numbers. The results are very different from the corresponding analysis for basin hurricane numbers.

  5. Past quantum state analysis of the photon number evolution in a cavity

    E-print Network

    Théo Rybarczyk; Stefan Gerlich; Bruno Peaudecerf; Mariane Penasa; Brian Julsgaard; Klaus Moelmer; Sébastien Gleyzes; Michel Brune; Jean-Michel Raimond; Serge Haroche; Igor Dotsenko

    2014-09-03

    A quantum system can be monitored through repeated interactions with meters, followed by their detection. The state of the system at time t is thus conditioned on the information obtained until that time. More insight in the state dynamics is provided, however, by the past quantum state (PQS) [S. Gammelmark et al. Phys. Rev. Lett. 111, 160401 (2013)]. It relies on all aspects of the system evolution which are recorded in the past and in the future of t. Using PQS analysis for the quantum non-demolition photon number counting in a cavity, we can reveal information hidden in the standard approach and resolve a wider range of number states. This experiment demonstrates the strong potential of PQS analysis.

  6. Using cavitation to measure statistics of low-pressure events in large-Reynolds-number turbulence

    E-print Network

    La Porta, Arthur

    Using cavitation to measure statistics of low-pressure events in large-Reynolds-number turbulence A is studied using cavitation. The flow is seeded with microscopic gas bubbles and the hydrostatic pressure is reduced until large negative pressure fluctuations trigger cavitation. Cavitation is detected via light

  7. Atmospheric particle number size distribution in central Europe: Statistical relations to air masses and meteorology

    Microsoft Academic Search

    Wolfram Birmili; Alfred Wiedensohler; Jost Heintzenberg; Katrin Lehmann

    2001-01-01

    Atmospheric particle number size distributions determined over 1.5 years at a central European site were statistically analyzed in terms of their relation to time of day, season, meteorology, and synoptic-scale air masses. All size distributions were decomposed into lognormal particle modes corresponding to the accumulation, Aitken, aged nucleation, and nucleation modes. The concentration of nucleation mode particles (30 nm) lacked

  8. Photon statistics of radiation scattered by relativistic electrons in an interfering electromagnetic field

    NASA Astrophysics Data System (ADS)

    Bertolotti, M.; Sibilia, C.; Perina, J.; Perinova, V.

    1984-09-01

    The statistical properties of backscattered radiation in the electron rest frame are studied when the radiation system is coupled to a 'reservoir' (electron beam). Anticorrelation effects are found to occur between scattered modes; super-Poissonian statistics also occurs in each emitted mode when the short-time approximation is adopted. In the radiation field, two incident modes at nearly the same frequency and two backscattered modes at nearly equal frequency are considered. The coherent state technique and the q-c number correspondence are employed, working in the Schroedinger picture with the generalized Fokker-Plack equation for the antinormal quasi-distribution function. The factorial moments are derived from the solution of that equation.

  9. Statistical properties of online avatar numbers in a massive multiplayer online role-playing game

    NASA Astrophysics Data System (ADS)

    Jiang, Zhi-Qiang; Ren, Fei; Gu, Gao-Feng; Tan, Qun-Zhao; Zhou, Wei-Xing

    2010-02-01

    Massive multiplayer online role-playing games (MMORPGs) have been very popular in the past few years. The profit of an MMORPG company is proportional to how many users registered, and the instant number of online avatars is a key factor to assess how popular an MMORPG is. We use the online-offline logs on an MMORPG server to reconstruct the instant number of online avatars per second and investigate its statistical properties. We find that the online avatar number exhibits one-day periodic behavior and clear intraday pattern, the fluctuation distribution of the online avatar numbers has a leptokurtic non-Gaussian shape with power-law tails, and the increments of online avatar numbers after removing the intraday pattern are uncorrelated and the associated absolute values have long-term correlation. In addition, both time series exhibit multifractal nature.

  10. Development of a Statistical Model for Seasonal Prediction of North Atlantic Hurricane Numbers

    NASA Astrophysics Data System (ADS)

    Davis, K.; Zeng, X.

    2014-12-01

    Tropical cyclones cause more financial distress to insurance companies than any other natural disaster. From 1970-2002, it is estimated that hurricanes caused 44 billion dollars in damage, greater than 2.5 times the the next costliest catastrophe. Theses damages do not go without effect. A string of major catastrophes from 1991-1994 caused nine property firms to bankrupt and caused serious financial strain on others. The public was not only affected by the loss of life and property, but the increase in tax dollars for disaster relief. Providing better seasonal predictions of North Atlantic hurricane activity farther in advance will help alleviate some of the financial strains these major catastrophes put on the nation. A statistical model was first developed by Bill Gray's team to predict the total number of hurricanes over the North Atlantic in 1984, followed by other statistical methods, dynamic modeling, and hybrid methods in recent years. However, all these methods showed little to no skill with forecasts made by June 1 in recent years. In contrast to the relatively small year-to-year change in seasonal hurricane numbers pre-1980, there has been much greater interannual changes since, especially since the year 2000. For instance, while there were very high hurricane numbers in 2005 and 2010, 2013 was one of the lowest in history. Recognizing these interdecadal changes in the dispersion of hurricane numbers, we have developed a new statistical model to more realistically predict (by June 1 each year) the seasonal hurricane number over the North Atlantic. It is based on the Multivariate ENSO Index (MEI) conditioned by the Atlantic Multidecadal Oscillation (AMO) index, the zonal wind stress and sea surface temperature over the Atlantic. It provides both the deterministic number and the range of hurricane numbers. The details of the model and its performance from 1950-2014 in comparison with other methods will be presented in our presentation.

  11. Wideband direction finding using a photonic robust symmetrical number system technique

    NASA Astrophysics Data System (ADS)

    Tedesso, Thomas W.; Calusdian, James; Sewing, Carsten; Pace, Phillip E.

    2014-11-01

    Dual electrode Mach-Zehnder modulators (DE-MZMs) are used to conduct phase detection for direct wideband direction finding (DF) of microwave signals. It is demonstrated theoretically and through simulation and experimentation that the normalized magnitude of the output signal phase detector circuit is equal to |sin(?/2)|, where ? is the phase difference between the plane waves arriving at the reference and measurement antennas of a linear DF array. A four-element wideband photonic DF system with robust symmetrical number system preprocessing is presented. Simulation and experimental testing results are provided to demonstrate the theoretical concept. The results demonstrate a direct DF receiver using DE-MZMs that achieves fine angular resolution using a much smaller array size than is typically required for linear arrays employing super-resolution signal processing techniques.

  12. Quadrature entanglement and photon-number correlations accompanied by phase-locking

    SciTech Connect

    Adamyan, H. H.; Manvelyan, S. B. [Institute for Physical Research, National Academy of Sciences, Ashtarak-2, 378410 (Armenia); Adamyan, N. H. [Yerevan State University, A. Manookyan 1, 375049, Yerevan (Armenia); Kryuchkyan, G. Yu. [Yerevan State University, A. Manookyan 1, 375049, Yerevan (Armenia); Institute for Physical Research, National Academy of Sciences, Ashtarak-2, 378410 (Armenia)

    2006-03-15

    We investigate quantum properties of phase-locked light beams generated in a nondegenerate optical parametric oscillator (NOPO) with an intracavity waveplate. This investigation continues our previous analysis presented in Phys. Rev. A 69, 053814 (2004), and involves problems of continuous-variable quadrature entanglement in the spectral domain, photon-number correlations as well as the signatures of phase-locking in the Wigner function. We study the role of phase-localizing processes on the quantum correlation effects. The peculiarities of phase-locked NOPO in the self-pulsing instability operational regime are also cleared up. The results are obtained in the P-representation as a quantum-mechanical calculation in the framework of stochastic equations of motion, as well as by numerical simulation based on the method of quantum state diffusion.

  13. Generating arbitrary photon-number entangled states for continuous-variable quantum informatics

    E-print Network

    Su-Yong Lee; Jiyong Park; Hai-Woong Lee; Hyunchul Nha

    2012-06-13

    We propose two experimental schemes that can produce an arbitrary photon-number entangled state (PNES) in a finite dimension. This class of entangled states naturally includes non-Gaussian continuous-variable (CV) states that may provide some practical advantages over the Gaussian counterparts (two-mode squeezed states). We particularly compare the entanglement characteristics of the Gaussian and the non-Gaussian states in view of the degree of entanglement and the Einstein-Podolsky-Rosen correlation, and further discuss their applications to the CV teleportation and the nonlocality test. The experimental imperfection due to the on-off photodetectors with nonideal efficiency is also considered in our analysis to show the feasibility of our schemes within existing technologies.

  14. Photon-number splitting of squeezed light by a single qubit in circuit QED

    NASA Astrophysics Data System (ADS)

    Moon, Kyungsun

    2013-10-01

    We theoretically propose an efficient way to generate and detect squeezed light by a single qubit in circuit QED. By tuning the qubit energy splitting close to the fundamental frequency of the first harmonic mode (FHM) in a transmission line resonator and placing the qubit at the nodal point of the third harmonic mode, one can generate the resonantly enhanced squeezing of the FHM upon pumping with the second harmonic mode. In order to investigate the photon number splitting for the squeezed FHM, we have numerically calculated the qubit absorption spectrum, which exhibits regularly spaced peaks at frequencies separated by twice the effective dispersive shift. It is also shown that adding a small pump field for the FHM makes additional peaks develop in between the dominant ones as well.

  15. Field-quadrature and photon-number correlations produced by parametric processes.

    PubMed

    McKinstrie, C J; Karlsson, M; Tong, Z

    2010-09-13

    In a previous paper [Opt. Express 13, 4986 (2005)], formulas were derived for the field-quadrature and photon-number variances produced by multiple-mode parametric processes. In this paper, formulas are derived for the quadrature and number correlations. The number formulas are used to analyze the properties of basic devices, such as two-mode amplifiers, attenuators and frequency convertors, and composite systems made from these devices, such as cascaded parametric amplifiers and communication links. Amplifiers generate idlers that are correlated with the amplified signals, or correlate pre-existing pairs of modes, whereas attenuators decorrelate pre-existing modes. Both types of device modify the signal-to-noise ratios (SNRs) of the modes on which they act. Amplifiers decrease or increase the mode SNRs, depending on whether they are operated in phase-insensitive (PI) or phase-sensitive (PS) manners, respectively, whereas attenuators always decrease these SNRs. Two-mode PS links are sequences of transmission fibers (attenuators) followed by two-mode PS amplifiers. Not only do these PS links have noise figures that are 6-dB lower than those of the corresponding PI links, they also produce idlers that are (almost) completely correlated with the signals. By detecting the signals and idlers, one can eliminate the effects of electronic noise in the detectors. PMID:20940873

  16. Dependence of transmission on number of rows of 2D macroporous silicon photonic band gap material

    Microsoft Academic Search

    S. W. Leonard; K. Busch; S. John; H. M. van Driel; A. Birner; U. Gosele

    1999-01-01

    Although it is well known that photonic band gap (PBG) materials can provide a high degree of attenuation within the photonic band gap, relatively little work has been done on visible or near-infrared gap materials to investigate exactly how this attenuation depends on the material thickness. This is an important issue because it is the attenuating property of photonic band

  17. Light statistics by non-calibrated linear photodetectors

    E-print Network

    Maria Bondani; Alessia Allevi; Alessandra Andreoni

    2008-10-22

    We theoretically demonstrate that detectors endowed with internal gain and operated in regimes in which they do not necessarily behave as photon-counters, but still ensure linear input/output responses, can allow a self-consistent characterization of the statistics of the number of detected photons without need of knowing their gain. We present experiments performed with a photo-emissive hybrid detector on a number of classical fields endowed with non-trivial statistics and show that the method works for both microscopic and mesoscopic photon numbers. The obtained detected-photon probability distributions agree with those expected for the photon numbers, which are also reconstructed by an independent method.

  18. Quantum theory of light scattering in a one-dimensional channel: Interaction effect on photon statistics and entanglement entropy

    NASA Astrophysics Data System (ADS)

    Pletyukhov, Mikhail; Gritsev, Vladimir

    2015-06-01

    We provide a complete and exact quantum description of coherent light scattering in a one-dimensional multimode transmission line coupled to a two-level emitter. Using a recently developed scattering approach, we discuss transmission properties, the power spectrum, the full counting statistics, and the entanglement entropy of transmitted and reflected states of light. Our approach takes into account spatial parameters of an incident coherent pulse as well as waiting and counting times of a detector. We describe the time evolution of the power spectrum and observe deviations from the Poissonian statistics for reflected and transmitted fields. In particular, the statistics of reflected photons can change from sub-Poissonian to super-Poissonian for increasing values of the detuning, while the statistics of transmitted photons is strictly super-Poissonian in all parametric regimes. We study the entanglement entropy of some spatial part of the scattered pulse and observe that it obeys the area laws and that it is bounded by the maximal entropy of the effective four-level system.

  19. Reynolds number dependency of near-wall statistics of zero-pressure-gradient turbulent boundary layer

    NASA Astrophysics Data System (ADS)

    Buschmann, M. H.; Keirsbulck, L.; Fourrié, G.; Labraga, L.; Gad-el-Hak, M.

    2011-12-01

    We report high-resolution LDA and HWA measurements of the streamwise velocity component of a flat-plate turbulent boundary layer (ZPG TBL) over a range of momentum thickness Reynolds number from 1,170 to 3,720. The primary objective of this work is to investigate the near-wall behavior and the scaling of high-order statistics. In particular, we are interested in certain Kármán number dependencies. The obtained data are in excellent agreement with most recent DNS-results, which allows direct comparison of detailed results such as peak value and position of streamwise stress, wall-values of skewness and flatness factors, and turbulence dissipation rate. The experimental data clearly reveal the failure of classical scaling. An alternative mixed scaling based on u?3/2ue1/2 removes these discrepancies.

  20. Dependence of transmission on number of rows of 2-D macroporous silicon photonic band gap material

    Microsoft Academic Search

    S. W. Leonard; K. Busch; S. John; H. M. van Driel; A. Birner; U. Gosele

    1999-01-01

    Summary form only given. Although it is well known that photonic band gap (PBG) materials can provide a high degree of attenuation within the photonic band gap, relatively little work has been done on visible or near-infrared gap materials to investigate exactly how this attenuation depends on the material thickness. This is an important issue because it is the attenuating

  1. SPECIAL ISSUE DEVOTED TO MULTIPLE RADIATION SCATTERING IN RANDOM MEDIA: Time-domain diffuse optical tomography using analytic statistical characteristics of photon trajectories

    NASA Astrophysics Data System (ADS)

    Konovalov, Aleksandr B.; Vlasov, V. V.; Kalintsev, A. G.; Kravtsenyuk, Olga V.; Lyubimov, Vladimir V.

    2006-11-01

    The inverse problem of diffuse optical tomography (DOT) is reduced by the method of photon average trajectories (PAT) to the solution of the integral equation integrated along the conditional mean statistical photon trajectory. The PAT bending near the flat boundary of a scattering medium is estimated analytically. These estimates are used to determine the analytic statistical characteristics of photon trajectories for the flat layer geometry. The inverse DOT problem is solved by using the multiplicative algebraic algorithm modified to improve the convergence of the iteration reconstruction process. The numerical experiment shows that the modified PAT method permits the reconstruction of near-surface optical inhomogeneities virtually without distortions.

  2. Table l.-Numbers offish cau9ht and retained, by species (in thousands). 'Numbers caught and retained are not considered to be statistically reliable.

    E-print Network

    Table l.-Numbers offish cau9ht and retained, by species (in thousands). 'Numbers caught and retained are not considered to be statistically reliable. 2AlIhough retention of over 18 million rainbow is such that a relative comparison. for purposes of this table. is not meaningful. Canadian Survey Shows Sportfishing

  3. Quantum plasmonics with quantum dot-metal nanoparticle molecules: influence of the Fano effect on photon statistics.

    PubMed

    Ridolfo, A; Di Stefano, O; Fina, N; Saija, R; Savasta, S

    2010-12-31

    We study theoretically the quantum optical properties of hybrid molecules composed of an individual quantum dot and a metallic nanoparticle. We calculate the resonance fluorescence of this composite system. Its incoherent part, arising from nonlinear quantum processes, is enhanced by more than 2 orders of magnitude as compared to that of the dot alone. The coupling between the two systems gives rise to a Fano interference effect which strongly influences the quantum statistical properties of the scattered photons: a small frequency shift of the incident light field may cause changes in the intensity correlation function of the scattered field of orders of magnitude. The system opens a good perspective for applications in active metamaterials and ultracompact single-photon devices. PMID:21231659

  4. Role of Initial Entanglement and Non-Gaussianity in the Decoherence of Photon-Number Entangled States Evolving in a Noisy Channel

    E-print Network

    Paris, Matteo G. A.

    in the number of photons: photon-number entangled states (PNES). The latter have Schmidt decomposition communication schemes involving PNES have been proposed [11]. Furthermore, the set of PNES contains mostly non-Gaussian states. Finally, PNES are good candidates for long-distance quantum communication, because they have been

  5. Photon-photon collisions

    SciTech Connect

    Burke, D.L.

    1982-10-01

    Studies of photon-photon collisions are reviewed with particular emphasis on new results reported to this conference. These include results on light meson spectroscopy and deep inelastic e..gamma.. scattering. Considerable work has now been accumulated on resonance production by ..gamma gamma.. collisions. Preliminary high statistics studies of the photon structure function F/sub 2//sup ..gamma../(x,Q/sup 2/) are given and comments are made on the problems that remain to be solved.

  6. Discovery and statistical genotyping of copy-number variation from whole-exome sequencing depth.

    PubMed

    Fromer, Menachem; Moran, Jennifer L; Chambert, Kimberly; Banks, Eric; Bergen, Sarah E; Ruderfer, Douglas M; Handsaker, Robert E; McCarroll, Steven A; O'Donovan, Michael C; Owen, Michael J; Kirov, George; Sullivan, Patrick F; Hultman, Christina M; Sklar, Pamela; Purcell, Shaun M

    2012-10-01

    Sequencing of gene-coding regions (the exome) is increasingly used for studying human disease, for which copy-number variants (CNVs) are a critical genetic component. However, detecting copy number from exome sequencing is challenging because of the noncontiguous nature of the captured exons. This is compounded by the complex relationship between read depth and copy number; this results from biases in targeted genomic hybridization, sequence factors such as GC content, and batching of samples during collection and sequencing. We present a statistical tool (exome hidden Markov model [XHMM]) that uses principal-component analysis (PCA) to normalize exome read depth and a hidden Markov model (HMM) to discover exon-resolution CNV and genotype variation across samples. We evaluate performance on 90 schizophrenia trios and 1,017 case-control samples. XHMM detects a median of two rare (<1%) CNVs per individual (one deletion and one duplication) and has 79% sensitivity to similarly rare CNVs overlapping three or more exons discovered with microarrays. With sensitivity similar to state-of-the-art methods, XHMM achieves higher specificity by assigning quality metrics to the CNV calls to filter out bad ones, as well as to statistically genotype the discovered CNV in all individuals, yielding a trio call set with Mendelian-inheritance properties highly consistent with expectation. We also show that XHMM breakpoint quality scores enable researchers to explicitly search for novel classes of structural variation. For example, we apply XHMM to extract those CNVs that are highly likely to disrupt (delete or duplicate) only a portion of a gene. PMID:23040492

  7. Coherence holography and photon-correlation holography: marriage between holography and statistical optics

    NASA Astrophysics Data System (ADS)

    Takeda, Mitsuo; Wang, Wei; Naik, Dinesh N.

    2011-10-01

    We review two techniques of unconventional holography, coherence holography and photon-correlation holography, which we recently proposed and experimentally demonstrated. We will emphasize the importance of noticing mathematical analogies in optics and physical phenomena, which give insights into the methodology for developing new techniques.

  8. Single-photon detection by rod cells of the retina

    Microsoft Academic Search

    F. Rieke; D. A. Baylor

    1998-01-01

    At low light levels, the visual system detects and counts photon absorptions with a reliability close to limits set by statistical fluctuations in the number of absorbed photons. Thus the rod photoreceptors that provide the input signals to the dark-adapted visual system act as nearly perfect photon counters. This elegant performance is possible because light detection in the rods satisfies

  9. Higher-order photon correlations in pulsed photonic crystal nanolasers

    SciTech Connect

    Elvira, D.; Hachair, X.; Braive, R.; Beaudoin, G.; Robert-Philip, I.; Sagnes, I.; Abram, I.; Beveratos, A. [Laboratoire de Photonique et Nanostructures LPN-CNRS UPR20, Route de Nozay, F-91460 Marcoussis (France); Verma, V. B.; Baek, B.; Nam, S. W.; Stevens, M. J. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States); Dauler, E. A. [Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420 (United States)

    2011-12-15

    We report on the higher-order photon correlations of a high-{beta} nanolaser under pulsed excitation at room temperature. Using a multiplexed four-element superconducting single-photon detector we measured g{sup (n)}(0-vector) with n=2,3,4. All orders of correlation display partially chaotic statistics, even at four times the threshold excitation power. We show that this departure from coherence and Poisson statistics is due to the quantum fluctuations associated with the small number of photons at the lasing threshold.

  10. Dual adaptive statistical approach for quantitative noise reduction in photon-counting medical imaging: application to nuclear medicine images.

    PubMed

    Hannequin, Pascal Paul

    2015-06-01

    Noise reduction in photon-counting images remains challenging, especially at low count levels. We have developed an original procedure which associates two complementary filters using a Wiener-derived approach. This approach combines two statistically adaptive filters into a dual-weighted (DW) filter. The first one, a statistically weighted adaptive (SWA) filter, replaces the central pixel of a sliding window with a statistically weighted sum of its neighbors. The second one, a statistical and heuristic noise extraction (extended) (SHINE-Ext) filter, performs a discrete cosine transformation (DCT) using sliding blocks. Each block is reconstructed using its significant components which are selected using tests derived from multiple linear regression (MLR). The two filters are weighted according to Wiener theory. This approach has been validated using a numerical phantom and a real planar Jaszczak phantom. It has also been illustrated using planar bone scintigraphy and myocardial single-photon emission computed tomography (SPECT) data. Performances of filters have been tested using mean normalized absolute error (MNAE) between the filtered images and the reference noiseless or high-count images.Results show that the proposed filters quantitatively decrease the MNAE in the images and then increase the signal-to-noise Ratio (SNR). This allows one to work with lower count images. The SHINE-Ext filter is well suited to high-size images and low-variance areas. DW filtering is efficient for low-size images and in high-variance areas. The relative proportion of eliminated noise generally decreases when count level increases. In practice, SHINE filtering alone is recommended when pixel spacing is less than one-quarter of the effective resolution of the system and/or the size of the objects of interest. It can also be used when the practical interest of high frequencies is low. In any case, DW filtering will be preferable.The proposed filters have been applied to nuclear medicine images but can also be used for any other kind of photon-counting images, such as x-ray and fluorescence images. PMID:26009552

  11. Dual adaptive statistical approach for quantitative noise reduction in photon-counting medical imaging: application to nuclear medicine images

    NASA Astrophysics Data System (ADS)

    Hannequin, Pascal Paul

    2015-06-01

    Noise reduction in photon-counting images remains challenging, especially at low count levels. We have developed an original procedure which associates two complementary filters using a Wiener-derived approach. This approach combines two statistically adaptive filters into a dual-weighted (DW) filter. The first one, a statistically weighted adaptive (SWA) filter, replaces the central pixel of a sliding window with a statistically weighted sum of its neighbors. The second one, a statistical and heuristic noise extraction (extended) (SHINE-Ext) filter, performs a discrete cosine transformation (DCT) using sliding blocks. Each block is reconstructed using its significant components which are selected using tests derived from multiple linear regression (MLR). The two filters are weighted according to Wiener theory. This approach has been validated using a numerical phantom and a real planar Jaszczak phantom. It has also been illustrated using planar bone scintigraphy and myocardial single-photon emission computed tomography (SPECT) data. Performances of filters have been tested using mean normalized absolute error (MNAE) between the filtered images and the reference noiseless or high-count images. Results show that the proposed filters quantitatively decrease the MNAE in the images and then increase the signal-to-noise Ratio (SNR). This allows one to work with lower count images. The SHINE-Ext filter is well suited to high-size images and low-variance areas. DW filtering is efficient for low-size images and in high-variance areas. The relative proportion of eliminated noise generally decreases when count level increases. In practice, SHINE filtering alone is recommended when pixel spacing is less than one-quarter of the effective resolution of the system and/or the size of the objects of interest. It can also be used when the practical interest of high frequencies is low. In any case, DW filtering will be preferable. The proposed filters have been applied to nuclear medicine images but can also be used for any other kind of photon-counting images, such as x-ray and fluorescence images.

  12. A Supplement to "The Number of Guttman Errors as a Simple and Powerful Person-Fit Statistic."

    ERIC Educational Resources Information Center

    Meijer, Rob R.

    1995-01-01

    A statistic used by R. Meijer (1994) to determine person-fit referred to the number of errors from the deterministic Guttman model (L. Guttman, 1950), but this was, in fact, based on the number of errors from the deterministic Guttman model as defined by J. Loevinger (1947, 1948). (SLD)

  13. Optimum values of air-filling fraction for photonic crystal fibers with different configurations and fixed number of air rings.

    PubMed

    Zendehnam, Akbar; Hosseinpour, Maryam; Mirzaei, Mahmood; Hedayati, Kambiz

    2014-02-20

    In this study, a Gaussian amp function related to the Gaussian family is employed to approximate the output intensity profile of various arrangements of air holes in photonic crystal fibers (PCFs) with a fixed number of air rings (N=4). It is shown that d/?=0.5 can be the best minimum value of air-filling fraction for all of the studied PCFs when ?=1.35???m, whereas, for ?=1.55 and 1.65 ?m, d/?=0.6 is suitable for achieving the maximum output intensity with very low confinement loss. PMID:24663304

  14. High-statistics study of neutral-pion pair production in two-photon collisions

    SciTech Connect

    Uehara, S.; Haba, J.; Hazumi, M.; Iwasaki, Y.; Katayama, N.; Kichimi, H.; Krokovny, P.; Nakao, M.; Nishida, S.; Sakai, Y.; Tanaka, M.; Uno, S. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Watanabe, Y.; Okuno, S. [Kanagawa University, Yokohama (Japan); Nakazawa, H.; Chen, A. [National Central University, Chung-li (China); Aihara, H. [Department of Physics, University of Tokyo, Tokyo (Japan); Arinstein, K.; Aulchenko, V.; Bondar, A. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation)] (and others)

    2009-03-01

    The differential cross sections for the process {gamma}{gamma}{yields}{pi}{sup 0}{pi}{sup 0} have been measured in the kinematic range 0.6 GeVphoton production of two pions in the G wave. In the higher-energy region, we observe production of the {chi}{sub c0} charmonium state and obtain the product of its two-photon decay width and branching fraction to {pi}{sup 0}{pi}{sup 0}. We also compare the observed angular dependence and ratios of cross sections for neutral-pion and charged-pion pair production to QCD models. The energy and angular dependence above 3.1 GeV are compatible with those measured in the {pi}{sup +}{pi}{sup -} channel, and in addition we find that the cross section ratio, {sigma}({pi}{sup 0}{pi}{sup 0})/{sigma}({pi}{sup +}{pi}{sup -}), is 0.32{+-}0.03{+-}0.05 on average in the 3.1-4.1 GeV region.

  15. Case Study Applications of Statistics in Institutional Research. Resources in Institutional Research, Number Ten.

    ERIC Educational Resources Information Center

    Coughlin, Mary Ann; Pagano, Marian

    This monograph covers the theory, application, and interpretation of both descriptive and inferential statistical techniques in institutional research. Each chapter opens with a hypothetical case study, which is used to illustrate the application of one or more statistical procedures to typical research questions. Chapter 2 covers the comparison…

  16. Reversing the weak measurement of an arbitrary field with finite photon number 

    E-print Network

    Sun, Qingqing; Al-Amri, M.; Zubairy, M. Suhail.

    2009-01-01

    ,m=0nmax #1;nme?#1;n+m#2;#2;t#6;n#7;#8;m#6; according to the quantum trajectory theory, where 2#2; is the photon decay rate in the cavity and t is the duration of the measurement. Here we ignore all the normalization con- stants for simplicity until... the end of the derivation. For finite time this measurement is not sharp since any Fock compo- nent could give null result. To reverse the weak measure- ment, we need to swap the components symmetrically to #5;n,m=0nmax #1;nme?#1;n+m#2;#2;t#6;N?n#7...

  17. Direct Observation of Sub-Poissonian Number Statistics in a Degenerate Bose Gas

    NASA Astrophysics Data System (ADS)

    Chuu, C.-S.; Schreck, F.; Meyrath, T. P.; Hanssen, J. L.; Price, G. N.; Raizen, M. G.

    2005-12-01

    We report the direct observation of sub-Poissonian number fluctuation for a degenerate Bose gas confined in an optical trap. Reduction of number fluctuations below the Poissonian limit is observed for average numbers that range from 300 to 60 atoms.

  18. High-statistics measurement of neutral-pion pair production in two-photon collisions

    SciTech Connect

    Uehara, S.; Adachi, I.; Dalseno, J.; Haba, J.; Itoh, R.; Iwasaki, Y.; Katayama, N.; Kichimi, H.; Krokovny, P.; Nakamura, I.; Nakao, M.; Nishida, S.; Ozaki, H.; Sakai, Y.; Suzuki, S. Y.; Uno, S. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Watanabe, Y.; Okuno, S. [Kanagawa University, Yokohama (Japan); Aihara, H.; Iwasaki, M. [Department of Physics, University of Tokyo, Tokyo (Japan)] (and others)

    2008-09-01

    We present a high-statistics measurement of differential cross sections and the total cross section for the process {gamma}{gamma}{yields}{pi}{sup 0}{pi}{sup 0} in the kinematic range 0.6 GeV{<=}W{<=}4.0 GeV and |cos{theta}*|{<=}0.8, where W and {theta}* are the energy and pion scattering angle, respectively, in the {gamma}{gamma} center-of-mass system. Differential cross sections are fitted to obtain information on S, D{sub 0}, D{sub 2}, G{sub 0}, and G{sub 2} waves. The G waves are important above W{approx_equal}1.6 GeV. The general behavior of partial waves is studied by fitting differential cross sections in a simple parametrization where amplitudes contain resonant contributions and smooth background. The D{sub 2} wave is dominated by the f{sub 2}(1270) meson whose parameters are consistent with the current world averages. The D{sub 0} wave contains a f{sub 2}(1270) component, whose fraction is fitted. For the S wave, the f{sub 0}(980) parameters are found to be consistent with the values determined from our recent {pi}{sup +}{pi}{sup -} data. In addition to the f{sub 0}(980), the S wave prefers to have another resonance-like contribution whose parameters are obtained.

  19. Equipartitions and a distribution for numbers: A statistical model for Benford's law

    NASA Astrophysics Data System (ADS)

    Iafrate, Joseph R.; Miller, Steven J.; Strauch, Frederick W.

    2015-06-01

    A statistical model for the fragmentation of a conserved quantity is analyzed, using the principle of maximum entropy and the theory of partitions. Upper and lower bounds for the restricted partitioning problem are derived and applied to the distribution of fragments. The resulting power law directly leads to Benford's law for the first digits of the parts.

  20. Need for Assistance in the Activities of Daily Living. Disability Statistics Abstract, Number 18.

    ERIC Educational Resources Information Center

    Kennedy, Jae; LaPlante, Mitchell P.; Kaye, H. Stephen

    This abstract summarizes recent statistics on those needing assistance in Activities of Daily Living (ADLs), along with participation rates for various proposed benefit programs, based on an analysis of the 1990-91 Survey of Income and Program Participation. Analysis indicates: (1) an estimated 1.9 percent of the population has difficulty…

  1. Who Pays for the Medical Care of People with Disabilities? Disability Statistics Abstract, Number 13.

    ERIC Educational Resources Information Center

    Trupin, Laura; Rice, Dorothy P.; Max, Wendy

    This statistical abstract presents data on the sources of payment for medical care for people with disabilities in different age groups. All estimates come from the National Medical Expenditures Survey, a nationally representative survey of the civilian non-institutionalized population of the U.S. conducted in 1987. Six categories of payment…

  2. Grant Title: METHODOLOGY, MEASUREMENT, AND STATISTICS Funding Opportunity Number: NSF 12-510.

    E-print Network

    Farritor, Shane

    , Behavioral, and Economic Sciences that supports the development of innovative analytical and statistical-510. Agency/Department: National Science Foundation; Directorate for Social, Behavioral & Economic Sciences in theory, and have potential utility for multiple fields within the social and behavioral sciences. As part

  3. Static Numbers to Dynamic Statistics: Designing a Policy-Friendly Social Policy Indicator Framework

    ERIC Educational Resources Information Center

    Ahn, Sang-Hoon; Choi, Young Jun; Kim, Young-Mi

    2012-01-01

    In line with the economic crisis and rapid socio-demographic changes, the interest in "social" and "well-being" indicators has been revived. Social indicator movements of the 1960s resulted in the establishment of social indicator statistical frameworks; that legacy has remained intact in many national governments and international organisations.…

  4. Manufacturing Numbers: How Inaccurate Statistics Conceal U.S. Industrial Decline.

    ERIC Educational Resources Information Center

    Mishel, Lawrence

    Contrary to a major statistical series calculated by the U.S. Bureau of Economic Analysis, the Gross Product Originating (GPO) series, the United States has experienced a definite erosion of its industrial base between 1973 and 1985, with manufacturing dropping at least 2.8 percent and perhaps as much as 4.5 percent in its share of national…

  5. Estimating the number of clusters in a dataset via the Gap statistic

    Microsoft Academic Search

    Robert Tibshirani; Guenther Walther; Trevor Hastie

    2000-01-01

    We propose a method (the \\\\Gap statistic") for estimating the numberof clusters (groups) in a set of data. The technique uses the outputof any clustering algorithm (e.g. k-means or hierarchical), comparingthe change in within cluster dispersion to that expected under an appropriatereference null distribution. Some theory is developed forthe proposal and a simulation study that shows that the Gap statisticusually

  6. On the Poisson Approximation to Photon Distribution for Faint Lasers Yucheng Hua

    E-print Network

    Lu, Tiao

    On the Poisson Approximation to Photon Distribution for Faint Lasers Yucheng Hua , Xiang Pengb statistics for attenuated faint laser pulses is quantitatively studied. It confirms that, even for a non-Poissonian laser source, after being attenuated into faint laser with ultra-low mean photon number, the photon

  7. Detection of VUV photons with large-area avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Monteiro, C. M. B.; Fernandes, L. M. P.; Lopes, J. A. M.; Veloso, J. F. C. A.; Santos, J. M. F. Dos

    2005-08-01

    The room-temperature response of large-area avalanche photodiodes (LAAPDs) to 128- and 172-nm light pulses is investigated. The minimum detectable number of photons, which can produce a signal just above the noise level, is found to be around 1300 and 600 photons, respectively. The LAAPD relative statistical fluctuations in the detection of 15 000 photons of 128 nm and 25 500 photons of 172 nm were found to be about 3.9% and 2.2%, respectively. Both the minimum detectable number of photons and statistical fluctuations do not depend on the photon wavelength, but rather on the number of charge carriers produced by the light pulse in the LAAPD. For these light levels, good LAAPD performance is already achieved for gains as low as 30 to 60.

  8. A statistical method to detect chromosomal regions with DNA copy number alterations using SNP-array-based CGH data

    Microsoft Academic Search

    Yinglei Lai; Hongyu Zhao

    Single nucleotide polymorphism (SNP) arrays were used to detect chromosomal regions with DNA copy number alterations. Current statistical methods for microarray-based comparative genomic hybridization (array-CGH) analysis generally assume certain relationships among adjacent markers on the same chromosome, and these assumptions may be questionable. For an SNP-array-based CGH study, multiple normal reference SNP arrays were collected. In order to utilize these

  9. Statistical classification and purposeful projection of observations into a space of dimensionality no more than the number of classes

    Microsoft Academic Search

    E. E. Zhuk

    2008-01-01

    Consideration was given to the reduction of dimensionality in the problems of statistical classification. For the case where\\u000a the observations from different classes have the same covariance matrix, the method of purposeful projection was used to transform\\u000a the initial space of attributes into a space of dimensionality no more than the number of classes which do not modify the\\u000a Mahalanobis

  10. Numbers

    NSDL National Science Digital Library

    2013-06-14

    The purpose of this video tutorial is to review a couple ways in which we think about numbers. Thinking in terms of street numbers, money in bank accounts, and quantum particles (e.g. Bose-Einstein condensate) is contrasted with focusing on associating numbers with distinguishable manipulatives, as is more familiar in K-8 courses. This video concludes with a reminder that the symbol "infinity" is not, itself, a number.

  11. Numbers

    NSDL National Science Digital Library

    Jo Edkins

    2006-01-01

    This engaging web site contains information and interactive applets related to various number systems: Egyptian, Babylonian, Chinese, Greek, Roman, Mayan, and Arabic. Users learn the history and structure of each system as well as how to count and write numbers. The site also allows users to explore finger systems, calculating machines, other number bases, and "interesting numbers." A series of pages on data and graphs includes information and activities on gathering, analyzing, graphing and sorting data. (Because the section on the Arabic number system is so extensive, it is cataloged separately as a related resource.)

  12. Statistical estimations of the number of future ozone exceedances due to climate change in Europe

    NASA Astrophysics Data System (ADS)

    Varotsos, K. V.; Tombrou, M.; Giannakopoulos, C.

    2013-06-01

    A statistical model to examine the potential impact of increasing future temperatures due to climate change on ozone exceedances (days with daily maximum 8 h average ? 60 ppb) is developed for Europe. We employ gridded observed daily maximum temperatures and hourly ozone observations from nonurban stations across Europe, together with daily maximum temperatures for 2021-2050 and 2071-2100 from three regional climate models, based on the Intergovernmental Panel on Climate Change Special Reports on Emissions Scenarios A1B scenario. A rotated principal components analysis is applied to the ozone stations yielding five principal components, which divide the study domain in five subregions. The historical ozone-temperature relationship is examined and then used to provide estimates of future ozone exceedance days under current emissions and under the assumption that this relationship will retain its main characteristics. Results suggest that increases in the upper temperature percentiles lead to statistically significant increases (95% statistical significance level) of the ozone exceedances for both future periods. The greatest average increases depending on the particular regional climate model range from 5 to 12 extra ozone days/yr for 2021-2050 and from 16 to 25 for 2071-2100, in southeast Europe. The lowest average increases range from 0 to 2 extra ozone days/yr for 2021-2050 and from 2 to 4 for 2071-2100 and are seen in northwest Europe. The simulations with the dynamical Goddard Institute of Space Studies/GEOS-CHEM climate chemistry modeling system shows decreases instead of increases in eastern Europe, higher increases in northwest Europe, whereas for the other subregions similar results to the statistical model are obtained.

  13. Calculating Confidence, Uncertainty, and Numbers of Samples When Using Statistical Sampling Approaches to Characterize and Clear Contaminated Areas

    SciTech Connect

    Piepel, Gregory F.; Matzke, Brett D.; Sego, Landon H.; Amidan, Brett G.

    2013-04-27

    This report discusses the methodology, formulas, and inputs needed to make characterization and clearance decisions for Bacillus anthracis-contaminated and uncontaminated (or decontaminated) areas using a statistical sampling approach. Specifically, the report includes the methods and formulas for calculating the • number of samples required to achieve a specified confidence in characterization and clearance decisions • confidence in making characterization and clearance decisions for a specified number of samples for two common statistically based environmental sampling approaches. In particular, the report addresses an issue raised by the Government Accountability Office by providing methods and formulas to calculate the confidence that a decision area is uncontaminated (or successfully decontaminated) if all samples collected according to a statistical sampling approach have negative results. Key to addressing this topic is the probability that an individual sample result is a false negative, which is commonly referred to as the false negative rate (FNR). The two statistical sampling approaches currently discussed in this report are 1) hotspot sampling to detect small isolated contaminated locations during the characterization phase, and 2) combined judgment and random (CJR) sampling during the clearance phase. Typically if contamination is widely distributed in a decision area, it will be detectable via judgment sampling during the characterization phrase. Hotspot sampling is appropriate for characterization situations where contamination is not widely distributed and may not be detected by judgment sampling. CJR sampling is appropriate during the clearance phase when it is desired to augment judgment samples with statistical (random) samples. The hotspot and CJR statistical sampling approaches are discussed in the report for four situations: 1. qualitative data (detect and non-detect) when the FNR = 0 or when using statistical sampling methods that account for FNR > 0 2. qualitative data when the FNR > 0 but statistical sampling methods are used that assume the FNR = 0 3. quantitative data (e.g., contaminant concentrations expressed as CFU/cm2) when the FNR = 0 or when using statistical sampling methods that account for FNR > 0 4. quantitative data when the FNR > 0 but statistical sampling methods are used that assume the FNR = 0. For Situation 2, the hotspot sampling approach provides for stating with Z% confidence that a hotspot of specified shape and size with detectable contamination will be found. Also for Situation 2, the CJR approach provides for stating with X% confidence that at least Y% of the decision area does not contain detectable contamination. Forms of these statements for the other three situations are discussed in Section 2.2. Statistical methods that account for FNR > 0 currently only exist for the hotspot sampling approach with qualitative data (or quantitative data converted to qualitative data). This report documents the current status of methods and formulas for the hotspot and CJR sampling approaches. Limitations of these methods are identified. Extensions of the methods that are applicable when FNR = 0 to account for FNR > 0, or to address other limitations, will be documented in future revisions of this report if future funding supports the development of such extensions. For quantitative data, this report also presents statistical methods and formulas for 1. quantifying the uncertainty in measured sample results 2. estimating the true surface concentration corresponding to a surface sample 3. quantifying the uncertainty of the estimate of the true surface concentration. All of the methods and formulas discussed in the report were applied to example situations to illustrate application of the methods and interpretation of the results.

  14. Reynolds number influence on statistical behaviors of turbulence in a circular free jet

    NASA Astrophysics Data System (ADS)

    Mi, J.; Xu, M.; Zhou, T.

    2013-07-01

    The present paper examines the effect of Reynolds number on turbulence properties in the transition region of a circular jet issuing from a smoothly contracting nozzle. Hot-wire measurements were performed for this investigation through varying the jet-exit Reynolds number Red (? Ujd/?, where Uj, d, and ? are the jet-exit mean velocity, nozzle diameter, and kinematic viscosity) approximately from Red ? 4 × 103 to Red ? 2 × 104. Results reveal that the rates of the mean flow decay and spread vary with Reynolds number for Red < 104 and tend to become Reynolds-number independent at Red ? 104. Even more importantly, the small-scale turbulence properties, e.g., the mean rate of dissipation of kinetic energy (?), the Kolmogorov and Taylor microscales, are found to vary in different forms over the Red ranges of Red > 104 and Red < 104. Namely, the critical Reynolds number appears to occur at Red,cr ? 104 across which the jet turbulence behaves distinctly. Two turbulence regimes are therefore identified: (i) developing or partially developed turbulence at Red < Red,cr and (ii) fully developed turbulence at Red ? Red,cr. It is suggested that the energy dissipation rate (DR) can be expressed as \\varepsilon ˜ ? U_c^2 /R^2 in regime (i) and \\varepsilon ˜ U_c^3 /R in regime (ii), where Uc and R are the centerline (or maximum) mean velocity and half-radius at which the mean velocity is 0.5Uc. In addition, the critical Reynolds number appears to vary from flow to flow.

  15. Majorana zero modes choose Euler numbers - revealed by full counting statistics

    NASA Astrophysics Data System (ADS)

    Liu, Dong E.; Levchenko, Alex; Lutchyn, Roman M.

    2015-03-01

    We consider a quantum dot (QD) coupled to a Majorana zero mode and two normal leads and study transport properties of the system. We investigate the full counting statistics of charge tunneling events which allows one to extract information about current fluctuations in the system. Using Keldysh path-integral approach, we compute the cumulant generating function for the quantum dot with Majorana and normal lead couplings. We first consider a non-interacting spinless QD, and find that for the symmetric dot-lead couplings, the zero-frequency cumulants exhibit a universal pattern (Euler polynomial), independent of the microscopic parameters. For a spinful QD, the Coulomb interaction effects are discussed for both strong interaction (single-electron occupancy regime) and weak interactions (perturbative regime). In the latter case, the interactions do not change the universal pattern at small voltage bias. Compared to the case without Majorana coupling, we show that, while the tunneling conductance might exhibit zero-bias anomaly due to Majorana or Kondo physics, the full counting statistics are qualitatively different in the presence of the Majorana coupling.

  16. Simultaneous Bearing and Number of Sources Estimation using Finite Set Statistics

    Microsoft Academic Search

    Andreas M. Ali

    Varying number of targets and sensors are a reality that needs to be addressed. Targets may come in and out the area of interest or may stop emitting detectable signal. Sensors can be subject to failure for various reasons, or some may go outside the range of the sensor cluster if it is mobile. We derive a tracking algorithm with

  17. A multivariate statistical approach to reducing the number of variables in data envelopment analysis

    Microsoft Academic Search

    Larry Jenkins; Murray Anderson

    2003-01-01

    The usefulness of data envelopment analysis (DEA) depends on its ability to calculate the relative efficiency of decision making units (DMUs) using multiple inputs and outputs. Unfortunately, the greater the number of input and output variables, the less discerning the analysis. In practice, the input and output variables are usually highly correlated with one another, often reflecting no more than

  18. Effective atomic numbers for photon energy absorption of essential amino acids in the energy range 1 keV to 20 MeV

    Microsoft Academic Search

    S. R. Manohara; S. M. Hanagodimath

    2007-01-01

    Effective atomic numbers for photon energy-absorption (ZPEAeff) of essential amino acids histidine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine have been calculated by a direct method in the energy region of 1keV to 20MeV. The ZPEAeff values have been found to change with energy and composition of the amino acids. The variations of mass energy-absorption coefficient, effective atomic number

  19. Identifying Copy Number Variants under Selection in Geographically Structured Populations Based on F-statistics

    PubMed Central

    Song, Hae-Hiang; Hu, Hae-Jin; Seok, In-Hae; Chung, Yeun-Jun

    2012-01-01

    Large-scale copy number variants (CNVs) in the human provide the raw material for delineating population differences, as natural selection may have affected at least some of the CNVs thus far discovered. Although the examination of relatively large numbers of specific ethnic groups has recently started in regard to inter-ethnic group differences in CNVs, identifying and understanding particular instances of natural selection have not been performed. The traditional FST measure, obtained from differences in allele frequencies between populations, has been used to identify CNVs loci subject to geographically varying selection. Here, we review advances and the application of multinomial-Dirichlet likelihood methods of inference for identifying genome regions that have been subject to natural selection with the FST estimates. The contents of presentation are not new; however, this review clarifies how the application of the methods to CNV data, which remains largely unexplored, is possible. A hierarchical Bayesian method, which is implemented via Markov Chain Monte Carlo, estimates locus-specific FST and can identify outlying CNVs loci with large values of FST. By applying this Bayesian method to the publicly available CNV data, we identified the CNV loci that show signals of natural selection, which may elucidate the genetic basis of human disease and diversity. PMID:23105934

  20. Quantum statistical properties of modes in a three-level atom with multiphoton transition interacting with two cavity fields

    SciTech Connect

    Shibing Lu (Jiangxi Normal Univ., Nanchang (China). Dept. of Physics)

    1993-01-01

    The quantum statistical properties of two field modes are studied for a three-level atom with multiphoton transition interacting with two cavity fields. By numerical calculations it is shown that, in the continual absorbing and emitting photons of the interacting system a photon submergence, the bunching and antibunching effects of two modes, exists. In addition, the impact of the atom's one transition photon numbers and the initial mean photon number of two modes on these effects are discussed in detail.

  1. The number statistics and optimal history of non-equilibrium steady states of mortal diffusing particles

    NASA Astrophysics Data System (ADS)

    Meerson, Baruch

    2015-05-01

    Suppose that a point-like steady source at x = 0 injects particles into a half-infinite line. The particles diffuse and die. At long times a non-equilibrium steady state sets in, and we assume that it involves many particles. If the particles are non-interacting, their total number N in the steady state is Poisson-distributed with mean \\bar{N} predicted from a deterministic reaction-diffusion equation. Here we determine the most likely density history of this driven system conditional on observing a given N. We also consider two prototypical examples of interacting diffusing particles: (i) a family of mortal diffusive lattice gases with constant diffusivity (as illustrated by the simple symmetric exclusion process with mortal particles), and (ii) random walkers that can annihilate in pairs. In both examples we calculate the variances of the (non-Poissonian) stationary distributions of N.

  2. Statistical analysis of some factors affecting the number of horse births in France.

    PubMed

    Langlois, Bertrand; Blouin, Christine

    2004-01-01

    Declarations of matings (535,746) and 308,549 consecutive declarations of birth from 1989 to 1999 were analysed by logistic regression in order to determine the effects of year, breed and age of parents on numerical productivity (the number of foals declared per mated mare per year). For the years 1994 to 1999, the status of the mare, type of mating and month of first mating, were also available. The effect of inbreeding and, for warm-blooded horses, the effect of the level of performances or the effect of the level of breeding value estimation were also analysed. The main results are the following: numerical productivity progressed in France more for draught breeds than for saddle breeds and trotters. Thoroughbreds progressed less and just reached the level of significance. Cold-blooded horses, however, appeared less productive than warm-blooded horses for which thoroughbreds were at the lower level. It cannot be concluded if this figure reveals biological differences in fertility or if it is only the result of differences in managing the official declarations. For warm-blooded horses, the absence of negative relationships between the trends of selection and numerical productivity results appeared clearly. A high performance level for the mare was positively associated with higher productivity results in sport and trotting horses and showed no significant influence for galloping horses. The relationships with breeding value estimation illustrated the same trends. PMID:15762302

  3. Functional analysis of fiber optic sensors using statistical photon counting: an automobile case study covered from quantum mechanics

    NASA Astrophysics Data System (ADS)

    Betancur, J. Alejandro

    2012-06-01

    Currently, the applications of fiber optic sensors on the automobile industry are gaining importance due to their potential for implementation in data acquisition and signal transmission. This paper covers from quantum mechanics, the photon counting in optical fibers using coherent states and generalized intelligent states, described by hyper-geometric functions and Bessel functions. Different fiber optic configurations will be showed, in order to show some representative factors that influence the probability of coherent and intelligent photons detected and transmitted by optical fibers. Finally, from the automotive industry, some applications are presented, from which the quantum-optical approach here proposed makes sense.

  4. Effective atomic numbers for photon energy absorption of essential amino acids in the energy range 1 keV to 20 MeV

    Microsoft Academic Search

    S. R. Manohara; S. M. Hanagodimath

    2007-01-01

    Effective atomic numbers for photon energy-absorption (ZPEAeff) of essential amino acids histidine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine have been calculated by a direct method in the energy region of 1 keV to 20 MeV. The ZPEAeff values have been found to change with energy and composition of the amino acids. The variations of mass energy-absorption coefficient, effective

  5. Statistical analysis on activation and photo-bleaching of step-wise multi-photon activation fluorescence of melanin

    NASA Astrophysics Data System (ADS)

    Gu, Zetong; Lai, Zhenhua; Zhang, Xi; Yin, Jihao; DiMarzio, Charles A.

    2015-03-01

    Melanin is regarded as the most enigmatic pigments/biopolymers found in most organisms. We have shown previously that melanin goes through a step-wise multi-photon absorption process after the fluorescence has been activated with high laser intensity. No melanin step-wise multi-photon activation fluorescence (SMPAF) can be obtained without the activation process. The step-wise multi-photon activation fluorescence has been observed to require less laser power than what would be expected from a non-linear optical process. In this paper, we examined the power dependence of the activation process of melanin SMPAF at 830nm and 920nm wavelengths. We have conducted research using varying the laser power to activate the melanin in a point-scanning mode for multi-photon microscopy. We recorded the fluorescence signals and position. A sequence of experiments indicates the relationship of activation to power, energy and time so that we can optimize the power level. Also we explored regional analysis of melanin to study the spatial relationship in SMPAF and define three types of regions which exhibit differences in the activation process.

  6. Statistical tests and chaotic synchronization based pseudorandom number generator for string bit sequences with application to image encryption

    NASA Astrophysics Data System (ADS)

    Hao, Longjie; Min, Lequan

    2014-06-01

    Recently, a stream encryption scheme using d-bit segment sequences has been proposed. This scheme may generate key avalanche effect. The randomness tests of d-bit segment pseudorandom number generator will be important for implementing such a scheme. Firstly this paper extends Beker and Piper's binary pseudorandom sequence statistical test suite to d-bit segment sequences case. Secondly, a novel 3-dimensional polynomial discrete chaotic map (3DPDCM) is proposed. The calculated Lyapunov exponents of the 3DPCDM are 0.213, 0.125 and - 3.228. Using the 3DPDCM constructs a 6-dimensional generalized synchronization chaotic system. Based on this system, a 8-bit segment chaotic pseudorandom number generator (CPRNG) is introduced. Using the generalized test suite tests 100 key streams generated via the 8-bit PRNG with different initial conditions and perturbed system parameters. The tested results are similar to those of the key streams generated via RC4 PRNG. As an application, using the key streams generated via the CPRNG and the RC4 PRNG encrypts an RGB image Landscape. The results have shown that the encrypted RGB images have significant avalanche effects. This research suggests that the requirements for PRNGs are not as strict as those under the traditional avalanche criteria. Suitable designed chaos-based d-bit string PRNGs may be qualified candidates for the stream encryption scheme with avalanche effect.

  7. Statistical performance evaluation and comparison of a Compton medical imaging system and a collimated Anger camera for higher energy photon imaging

    NASA Astrophysics Data System (ADS)

    Han, Li; Rogers, W. Leslie; Huh, Sam S.; Clinthorne, Neal

    2008-12-01

    In radionuclide treatment, tumor cells are primarily destroyed by charged particles emitted by the compound while associated higher energy photons are used to image the tumor in order to determine radiation dose and monitor shrinkage. However, the higher energy photons are difficult to image with conventional collimated Anger cameras, since a tradeoff exists between resolution and sensitivity, and the collimator septal penetration and scattering is increased due to the high energy photons. This research compares imaging performance of the conventional Anger camera to a Compton imaging system that can have improved spatial resolution and sensitivity for high energy photons because this tradeoff is decoupled, and the effect of Doppler broadening at higher gamma energies is decreased. System performance is analyzed by the modified uniform Cramer-Rao bound (M-UCRB) algorithms based on the developed system modeling. The bound shows that the effect of Doppler broadening is the limiting factor for Compton camera performance for imaging 364.4 keV photons emitted from 131I. According to the bound, the Compton camera outperforms the collimated system for an equal number of detected events when the desired spatial resolution for a 26 cm diameter uniform disk object is better than 12 mm FWHM. For a 3D cylindrical phantom, the lower bound on variance for the collimated camera is greater than for the Compton imaginer over the resolution range from 0.5 to 2 cm FWHM. Furthermore, the detection sensitivity of the proposed Compton imaging system is about 15-20 times higher than that of the collimated Anger camera.

  8. Fixed-scale statistics and the geometry of turbulent dispersion at high Reynolds number via numerical simulation

    NASA Astrophysics Data System (ADS)

    Hackl, Jason F.

    The relative dispersion of one uid particle with respect to another is fundamentally related to the transport and mixing of contaminant species in turbulent flows. The most basic consequence of Kolmogorov's 1941 similarity hypotheses for relative dispersion, the Richardson-Obukhov law that mean-square pair separation distance grows with the cube of time t3 at intermediate times in the inertial subrange, is notoriously difficult to observe in the environment, laboratory, and direct numerical simulations (DNS). Inertial subrange scaling in size parameters like requires careful adjustment for the initial conditions of the dispersion process as well as a very wide range of scales (high Reynolds number) in the flow being studied. However, the statistical evolution of the shapes of clusters of more than two particles has already exhibited statistical invariance at intermediate times in existing DNS. This invariance is identified with inertial-subrange scaling and is more readily observed than inertial-subrange scaling for the seemingly simpler quantity . Results from dispersion of clusters of four particles (called tetrads) in large-scale DNS at grid resolutions up to 40963 and Taylor-scale Reynolds numbers Rlambda from 140 to 1000 are used to explore the question of statistical universality in measures of the size and shape of tetrahedra in homogeneous isotropic turbulence in distinct scaling regimes at very small times (ballistic), intermediate times (inertial) and very late times (diffusive). Derivatives of 1/3 with respect to time normalized by the characteristic time scale at the initial tetrad size r0 constitute a powerful technique in isolating t3 scaling in . This technique is applied to the eigenvalues of a moment-of-inertia-like tensor formed from the separation vectors between particles in the tetrad. Estimates of the proportionality constant g in the Richardson-Obukhov t3 law from DNS at Rlambda ? 1000 converge towards the value g ? 0.56 reported in previous studies. The exit time taken by a particle pair to first reach successively larger thresholds of fixed separation distance is also brie y discussed and found to have unexplained dependence on initial separation distance for negative moments, but good inertial range scaling for positive moments. The use of diffusion models of relative dispersion in the inertial subrange to connect mean exit time to g is also tested and briefly discussed in these simulations. Mean values and probability density functions of shape parameters including the triangle aspect ratio w, tetrahedron volume-to-gyration radius ratio V2/3/R 2 and normalized moment-of-inertia eigenvalues are all found to approach invariant forms in the inertial subrange for a wider range of initial separations than size parameters such as mean-square gyration radius. These results constitute the clearest evidence to date that turbulence has a tendency to distort and elongate multiparticle configurations more severely in the inertial subrange than it does in the diffusive regime at asymptotically late time. Triangle statistics are found to be independent of initial shape for all time beyond the ballistic regime. The development and testing of different schemes for parallelizing the cubic spline interpolation procedure for particle velocities needed to track particles in DNS is also covered. A "pipeline" method of moving batches of particles from processor to processor is adopted due to its low memory overhead, but there are challenges in achieving good performance scaling.

  9. Statistical Analysis of Photonic Crystal Spectra for the Independent Determination of the Size and Refractive Index of Cells.

    PubMed

    Stewart, Justin William; Pyayt, Anna

    2015-07-01

    Photonic crystal flow cytometry is a very attractive platform due to its great sensitivity in combination with a very compact design. Previous studies have demonstrated the possibility to use spectral processing for the measurement of a wide range of parameters, from simple object counting to independent analysis of the buffer solution and immersed microscale objects. Here we propose to go to the next level and simultaneously determine the shape and the refractive index of the cells. PMID:26073041

  10. Volume 58A, number 3 PHYSICS LEUERS 23 August 1976 PHOTON ECHO MODULATION EFFECTS IN LaF3

    E-print Network

    - the ground multiplet with three substates in the cx- tion, however in the presence of an external field nuclear magnetic moments. Photon echoes arising from these ~ 0.5 coherently excited multilevel systems pulses are therefore able to connect every substate in moment would eliminate the F--Pr 3~magneticinterac

  11. Optimization of periodic single-photon sources

    NASA Astrophysics Data System (ADS)

    Adam, Peter; Mechler, Matyas; Santa, Imre; Koniorczyk, Mátyás

    2014-11-01

    We introduce a theoretical framework which is suitable for the description of all spatial and time-multiplexed periodic single-photon sources realized or proposed thus far. Our model takes into account all possibly relevant loss mechanisms. This statistical analysis of the known schemes shows that multiplexing systems can be optimized in order to produce maximal single-photon probability for various sets of loss parameters by the appropriate choice of the number of multiplexed units of spatial multiplexers or multiplexed time intervals and the input mean photon pair number and reveals the physical reasons of the existence of the optimum. We propose a time-multiplexed scheme to be realized in bulk optics, which, according to the present analysis, would have promising performance when experimentally realized. It could provide a single-photon probability of 85% with a choice of experimental parameters which are feasible according to the experiments known from the literature.

  12. Photon-Timing Jitter Dependence on Injection Position in Single-Photon Avalanche Diodes

    Microsoft Academic Search

    Mattia Assanelli; Antonino Ingargiola; Ivan Rech; Angelo Gulinatti; Massimo Ghioni

    2011-01-01

    In recent years, a growing number of applications demand better timing resolution from single-photon avalanche diodes (SPADs). The challenge is pursuing improved timing resolution without impairing other device characteristics such as quantum efficiency and dark count rate. This task requires a clear understanding of the statistical phenomena involved in the avalanche current growth in order to drive the device engineering

  13. Quantum noise evolution under optical Kerr effects and two-photon absorption in a semiconductor waveguide.

    PubMed

    Ju, Heongkyu; Lee, Eun-Cheol

    2008-03-01

    We theoretically study evolution of quantum noise of ultrashort pulsed light that propagates a semiconductor waveguide where nonlinear optical interaction occurs. Optical quantum noise is simulated by statistical (pseudo-)random distribution of phasors in a phase space with Gaussian probability weight, and each phasor evolution is governed by beam propagation method. It is shown that Kerr effects squeeze quantum noise of coherent light in a phase space such that photon-number noise is unchanged while phase noise increasing with uncertainty area invariant. However, two-photon absorption alters the photon-number statistics of light unlike Kerr effects. PMID:18542403

  14. Health Statistics NSW: getting the right balance between privacy and small numbers in a web-based reporting system.

    PubMed

    Scandol, James P; Moore, Helen A

    2012-01-01

    Health Statistics NSW is a new web-based application developed by the Centre for Epidemiology and Research at the NSW Ministry of Health. The application is designed to be an efficient vehicle for the timely delivery of health statistics to a diverse audience including the general public, health planners, researchers, students and policy analysts. The development and implementation of this web application required the consideration of a series of competing demands such as: the public interest in providing health data while maintaining the privacy interests of the individuals whose health is being reported; reporting data at spatial scales of relevance to health planners while maintaining the statistical integrity of any inferences drawn; the use of hardware and software systems which are publicly accessible, scalable and robust, while ensuring high levels of security. These three competing demands and the relationships between them are discussed in the context of Health Statistics NSW. PMID:22487325

  15. Photonic quantum well composed of photonic crystal and quasicrystal

    NASA Astrophysics Data System (ADS)

    Xu, Shaohui; Zhu, Yiping; Wang, Lianwei; Yang, Pingxiong; Chu, Paul K.

    2014-02-01

    A photonic quantum well structure composed of photonic crystal and Fibonacci quasicrystal is investigated by analyzing the transmission spectra and electric field distributions. The defect band in the photonic well can form confined quantized photonic states that can change in the band-gap of the photonic barriers by varying the thickness ratio of the two stacking layers. The number of confined states can be tuned by adjusting the period of the photonic well. The photons traverse the photonic quantum well by resonance tunneling and the coupling effect leads to the high transmission intensity of the confined photonic states.

  16. Calculation of effective atomic number and electron density of essential biomolecules for electron, proton, alpha particle and multi-energetic photon interactions

    NASA Astrophysics Data System (ADS)

    Kurudirek, Murat; Onaran, Tayfur

    2015-07-01

    Effective atomic numbers (Zeff) and electron densities (Ne) of some essential biomolecules have been calculated for total electron interaction, total proton interaction and total alpha particle interaction using an interpolation method in the energy region 10 keV-1 GeV. Also, the spectrum weighted Zeff for multi-energetic photons has been calculated using Auto-Zeff program. Biomolecules consist of fatty acids, amino acids, carbohydrates and basic nucleotides of DNA and RNA. Variations of Zeff and Ne with kinetic energy of ionizing charged particles and effective photon energies of heterogeneous sources have been studied for the given materials. Significant variations in Zeff and Ne have been observed through the entire energy region for electron, proton and alpha particle interactions. Non-uniform variation has been observed for protons and alpha particles in low and intermediate energy regions, respectively. The maximum values of Zeff have found to be in higher energies for total electron interaction whereas maximum values have found to be in relatively low energies for total proton and total alpha particle interactions. When it comes to the multi-energetic photon sources, it has to be noted that the highest Zeff values were found at low energy region where photoelectric absorption is the pre-dominant interaction process. The lowest values of Zeff have been shown in biomolecules such as stearic acid, leucine, mannitol and thymine, which have highest H content in their groups. Variation in Ne seems to be more or less the same with the variation in Zeff for the given materials as expected.

  17. U.S. Students Abroad: Statistics on Study Abroad, 1985/86. IIE Research Report Number 16.

    ERIC Educational Resources Information Center

    Zikopoulos, Marianthi, Ed.

    Statistics are provided on U.S. students overseas, with data coming from the Study Abroad Survey, a survey of 2,896 accredited U.S. institutions of higher education with 1,898 responding for a 65% response rate. Details are provided on the characteristics and destinations of the 48,483 students abroad. Reasons for the increase in study abroad…

  18. A Statistical Study of the Public Schools of the Southern Appalachian Mountains. Bulletin, 1915, No. 11. Whole Number 636

    ERIC Educational Resources Information Center

    Frost, Norman

    1915-01-01

    Information concerning educational conditions in the southern Appalachian region is scattered, fragmentary, and often partisan to the assumption either that conditions are ideal or that they are inconceivably bad. The purpose of this study is to draw together the available facts in the case. Necessarily, this study is largely statistical. The…

  19. Skin Conditions of Youths 12-17, United States. Vital and Health Statistics; Series 11, Number 157.

    ERIC Educational Resources Information Center

    Roberts, Jean; Ludford, Jacqueline

    This report of the National Center for Health Statistics presents national estimates of the prevalence of facial acne and other skin lesions among noninstitutionalized youths aged 12-17 years by age, race, sex, geographic region, population size of place of residence, family income, education of parent, overall health, indications of stress,…

  20. Statistical Significance

    NSDL National Science Digital Library

    This article may help the user understand the concept of statistical significance and the meaning of the numbers produced by The Survey System. This article is presented in two parts. The first part simplifies the concept of statistical significance as much as possible; so that non-technical readers can use the concept to help make decisions based on their data. The second part provides more technical readers with a fuller discussion of the exact meaning of statistical significance numbers.

  1. Home Range Size in Eastern Chipmunks, Tamias striatus, as a Function of Number of Captures: Statistical Biases of Inadequate Sampling

    E-print Network

    Willig, Michael

    Home Range Size in Eastern Chipmunks, Tamias striatus, as a Function of Number of Captures #12;HOME RANGE SIZE IN EASTERN CHIPMUNKS, TAMIAS STRIATUS, AS A FUNCTION O F NUMBER O F CAPTURES to identify factors accounting for variation in home range size. Home range is linearly dependent upon

  2. A bias free true random number generator

    E-print Network

    Wei Wei; Hong Guo

    2009-05-15

    We propose a new approach to nondeterministic random number generation. In theory, the randomness originated from the uncorrelated nature of consecutive laser pulses with Poissonian photon number distribution and that of the consecutive single photon detections is used to generate random bit. In experiment, von Neumann correction method is applied to extract the final random bit. This method is proved to be bias free in randomness generation, provided that the single photon detections are mutually independent, and further, it has the advantage in generation efficiency of random bits since no postprocessing is needed. A true random number generator based on this new method is realized and its randomness is guaranteed using three batteries of statistical tests.

  3. A bias free true random number generator

    E-print Network

    Wei, Wei

    2009-01-01

    We propose a new approach to nondeterministic random number generation. In theory, the randomness originated from the uncorrelated nature of consecutive laser pulses with Poissonian photon number distribution and that of the consecutive single photon detections is used to generate random bit. In experiment, von Neumann correction method is applied to extract the final random bit. This method is proved to be bias free in randomness generation, provided that the single photon detections are mutually independent, and further, it has the advantage in generation efficiency of random bits since no postprocessing is needed. A true random number generator based on this new method is realized and its randomness is guaranteed using three batteries of statistical tests.

  4. On-chip low loss heralded source of pure single photons

    NASA Astrophysics Data System (ADS)

    Spring, Justin B.; Salter, Patrick S.; Metcalf, Benjamin J.; Humphreys, Peter C.; Moore, Merritt; Thomas-Peter, Nicholas; Barbieri, Marco; Jin, Xian-Min; Langford, Nathan K.; Kolthammer, W. Steven; Booth, Martin J.; Walmsley, Ian A.

    2013-06-01

    A key obstacle to the experimental realization of many photonic quantum-enhanced technologies is the lack of low-loss sources of single photons in pure quantum states. We demonstrate a promising solution: generation of heralded single photons in a silica photonic chip by spontaneous four-wave mixing. A heralding efficiency of 40%, corresponding to a preparation efficiency of 80% accounting for detector performance, is achieved due to efficient coupling of the low-loss source to optical fibers. A single photon purity of 0.86 is measured from the source number statistics without filtering, and confirmed by direct measurement of the joint spectral intensity. We calculate that similar high-heralded-purity output can be obtained from visible to telecom spectral regions using this approach. On-chip silica sources can have immediate application in a wide range of single-photon quantum optics applications which employ silica photonics.

  5. On-chip low loss heralded source of pure single photons

    E-print Network

    Justin B. Spring; Patrick S. Salter; Benjamin J. Metcalf; Peter C. Humphreys; Merritt Moore; Nicholas Thomas-Peter; Marco Barbieri; Xian-Min Jin; Nathan K. Langford; W. Steven Kolthammer; Martin J. Booth; Ian A. Walmsley

    2013-04-29

    A key obstacle to the experimental realization of many photonic quantum-enhanced technologies is the lack of low-loss sources of single photons in pure quantum states. We demonstrate a promising solution: generation of heralded single photons in a silica photonic chip by spontaneous four-wave mixing. A heralding efficiency of 40%, corresponding to a preparation efficiency of 80% accounting for detector performance, is achieved due to efficient coupling of the low-loss source to optical fibers. A single photon purity of 0.86 is measured from the source number statistics without filtering, and confirmed by direct measurement of the joint spectral intensity. We calculate that similar high-heralded-purity output can be obtained from visible to telecom spectral regions using this approach. On-chip silica sources can have immediate application in a wide range of single-photon quantum optics applications which employ silica photonics.

  6. On-chip low loss heralded source of pure single photons

    E-print Network

    Spring, Justin B; Metcalf, Benjamin J; Humphreys, Peter C; Moore, Merritt; Thomas-Peter, Nicholas; Barbieri, Marco; Jin, Xian-Min; Langford, Nathan K; Kolthammer, W Steven; Booth, Martin J; Walmsley, Ian A

    2013-01-01

    A key obstacle to the experimental realization of many photonic quantum-enhanced technologies is the lack of low-loss sources of single photons in pure quantum states. We demonstrate a promising solution: generation of heralded single photons in a silica photonic chip by spontaneous four-wave mixing. A heralding efficiency of 40%, corresponding to a preparation efficiency of 80% accounting for detector performance, is achieved due to efficient coupling of the low-loss source to optical fibers. A single photon purity of 0.86 is measured from the source number statistics without filtering, and confirmed by direct measurement of the joint spectral intensity. We calculate that similar high-heralded-purity output can be obtained from visible to telecom spectral regions using this approach. On-chip silica sources can have immediate application in a wide range of single-photon quantum optics applications which employ silica photonics.

  7. Statistical Studies on Protein Polymorphism in Natural Populations. III. Distribution of Allele Frequencies and the Number of Alleles per Locus

    PubMed Central

    Chakraborty, Ranajit; Fuerst, Paul A.; Nei, Masatoshi

    1980-01-01

    With the aim of understanding the mechanism of maintenance of protein polymorphism, we have studied the properties of allele frequency distribution and the number of alleles per locus, using gene-frequency data from a wide range of organisms (mammals, birds, reptiles, amphibians, Drosophila and non-Drosophila invertebrates) in which 20 or more loci with at least 100 genes were sampled. The observed distribution of allele frequencies was U-shaped in all of the 138 populations (mostly species or subspecies) examined and generally agreed with the theoretical distribution expected under the mutation-drift hypothesis, though there was a significant excess of rare alleles (gene frequency, 0 ? 0.05) in about a quarter of the populations. The agreement between the mutation-drift theory and observed data was quite satisfactory for the numbers of polymorphic (gene frequency, 0.05 ? 0.95) and monomorphic (0.95 ? 1.0) alleles.—The observed pattern of allele-frequency distribution was incompatible with the prediction from the overdominance hypothesis. The observed correlations of the numbers of rare alleles, polymorphic alleles and monomorphic alleles with heterozygosity were of the order of magnitude that was expected under the mutation-drift hypothesis. Our results did not support the view that intracistronic recombination is an important source of genetic variation. The total number of alleles per locus was positively correlated with molecular weight in most of the species examined, and the magnitude of the correlation was consistent with the theoretical prediction from mutation-drift hypothesis. The correlation between molecular weight and the number of alleles was generally higher than the correlation between molecular weight and heterozygosity, as expected. PMID:17249018

  8. Implication of nonintegral occupation number and Fermi-Dirac statistics in the local-spin-density approximation applied to finite systems

    SciTech Connect

    Dhar, S.

    1989-02-01

    In electronic-structure calculations for finite systems using the local-spin-density (LSD) approximation, it is assumed that the eigenvalues of the Kohn-Sham equation should obey Fermi-Dirac (FD) statistics. In order to comply with this assumption for some of the transition-metal atoms, a nonintegral occupation number is used which also minimizes the total energy. It is shown here that for finite systems it is not necessary that the eigenvalues of the Kohn-Sham equation obey FD statistics. It is also shown that the Kohn-Sham exchange potential used in all LSD models is correct only for integer occupation number. With a noninteger occupation number the LSD exchange potential will be smaller than that given by the Kohn-Sham potential. Ab initio self-consistent spin-polarized calculations have been performed numerically for the total energy of an iron atom. It is found that the ground state belongs to the 3d/sup 6/4s/sup 2/ configuration. The ionization potentials of all the Fe/sup n//sup +/ ions are reported and are in agreement with experiment.

  9. Bias-free true random-number generator.

    PubMed

    Wei, Wei; Guo, Hong

    2009-06-15

    We propose what we believe to be a new approach to nondeterministic random-number generation. The randomness originated from the uncorrelated nature of consecutive laser pulses with Poissonian photon statistics and that of photon number detections is used to generate random bit, and the von Neumann correction method is used to extract the final random bit. This method is proved to be bias free in randomness generation, provided that the single photon detections are mutually independent. Further, it has the advantage in fast random bit generation, since no postprocessing is needed. A true random-number generator based on this method is realized, and its randomness is tested and guaranteed using three statistical test batteries. PMID:19529733

  10. Statistics of multiphoton events in spontaneous parametric down-conversion

    E-print Network

    Wojciech Wasilewski; Czeslaw Radzewicz; Robert Frankowski; Konrad Banaszek

    2008-05-12

    We present an experimental characterization of the statistics of multiple photon pairs produced by spontaneous parametric down-conversion realized in a nonlinear medium pumped by high-energy ultrashort pulses from a regenerative amplifier. The photon number resolved measurement has been implemented with the help of a fiber loop detector. We introduce an effective theoretical description of the observed statistics based on parameters that can be assigned direct physical nterpretation. These parameters, determined for our source from the collected experimental data, characterize the usefulness of down-conversion sources in multiphoton interference schemes that underlie protocols for quantum information processing and communication.

  11. On Asymptotic Properties of a Number Theoretic Function Arising out of a Spin Chain Modelin Statistical Mechanics

    NASA Astrophysics Data System (ADS)

    Kallies, J.; Özlük, A.; Peter, M.; Snyder, C.

    Let Let N be a positive integer and define ?(N) as the number of matrices, C, which are products of A and B, where both A and B must occur, such that the trace, Tr(C)=N. It has been conjectured that see [10]. In this note we consider the summatory function and show that

  12. On the Poisson Approximation to Photon Distribution for Faint Lasers

    E-print Network

    Yucheng Hu; Xiang Peng; Tiejun Li; Hong Guo

    2006-09-23

    It is proved, that for a certain kind of input distribution, the strongly binomially attenuated photon number distribution can well be approximated by a Poisson distribution. This explains why we can adopt poissonian distribution as the photon number statistics for faint lasers. The error of such an approximation is quantitatively estimated. Numerical tests are carried out, which coincide with our theoretical estimations. This work lays a sound mathematical foundation for the well-known intuitive idea which has been widely used in quantum cryptography.

  13. Reply on "Comment on 'Role of initial entanglement and non-Gaussianity in the decoherence of photon-number entangled states evolving in a noisy channel' "

    E-print Network

    Michele Allegra; Paolo Giorda; Matteo G. A. Paris

    2011-12-14

    In a recent work (Allegra et al, Phys. Rev. Lett. 105, 100503, 2010) we addressed the evolution of photon-number entangled states in noisy Gaussian channels. Upon exploiting several non equivalent separability criteria we found evidence that entanglement of Gaussian PNES survives longer, and thus we drew a conjecture about the generality of this result. In their Comment to our work, Lee et al. use an additional entanglement criterion (NDPT) which allows them to show some counterexamples to our conjecture, i.e., nonGaussian states whose entanglement survives longer. In this reply, we argue that although there are no flaws or central errors in our original Letter, the conjecture is not maintanable in a strict sense if one includes the NDPT criterion. Nevertheless, for the examples of non Gaussian states proposed in the Comment, which violate the conjecture, the residual entanglement is extremely low. Therefore it remains an open question whether these, as well as other kinds of states, could represent a useful resource in quantum communication protocols.

  14. Reply on "Comment on 'Role of initial entanglement and non-Gaussianity in the decoherence of photon-number entangled states evolving in a noisy channel' "

    E-print Network

    Allegra, Michele; Paris, Matteo G A

    2011-01-01

    In a recent work (Allegra et al, Phys. Rev. Lett. 105, 100503, 2010) we addressed the evolution of photon-number entangled states in noisy Gaussian channels. Upon exploiting several non equivalent separability criteria we found evidence that entanglement of Gaussian PNES survives longer, and thus we drew a conjecture about the generality of this result. In their Comment to our work, Lee et al. use an additional entanglement criterion (NDPT) which allows them to show some counterexamples to our conjecture, i.e., nonGaussian states whose entanglement survives longer. In this reply, we argue that although there are no flaws or central errors in our original Letter, the conjecture is not maintanable in a strict sense if one includes the NDPT criterion. Nevertheless, for the examples of non Gaussian states proposed in the Comment, which violate the conjecture, the residual entanglement is extremely low. Therefore it remains an open question whether these, as well as other kinds of states, could represent a useful ...

  15. Photonic Equations of Motion

    SciTech Connect

    Ritchie, A B; Crenshaw, M E

    2004-09-17

    Although the concept of the photon as a quantum particle is sharpened by the quantization of the energy of the classical radiation field in a cavity, the photon's spin has remained a classical degree of freedom. The photon is considered a spin-1 particle, although only two classical polarization states transverse to its direction of propagation are allowed. Effectively therefore the photon is a spin-1/2 particle, although it still obeys Bose-Einstein statistics because the photon-photon interaction is zero. Here they show that the two polarization states of the photon can be quantized using Pauli's spin vector, such that a suitable equation of motion for the photon is Dirac's relativistic wave equation for zero mass and zero charge. Maxwell's equations for a free photon are inferred from the Dirac-field formalism and thus provide proof of this claim. For photons in the presence of electronic sources for electromagnetic fields we posit Lorentz-invariant inhomogeneous photonic equations of motion. Electro-dynamic operator equations are inferred from this modified Dirac-field formalism which reduce to Maxwell's equations if spin-dependent terms in the radiation-matter interaction are dropped.

  16. Photon-assisted Landau-Zener transition: Role of coherent superposition states

    E-print Network

    Zhe Sun; Jian Ma; Xiaoguang Wang; Franco Nori

    2012-07-20

    We investigate a Landau-Zener (LZ) transition process modeled by a quantum two-level system (TLS) coupled to a photon mode when the bias energy is varied linearly in time. The initial state of the photon field is assumed to be a superposition of coherent states, leading to a more intricate LZ transition. Applying the rotating-wave approximation (RWA), analytical results are obtained revealing the enhancement of the LZ probability by increasing the average photon number. We also consider the creation of entanglement and the change of photon statistics during the LZ process. Without the RWA, we find some qualitative differences of the LZ dynamics from the RWA results, e.g., the average photon number no longer monotonically enhances the LZ probability. The ramifications and implications of these results are explored.

  17. RANDOMNESS of Numbers DEFINITION(QUERY:WHAT? V HOW?) ONLY Via MAXWELL-BOLTZMANN CLASSICAL-Statistics(MBCS) Hot-Plasma VS. Digits-Clumping Log-Law NON-Randomness Inversion ONLY BOSE-EINSTEIN QUANTUM-Statistics(BEQS) .

    NASA Astrophysics Data System (ADS)

    Siegel, Z.; Siegel, Edward Carl-Ludwig

    2011-03-01

    RANDOMNESS of Numbers cognitive-semantics DEFINITION VIA Cognition QUERY: WHAT???, NOT HOW?) VS. computer-``science" mindLESS number-crunching (Harrel-Sipser-...) algorithmics Goldreich "PSEUDO-randomness"[Not.AMS(02)] mea-culpa is ONLY via MAXWELL-BOLTZMANN CLASSICAL-STATISTICS(NOT FDQS!!!) "hot-plasma" REPULSION VERSUS Newcomb(1881)-Weyl(1914;1916)-Benford(1938) "NeWBe" logarithmic-law digit-CLUMPING/ CLUSTERING NON-Randomness simple Siegel[AMS Joint.Mtg.(02)-Abs. # 973-60-124] algebraic-inversion to THE QUANTUM and ONLY BEQS preferentially SEQUENTIALLY lower-DIGITS CLUMPING/CLUSTERING with d = 0 BEC, is ONLY VIA Siegel-Baez FUZZYICS=CATEGORYICS (SON OF TRIZ)/"Category-Semantics"(C-S), latter intersection/union of Lawvere(1964)-Siegel(1964)] category-theory (matrix: MORPHISMS V FUNCTORS) "+" cognitive-semantics'' (matrix: ANTONYMS V SYNONYMS) yields Siegel-Baez FUZZYICS=CATEGORYICS/C-S tabular list-format matrix truth-table analytics: MBCS RANDOMNESS TRUTH/EMET!!!

  18. STATISTICAL METHODS STATISTICAL METHODS

    E-print Network

    Delorme, Arnaud

    STATISTICAL METHODS 1 STATISTICAL METHODS Arnaud Delorme, Swartz Center for Computational@salk.edu. Keywords: statistical methods, inference, models, clinical, software, bootstrap, resampling, PCA, ICA Abstract: Statistics represents that body of methods by which characteristics of a population are inferred

  19. Photon Localization in Resonant Media

    NASA Astrophysics Data System (ADS)

    Genack, Azriel

    2002-03-01

    Unlike electrons that can be trapped by the Coulomb interaction at atomic sites, photons are not bound by individual particles. They may, however, be strongly scattered at Mie resonances, with the scattering cross section considerably exceeding the geometric cross section. We utilize Mie resonances to localize microwave radiation in low-density quasi-one dimensional samples of randomly positioned dielectric spheres. We explore factors that facilitate photon localization and probe the properties of localized waves. Sharp dips in the ensemble average of transmission and peaks in the average photon transit time are found near the first five Mie resonances. A decisive statistical test of photon localization, based on measurements of the variance of the intensity normalized by its ensemble average value, shows, however, that localization occurs only in a narrow window above the first Mie resonance. Measurements of this localization parameter are compared to measurements of the dimensionless conductance and of the Thouless number in samples with and without absorption. The Thouless number, which is the ratio of the width to the spacing of quasi-modes of a random medium, is obtained from measurements of the field correlation function with frequency shift and of the spacing between resonances in a sealed cavity. In samples with negligible absorption, these parameters coincide. The localization parameters reach a minimum within the window of localization as a result of collective scattering. In the presence of absorption, only the variance of intensity remains a reliable guide to localization. When the sample is cooled to 77 K to reduce absorption, narrow Lorentzian transmission peaks are observed as a result of resonant tunneling through long-lived localized modes. The enhancement of intensity in long-lived modes as the localization threshold is approached is related to sharp line lasing in random amplifying media. In collaboration with Andrey Chabanov.

  20. Photon calorimeter

    DOEpatents

    Chow, Tze-Show

    1988-04-22

    A photon calorimeter is provided that comprises a laminar substrate that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating, that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions, are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly. 4 figs.

  1. Photon Calorimeter

    DOEpatents

    Chow, Tze-Show (Hayward, CA)

    1989-01-01

    A photon calorimeter (20, 40) is provided that comprises a laminar substrate (10, 22, 42) that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating (28, 48, 52), that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions (30, 50, 54) are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly.

  2. Photonic Aharonov–Bohm effect in photon–phonon interactions

    PubMed Central

    Li, Enbang; Eggleton, Benjamin J.; Fang, Kejie; Fan, Shanhui

    2014-01-01

    The Aharonov–Bohm effect is one of the most intriguing phenomena in both classical and quantum physics, and associates with a number of important and fundamental issues in quantum mechanics. The Aharonov–Bohm effects of charged particles have been experimentally demonstrated and found applications in various fields. Recently, attention has also focused on the Aharonov–Bohm effect for neutral particles, such as photons. Here we propose to utilize the photon–phonon interactions to demonstrate that photonic Aharonov–Bohm effects do exist for photons. By introducing nonreciprocal phases for photons, we observe experimentally a gauge potential for photons in the visible range based on the photon–phonon interactions in acousto-optic crystals, and demonstrate the photonic Aharonov–Bohm effect. The results presented here point to new possibilities to control and manipulate photons by designing an effective gauge potential. PMID:24476790

  3. Photonic Aharonov-Bohm effect in photon-phonon interactions

    NASA Astrophysics Data System (ADS)

    Li, Enbang; Eggleton, Benjamin J.; Fang, Kejie; Fan, Shanhui

    2014-01-01

    The Aharonov-Bohm effect is one of the most intriguing phenomena in both classical and quantum physics, and associates with a number of important and fundamental issues in quantum mechanics. The Aharonov-Bohm effects of charged particles have been experimentally demonstrated and found applications in various fields. Recently, attention has also focused on the Aharonov-Bohm effect for neutral particles, such as photons. Here we propose to utilize the photon-phonon interactions to demonstrate that photonic Aharonov-Bohm effects do exist for photons. By introducing nonreciprocal phases for photons, we observe experimentally a gauge potential for photons in the visible range based on the photon-phonon interactions in acousto-optic crystals, and demonstrate the photonic Aharonov-Bohm effect. The results presented here point to new possibilities to control and manipulate photons by designing an effective gauge potential.

  4. Photonic Aharonov-Bohm effect in photon-phonon interactions.

    PubMed

    Li, Enbang; Eggleton, Benjamin J; Fang, Kejie; Fan, Shanhui

    2014-01-01

    The Aharonov-Bohm effect is one of the most intriguing phenomena in both classical and quantum physics, and associates with a number of important and fundamental issues in quantum mechanics. The Aharonov-Bohm effects of charged particles have been experimentally demonstrated and found applications in various fields. Recently, attention has also focused on the Aharonov-Bohm effect for neutral particles, such as photons. Here we propose to utilize the photon-phonon interactions to demonstrate that photonic Aharonov-Bohm effects do exist for photons. By introducing nonreciprocal phases for photons, we observe experimentally a gauge potential for photons in the visible range based on the photon-phonon interactions in acousto-optic crystals, and demonstrate the photonic Aharonov-Bohm effect. The results presented here point to new possibilities to control and manipulate photons by designing an effective gauge potential. PMID:24476790

  5. Impact of Geometry on the TM Photonic Band Gaps of Photonic Crystals and Quasicrystals

    E-print Network

    Bita, Ion

    Here we demonstrate a novel quantitative procedure to pursue statistical studies on the geometric properties of photonic crystals and photonic quasicrystals (PQCs) which consist of separate dielectric particles. The geometric ...

  6. Interference of dissimilar photon sources

    E-print Network

    Bennett, A J; Nicoll, C A; Ritchie, D A; Shields, A J; 10.1038/nphys1373

    2010-01-01

    If identical photons meet at a semi-transparent mirror they appear to leave in the same direction, an effect called "two-photon interference". It has been known for some time that this effect should occur for photons generated by dissimilar sources with no common history, provided the easurement cannot distinguish between the photons. Here we report a technique to observe such interference with isolated, unsynchronized sources whose coherence times differ by several orders of magnitude. In an experiment we interfere photons generated via different physical processes, with different photon statistics. One source is stimulated emission from a tuneable laser, which has Poissonian statistics and a nano-eV bandwidth. The other is spontaneous emission from a quantum dot in a p-i-n diode with a micro-eV linewidth. We develop a theory to explain the visibility of interference, which is primarily limited by the timing resolution of our detectors.

  7. Silicon active photonic devices

    NASA Astrophysics Data System (ADS)

    Dimitropoulos, Dimitrios

    Active photonic devices utilizing the optical nonlinearities of silicon have emerged in the last 5 years and the effort for commercial photonic devices in the material that has been the workhorse of electronics has been building up since. This dissertation presents the theory for some of these devices. We are concerned herein with CW lasers, amplifiers and wavelength converters that are based on the Raman effect. There have already been cursory experimental demonstrations of these devices and some of their limitations are already apparent. Most of the limitations observed are because of the appearance of effects that are competing with stimulated Raman scattering. Under the high optical powers that are necessary for the Raman effect (tens to hundrends of mW's) the process of optical two-photon (TPA) absorption occurs. The absorption of optical power that it causes itself is weak but in the process electrons and holes are generated which can further absorb light through the free-carrier absorption effect (FCA). The effective "lifetime" that these carriers have determines the magnitude of the FCA loss. We present a model for the carrier lifetime in Silicon-On-Insulator (SOI) waveguides and numerical simulations to understand how this critical parameter varies and how it can be controlled. A p-i-n junction built along SOI waveguides can help achieve lifetime of the order of 20--100 ps but the price one has to pay is on-chip electrical power consumption on the order of 100's of mWs. We model CW Raman lasers and we find that the carrier lifetime reduces the output power. If the carrier lifetime exceeds a certain "critical" value optical losses become overwhelming and lasing is impossible. As we show, in amplifiers, the nonlinear loss does not only result in diminished gain, but also in a higher noise figure. Finally the effect of Coherent anti-Stokes Raman scattering (CARS) is examined. The effect is important because with a pump frequency at 1434nm coherent power transfer can take place between the 1300nm and 1500nm bands which are important for communications. Because of the importance of this process as a potential wavelength converter we examine the fundamental noise figure and photon statistics involved (when FCA losses are absent). We find that the wavelength conversion process has a minimum noise figure close to 3dB. The deviation from that number depends on a single parameter which itself depends on: the ratio of the Raman susceptibilities, the ratio of the indices of refraction and the ratio of frequencies between Stokes and anti-Stokes waves.

  8. VOLUME 76, NUMBER 12 P H Y S I C A L R E V I E W L E T T E R S 18 MARCH 1996 Avalanches in the Lung: A Statistical Mechanical Model

    E-print Network

    Stanley, H. Eugene

    VOLUME 76, NUMBER 12 P H Y S I C A L R E V I E W L E T T E R S 18 MARCH 1996 Avalanches in the Lung: A Statistical Mechanical Model Albert-László Barabási,1,2 Sergey V. Buldyrev,1 H. Eugene Stanley,1 and Béla Suki (Received 10 March 1995) We study a statistical mechanical model for the dynamics of lung inflation which

  9. VOLUME 78, NUMBER 25 P H Y S I C A L R E V I E W L E T T E R S 23 JUNE 1997 Statistics of Earthquakes in Simple Models of Heterogeneous Faults

    E-print Network

    Ben-Zion, Yehuda

    of behavior and analyze the origin of the power-law statistics and departures from it in these systemsVOLUME 78, NUMBER 25 P H Y S I C A L R E V I E W L E T T E R S 23 JUNE 1997 Statistics-Zion Department of Earth Sciences, University of Southern California, Los Angeles, California 90089-0740 (Received

  10. Accidental cloning of a single-photon qubit in two-channel continuous-variable quantum teleportation

    SciTech Connect

    Ide, Toshiki; Hofmann, Holger F. [Okayama Institute for Quantum Physics, 1-9-1 Kyoyama, Okayama City, Okayama, 700-0015 (Japan); JST-CREST, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashi Hiroshima 739-8530 (Japan)

    2007-06-15

    The information encoded in the polarization of a single photon can be transferred to a remote location by two-channel continuous-variable quantum teleportation. However, the finite entanglement used in the teleportation causes random changes in photon number. If more than one photon appears in the output, the continuous-variable teleportation accidentally produces clones of the original input photon. In this paper, we derive the polarization statistics of the N-photon output components and show that they can be decomposed into an optimal cloning term and completely unpolarized noise. We find that the accidental cloning of the input photon is nearly optimal at experimentally feasible squeezing levels, indicating that the loss of polarization information is partially compensated by the availability of clones.

  11. Number Watch

    NSDL National Science Digital Library

    John Brignell, Professor Emeritus from the Department of Electronics & Computer Science at the University of Southampton, is the author of this informal website "devoted to the monitoring of the misleading numbers that rain down on us via the media." Brignell says he aims to "nail" a few of the "Single Issue Fanatics (SIFs), politicians, bureaucrats, quasi-scientists (junk, pseudo- or just bad)," who use misleading numbers to write catchy articles or who try to keep numbers away from public notice. Since April 2000, he has been posting a "number of the month" as well as a "number for the year," which offer his commentary on media usage of misleading numbers and explanations for why the numbers are misleading. He also posts book reviews and an extensive list of online resources on statistics and statistics education. The FAQ section includes answers to some interesting questions, such as "Is there such a thing as average global temperature?" and some more basic questions such as "What is the Normal Distribution and what is so normal about it?" The Bits and Pieces section includes a variety of short articles on statistics and his definitions for some terms he uses on the website. Visitors are also invited to join the discussion forum (complete with a few advertisements) and view comments by others who want to discuss "wrong numbers in science, politics and the media." A few comments sent to Brignell and his responses are also posted online. This site is also reviewed in the February 11, 2005_NSDL MET Report_.

  12. Statistics Indonesia

    NSDL National Science Digital Library

    Started in 1997, the Badan Pusat Statistik (BPS-Statistics Indonesia) is a non-departmental Indonesian government institution directly responsible to the Indonesian president. As the law that created this valuable institution stipulates, the BPS is intended to provide data to the government and the public, along cooperating with other international statistical institutions. Visitors looking for statistics on any number of topics will not be disappointed, as the areas covered include agriculture, consumer price indices, employment, energy, foreign trade, mining, population, public finance, tourism, and social welfare. Additionally, there are monthly macro-economic statistical reports for the years from 1998 to 2001 that can be downloaded and viewed as well. The site is rounded out by a collection of some 21 papers from the past four years that analyze various economic data from the country, such as earning data and manufacturing production.

  13. Photoelectron anticorrelations and sub-Poisson statistics in scintillation detectors

    PubMed Central

    Bousselham, Abdelkader; Barrett, Harrison H.; Bora, Vaibhav; Shah, Kanai

    2010-01-01

    The performance of scintillation detectors for x rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to studying these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number the photoelectrons produced on the photocathode of the photomultiplier and for the underlying number of scintillation photons, can be deduced from these correlations. For LaBr3(Ce) and 662 keV gamma rays, the photopeak signals obtained by photomultipliers on opposite faces of a thin sample are negatively correlated, and the Fano factor for the photoelectrons is significantly less than one. The inferred Fano factor for the optical photons is very small, indistinguishable from zero within experimental error. PMID:20725609

  14. Auxiliary Entanglement in Photon Pairs for Multi-Photon Entanglement

    SciTech Connect

    Grice, Warren P [ORNL; Bennink, Ryan S [ORNL; Evans, Philip G [ORNL; Humble, Travis S [ORNL; Schaake, Jason [ORNL

    2012-01-01

    A growing number of experiments make use of multiple pairs of photons generated in the process of spontaneous parametric down-conversion. We show that entanglement in unwanted degrees of freedom can adversely affect the results of these experiments. We also discuss techniques to reduce or eliminate spectral and spatial entanglement, and we present results from two-photon polarization-entangled source with almost no entanglement in these degrees of freedom. Finally, we present two methods for the generation of four-photon polarization- entangled states. In one of these methods, four-photon can be generated without the need for intermediate two-photon entanglement.

  15. Lifetime statistics of quantum chaos studied by a multiscale analysis

    SciTech Connect

    Di Falco, A.; Krauss, T. F. [School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, KY16 9SS (United Kingdom); Fratalocchi, A. [PRIMALIGHT, Faculty of Electrical Engineering, Applied Mathematics and Computational Science, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia)

    2012-04-30

    In a series of pump and probe experiments, we study the lifetime statistics of a quantum chaotic resonator when the number of open channels is greater than one. Our design embeds a stadium billiard into a two dimensional photonic crystal realized on a silicon-on-insulator substrate. We calculate resonances through a multiscale procedure that combines energy landscape analysis and wavelet transforms. Experimental data is found to follow the universal predictions arising from random matrix theory with an excellent level of agreement.

  16. Statistical Applets: Animated Exercise

    NSDL National Science Digital Library

    Duckworth, William

    This collection of statistical applets is designed to accompany the textbook, "Practice of Business Statistics." The applets can be used without the textbook and cover many introductory statistics concepts including mean, normal curve, correlation and regression, probability, the law of large numbers, the central limit theorem, confidence intervals, statistical significance, power, and ANOVA. This is a great collection of interactive materials for either instructors or students studying statistics.

  17. Quantum Storage of a Photonic Polarization Qubit in a Solid

    E-print Network

    Mustafa Gündo?an; Patrick M. Ledingham; Attaallah Almasi; Matteo Cristiani; Hugues de Riedmatten

    2012-01-20

    We report on the quantum storage and retrieval of photonic polarization quantum bits onto and out of a solid state storage device. The qubits are implemented with weak coherent states at the single photon level, and are stored for 500 ns in a praseodymium doped crystal with a storage and retrieval efficiency of 10%, using the atomic frequency comb scheme. We characterize the storage by using quantum state tomography, and find that the average conditional fidelity of the retrieved qubits exceeds 95% for a mean photon number mu=0.4. This is significantly higher than a classical benchmark, taking into account the Poissonian statistics and finite memory efficiency, which proves that our device functions as a quantum storage device for polarization qubits, even if tested with weak coherent states. These results extend the storage capabilities of solid state quantum memories to polarization encoding, which is widely used in quantum information science.

  18. Two-photon emission processes in electron-atom interactions

    NASA Astrophysics Data System (ADS)

    Quarles, C. A.; Lehtihet, H. E.; Lawrence, D. J.; Kahler, D. L.

    1991-05-01

    We will describe the experimental techniques and preliminary results of an on-going three-parameter coincidence experiment in which two-photon spectra are obtained by electron bombardment of target foils of selected thicknesses. The atomic number of the foils ranges from Z = 26 to 82. Incident electrons have been provided both by the ? spectrum of a 147Pm source and by a 50-150 keV electron beam from an accelerator. Processes considered to date include: double bremsstrahlung, double innershell ionization, and coherent emission of both a characteristic and a continuum X-ray. The cross sections for these two-photon processes are much smaller than the processes that produce single photons in the target. This can lead typically to a large accidental rate in the accelerator experiment, or accentuate the need for a target thickness study of the real rate in the source experiment where thicker targets have been used to increase the statistics.

  19. Statistical Applets: Statistical Significance

    NSDL National Science Digital Library

    Duckworth, William

    Created by authors Duckworth, McCabe, Moore and Sclove for W.H. Freeman of Co., this applet is designed to help students visualize the rejection region of a statistical test by allowing them to set null and alternate hypotheses, population parameters, sample statistics, and significance level. It accompanies "Â?Â?Practice of Business Statistics," but can be used without this text. Even though brief, this is a nice interactive resource for an introductory statistics course.

  20. Housing and Disability: Data Needs, Statistics and Policy. Proceedings of the National Disability Statistics and Policy Forum (3rd, Washingon, DC, May 13, 1996). Disability Forum Report, Number 3.

    ERIC Educational Resources Information Center

    LaPlante, Mitchell P., Ed.; Kaye, H. Stephen, Ed.

    This proceedings reports on a forum which explored housing statistics for people with disabilities. An introduction identifies three broad areas of recommendations for consideration that arose from the forum: (1) a definition (and taxonomy) of housing that meets current and future profiles of where people actually live should be developed: (2)…

  1. Prospects for in vivo estimation of photon linear attenuation coefficients using postprocessing dual-energy CT imaging on a commercial scanner: Comparison of analytic and polyenergetic statistical reconstruction algorithms

    PubMed Central

    Evans, Joshua D.; Whiting, Bruce R.; O’Sullivan, Joseph A.; Politte, David G.; Klahr, Paul H.; Yu, Yaduo; Williamson, Jeffrey F.

    2013-01-01

    Purpose: Accurate patient-specific photon cross-section information is needed to support more accurate model-based dose calculation for low energy photon-emitting modalities in medicine such as brachytherapy and kilovoltage x-ray imaging procedures. A postprocessing dual-energy CT (pDECT) technique for noninvasive in vivo estimation of photon linear attenuation coefficients has been experimentally implemented on a commercial CT scanner and its accuracy assessed in idealized phantom geometries. Methods: Eight test materials of known composition and density were used to compare pDECT-estimated linear attenuation coefficients to NIST reference values over an energy range from 10 keV to 1 MeV. As statistical image reconstruction (SIR) has been shown to reconstruct images with less random and systematic error than conventional filtered backprojection (FBP), the pDECT technique was implemented with both an in-house polyenergetic SIR algorithm, alternating minimization (AM), as well as a conventional FBP reconstruction algorithm. Improvement from increased spectral separation was also investigated by filtering the high-energy beam with an additional 0.5 mm of tin. The law of propagated uncertainty was employed to assess the sensitivity of the pDECT process to errors in reconstructed images. Results: Mean pDECT-estimated linear attenuation coefficients for the eight test materials agreed within 1% of NIST reference values for energies from 1 MeV down to 30 keV, with mean errors rising to between 3% and 6% at 10 keV, indicating that the method is unbiased when measurement and calibration phantom geometries are matched. Reconstruction with FBP and AM algorithms conferred similar mean pDECT accuracy. However, single-voxel pDECT estimates reconstructed on a 1 × 1 × 3 mm3 grid are shown to be highly sensitive to reconstructed image uncertainty; in some cases pDECT attenuation coefficient estimates exhibited standard deviations on the order of 20% around the mean. Reconstruction with the statistical AM algorithm led to standard deviations roughly 40% to 60% less than FBP reconstruction. Additional tin filtration of the high energy beam exhibits similar pDECT estimation accuracy as the unfiltered beam, even when scanning with only 25% of the dose. Using the law of propagated uncertainty, low Z materials are found to be more sensitive to image reconstruction errors than high Z materials. Furthermore, it is estimated that reconstructed CT image uncertainty must be limited to less than 0.25% to achieve a target linear-attenuation coefficient estimation uncertainty of 3% at 28 keV. Conclusions: That pDECT supports mean linear attenuation coefficient measurement accuracies of 1% of reference values for energies greater than 30 keV is encouraging. However, the sensitivity of the pDECT measurements to noise and systematic errors in reconstructed CT images warrants further investigation in more complex phantom geometries. The investigated statistical reconstruction algorithm, AM, reduced random measurement uncertainty relative to FBP owing to improved noise performance. These early results also support efforts to increase DE spectral separation, which can further reduce the pDECT sensitivity to measurement uncertainty. PMID:24320525

  2. Controlling photon transport in the single-photon weak-coupling regime of cavity optomechanics

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-Zhao; Cheng, Jiong; Liu, Jing-Yi; Zhou, Ling

    2015-06-01

    We study the photon statistics properties of few-photon transport in an optomechanical system where an optomechanical cavity couples to two empty cavities. By analytically deriving the one- and two-photon currents in terms of a zero-time-delayed two-order correlation function, we show that a photon blockade can be achieved in both the single-photon strong-coupling regime and the single-photon weak-coupling regime due to the nonlinear interacting and multipath interference. Furthermore, our systems can be applied as a quantum optical diode, a single-photon source, and a quantum optical capacitor. It is shown that this the photon transport controlling devices based on photon antibunching does not require the stringent single-photon strong-coupling condition. Our results provide a promising platform for the coherent manipulation of optomechanics, which has potential applications for quantum information processing and quantum circuit realization.

  3. Photon counting.

    PubMed

    Morton, G A

    1968-01-01

    The fundamentals of photon counting using photomultipliers are described, including criteria for selecting suitable photomultipliers, some of the precautions that must be taken in using these devices, and methods of calculating the counting errors that may occur under various conditions of measurement. Problems of determining the time distribution of photons and, in particular, the coincident emission of photons which may be encountered in lasers and other simulated emission sources are also discussed. The question of photon counting with photoconductors is reviewed, and it is shown that it is extremely difficult, if not impossible, to achieve photon counting with simple photoconductors. However, carrier multiplication with photoconductive multipliers should eventually make possible photon counting with photoconductors. Photoconductive multipliers in one form or another have high quantum efficiency and wide spectral response, and will almost inevitably replace photomultipliers for photon counting. PMID:20062394

  4. Circuit QED Photonics

    NASA Astrophysics Data System (ADS)

    Zueco, David; Sánchez-Burillo, Eduardo; García-Ripoll, Juanjo; Martín-Moreno, Luis

    2015-03-01

    In this talk we report our theoretical results for the scattering of few photons against few two level systems. The photons travel through an open superconducting coplanar waveguide transmission line and the two level systems can be flux qubits or transmons. Several phenomena will be discussed: the linear and nonlinear behavior as a function of the ratio between the number of photons and number of qubits. For the case of flux qubits we discuss the cases of strong and ultrastrong line-qubits coupling. Different phenomena are found and described: Fano profiles, Raman scattering, photon generation and novel and non-perturbative qubit-qubit interecations through the line. Finally, we consider the case of transmon qubits. We theoretically demonstrate that driven transmons can be used as a minimal setup for doing up and downcoversion. By minimal, we mean that sending just one photon two photons are generated through the qubit. In our calculations, the parameters are taken from the chip reported in a recent Science paper by the Wallraff group [van Loo et al, Science 342, 1494 (2013)] .

  5. Deconstructing Statistics Anxiety.

    ERIC Educational Resources Information Center

    Earley, Mark A.; Mertler, Craig A.

    A number of scales have been developed to measure the construct of statistics anxiety, the anxiety students feel when they take a statistics course, but few researchers have examined whether this anxiety is due solely to being enrolled in a statistics course or if there is some component that is simply a function of being a student (anxiety in any…

  6. Generation of single-mode SU(1,1) intelligent states and an analytic approach to their quantum statistical properties

    E-print Network

    C. Brif; A. Mann

    1997-07-03

    We discuss a scheme for generation of single-mode photon states associated with the two-photon realization of the SU(1,1) algebra. This scheme is based on the process of non-degenerate down-conversion with the signal prepared initially in the squeezed vacuum state and with a measurement of the photon number in one of the output modes. We focus on the generation and properties of single-mode SU(1,1) intelligent states which minimize the uncertainty relations for Hermitian generators of the group. Properties of the intelligent states are studied by using a ``weak'' extension of the analytic representation in the unit disk. Then we are able to obtain exact analytical expressions for expectation values describing quantum statistical properties of the SU(1,1) intelligent states. Attention is mainly devoted to the study of photon statistics and linear and quadratic squeezing.

  7. Dow Corning photonics: the silicon advantage in automotive photonics

    Microsoft Academic Search

    Terry V. Clapp; Rene Paquet; Ann Norris; Babette Pettersen

    2005-01-01

    The Automotive Market offers several opportunities for Dow Corning to leverage the power of silicon-based materials. Dow Corning Photonics Solutions has a number of developments that may be attractive for the emergent photonics needs in automobiles, building on 40 years of experience as a leading Automotive supplier with a strong foundation of expertise and an extensive product offering- from encapsulents

  8. Quantum Interference Induced Photon Blockade in a Coupled Single Quantum Dot-Cavity System

    PubMed Central

    Tang, Jing; Geng, Weidong; Xu, Xiulai

    2015-01-01

    We propose an experimental scheme to implement a strong photon blockade with a single quantum dot coupled to a nanocavity. The photon blockade effect can be tremendously enhanced by driving the cavity and the quantum dot simultaneously with two classical laser fields. This enhancement of photon blockade is ascribed to the quantum interference effect to avoid two-photon excitation of the cavity field. Comparing with Jaynes-Cummings model, the second-order correlation function at zero time delay g(2)(0) in our scheme can be reduced by two orders of magnitude and the system sustains a large intracavity photon number. A red (blue) cavity-light detuning asymmetry for photon quantum statistics with bunching or antibunching characteristics is also observed. The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field. Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system. This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing. PMID:25783560

  9. Injury Statistics

    MedlinePLUS

    ... Data Consumer Opinion Surveys Home / Research & Statistics Injury Statistics This is the statistic reports page for scientific ... Home Appliances, Maintenance and Construction Injury Statistics Injury Statistics September 30, 2012 Submersions Related to Non-Pool ...

  10. Entangled Photon Fluorescence with Organic Conjugated Dendrimers

    NASA Astrophysics Data System (ADS)

    Upton, Leslie; Goodson, Theodore

    2012-02-01

    The use of entangled photons for spectroscopy is a novel technique with several potential applications in entangled two-photon excited fluorescence microscopy, quantum imaging and remote sensing. Classical TPA depends quadratically on the input photon flux, whereas, non-classical entangled two-photon absorption (ETPA) has a linear dependence on input flux rate. The total TPA rate measured using an entangled photon source is given by the summation of the ETPA rate and the random TPA rate. This work focuses on the entangled two-photon absorption cross-section and the entangled two-photon fluorescence efficiency of a G1 Dendrimer. From these results, it is shown that the entangled two-photon excited fluorescence of the G1 Dendrimer has a linear dependence at low input photon fluxes. This result has great impact on spectroscopy where the need for small numbers of photons is great, such as microscopy and sensing.

  11. VOLUME 80, NUMBER 11 P H Y S I C A L R E V I E W L E T T E R S 16 MARCH 1998 Observation of "Photon-Assisted" Shot Noise in a Phase-Coherent Conductor

    E-print Network

    Devoret, Michel H.

    Aharonov-Bohm effect," which should be observable in the shot noise of a phase-coherent conduc- tor under and the I-V curve are unaffected. The observed effect bears a strong resemblance to photonVOLUME 80, NUMBER 11 P H Y S I C A L R E V I E W L E T T E R S 16 MARCH 1998 Observation of "Photon

  12. Occupancy Numbers in Testing Random Number Generators

    Microsoft Academic Search

    A. Figotin; A. Gordon; J. Quinn; N. Stavrakas; S. Molchanov

    2002-01-01

    Abstract. The classical occupancy,problem,where n balls are placed in N cells is used for testing of random,number generators. We show that the statistics of appropriately chosen occupancy numbers,are incompatible with the statistics of many,pseudorandom,number,generators (PRNGs) evenif they are trun cated. More thanthat, the in compatibility shows up onrelatively small samples long before the period of the PRNG is reached. We

  13. Likelihood functions for the analysis of single-molecule binned photon sequences

    PubMed Central

    Gopich, Irina V.

    2011-01-01

    We consider the analysis of a class of experiments in which the number of photons in consecutive time intervals is recorded. Sequence of photon counts or, alternatively, of FRET efficiencies can be studied using likelihood-based methods. For a kinetic model of the conformational dynamics and state-dependent Poisson photon statistics, the formalism to calculate the exact likelihood that this model describes such sequences of photons or FRET efficiencies is developed. Explicit analytic expressions for the likelihood function for a two-state kinetic model are provided. The important special case when conformational dynamics are so slow that at most a single transition occurs in a time bin is considered. By making a series of approximations, we eventually recover the likelihood function used in hidden Markov models. In this way, not only is insight gained into the range of validity of this procedure, but also an improved likelihood function can be obtained. PMID:22711967

  14. Single-Photon Detection Timing Jitter in a Visible Light Photon Counter

    Microsoft Academic Search

    Burm Baek; K. S. McKay; M. J. Stevens; Jungsang Kim; Henry H. Hogue; Sae Woo Nam

    2010-01-01

    Visible light photon counters (VLPCs) offer many attractive features as photon detectors, such as high quantum efficiency and photon number resolution. We report measurements of the single-photon timing jitter in a VLPC, a critical performance factor in a time-correlated single-photon counting measurement, in a fiber-coupled closed-cycle cryocooler. The measured timing jitter is 240 ps full-width-at-half-maximum at a wavelength of 550

  15. Nonclassicality and decoherence of photon-subtracted squeezed states

    SciTech Connect

    Biswas, Asoka [Department of Chemistry, University of Southern California, Los Angeles, California 90089 (United States); Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

    2007-03-15

    We discuss nonclassical properties of single-photon subtracted squeezed vacuum states in terms of the sub-Poissonian statistics and the negativity of the Wigner function. We derive a compact expression for the Wigner function from which we find the region of phase space where Wigner function is negative. We find an upper bound on the squeezing parameter for the state to exhibit sub-Poissonian statistics. We then study the effect of decoherence on the single-photon subtracted squeezed states. We present results for two different models of decoherence, viz. amplitude decay model and the phase diffusion model. In each case we give analytical results for the time evolution of the state. We discuss the loss of nonclassicality as a result of decoherence. We show through the study of their phase-space properties how these states decay to vacuum due to the decay of photons. We show that phase damping leads to very slow decoherence, slower than the photon-number decay.

  16. Statistics of protein-DNA binding and the total number of binding sites for a transcription factor in the mammalian genome

    Microsoft Academic Search

    Vladimir A Kuznetsov; Onkar Singh; Piroon Jenjaroenpun

    2010-01-01

    BACKGROUND: Transcription factor (TF)-DNA binding loci are explored by analyzing massive datasets generated with application of Chromatin Immuno-Precipitation (ChIP)-based high-throughput sequencing technologies. These datasets suffer from a bias in the information about binding loci availability, sample incompleteness and diverse sources of technical and biological noises. Therefore adequate mathematical models of ChIP-based high-throughput assay(s) and statistical tools are required for a

  17. Photon absorptiometry

    SciTech Connect

    Velchik, M.G.

    1987-01-01

    Recently, there has been a renewed interest in the detection and treatment of osteoporosis. This paper is a review of the merits and limitations of the various noninvasive modalities currently available for the measurement of bone mineral density with special emphasis placed upon the nuclear medicine techniques of single-photon and dual-photon absorptiometry. The clinicians should come away with an understanding of the relative advantages and disadvantages of photon absorptiometry and its optimal clinical application. 49 references.

  18. Statistical approach based on 1D Voronoi tessellation as a tool for studying the randomness of fractional digits of some irrational numbers

    E-print Network

    M. Fanfoni; M. Tomellini

    2015-05-19

    An "experimental" study on the randomness of the fractional digits of $\\pi$, $e$ and $\\phi$ irrational numbers are presented. This is done by exploiting the $1D$ Poisson-Voronoi tessellation. We employed two approaches and in both cases, within the numerical error, no differences have been detected between the irrational fractional digits and an equivalent random sequence of digits. The number of tested digits is $1.6 \\times 10^7$ and $4 \\times 10^7$ for the first and second approach, respectively. Although not shown here, we investigated several irrational numbers and all of them have displayed a similar behavior.

  19. Emitters of $N$-photon bundles

    E-print Network

    C. Sánchez Muñoz; E. del Valle; A. González Tudela; S. Lichtmannecker; K. Müller; M. Kaniber; C. Tejedor; J. J. Finley; F. P. Laussy

    2013-10-10

    We propose a scheme based on the coherent excitation of a two-level system in a cavity to generate an ultrabright CW and focused source of quantum light that comes in groups (bundles) of $N$ photons, for an integer $N$ tunable with the frequency of the exciting laser. We define a new quantity, the \\emph{purity} of $N$-photon emission, to describe the percentage of photons emitted in bundles, thus bypassing the limitations of Glauber correlation functions. We focus on the case $1\\le N\\le3$ and show that close to 100% of two-photon emission and 90% of three-photon emission is within reach of state of the art cavity QED samples. The statistics of the bundles emission shows that various regimes---from $N$-photon lasing to $N$-photon guns---can be realized. This is evidenced through generalized correlation functions that extend the standard definitions to the multi-photon level.

  20. Photonic Crystal Devices for Quantum and Nanoscale Photonics

    NASA Astrophysics Data System (ADS)

    Vuckovic, Jelena

    2005-03-01

    Photonic crystal structures can be built to operate in two opposite regimes: one is a suppression of photon states inside the photonic band gap, and the other is a large enhancement of the density of photon states. Both regimes are of consequence to a number of applications in nanoscale and nonlinear optics, as well as to photonic quantum information technologies. Our work on the employment of photonic crystals to build hardware of solid-state photonic quantum information systems, as well as to construct miniaturized optical devices will be reviewed in this talk. We have demonstrated sources of single photons on demand based on quantum dots in micropost microcavities that exhibit a large spontaneous emission rate enhancement (Purcell factor of five) together with a small multi-photon probability (2% compared to a Poisson-distributed source of the same intensity). We have also tested the indistinguishability of emitted single photons from such a source through a Hong-Ou-Mandel-type two-photon interference experiment, and found that consecutive photons exhibit a mean wave-packet overlap as large as 0.81, making this source useful in a variety of experiments in quantum optics and quantum information. The applications of such a device include secure quantum cryptography and linear optical quantum computation. We have also developed two-dimensional photonic crystal microcavities of finite depth with embedded quantum dots that exhibit large quality factors (˜3000) together with small mode volumes (˜0.5(?/n)^3) and with a maximum field intensity in the high-index region, which is of importance for enhanced interaction with quantum dot excitons. We have performed spectroscopy on a single quantum dot coupled to such a cavity, and demonstrated a very strong modification of its radiative properties, as well as a single-photon generation on demand. A strong interaction between a quantum dot exciton and the field enabled by such a microcavity is of importance for construction of single photon sources with improved efficiency, visibility, and speed, as well as for construction of entangled photon sources. Finally, we will also discuss some of our ongoing work on the integration of many photonic crystal components into functional circuits and devices, such as two-dimensional coupled arrays of photonic crystal microcavities for miniaturized lasers or sensors, or integration of photonic crystal cavities and waveguides for quantum networking.

  1. Photon emission in deep submicron SOI MOSFETs

    Microsoft Academic Search

    S.-H. Renn; J.-L. Pelloie; F. Balestra

    1996-01-01

    Hot carrier effects are thoroughly investigated in deep submiron N-and P-channel SOI MOSFETs using photon emission measurements. A substantial enhancement of the emitted photon number is observed with increasing the drain bias in the low gate voltage range, showing the impact of the parasitic bipolar transistor action (PBT). For Vg close to zero, a significant increase of the photon emission

  2. Magnetic monopole is photon

    E-print Network

    Sze Kui Ng

    2011-02-28

    It is shown that a photon with a specific frequency can be identified with the Dirac magnetic monopole. When a Dirac-Wilson line forms a Dirac-Wilson loop, it is a photon. This loop model of photon is exactly solvable. From the winding numbers of this loop-form of photon, we derive the quantization properties of energy and electric charge. A new QED theory is presented that is free of ultraviolet divergences. The Dirac-Wilson line is as the quantum photon propagator of the new QED theory from which we can derive known QED effects such as the anomalous magnetic moment and the Lamb shift. The one-loop computation of these effects is simpler and is more accurate than that in the conventional QED theory. Furthermore, from the new QED theory, we have derived a new QED effect. A new formulation of the Bethe-Salpeter (BS) equation solves the difficulties of the BS equation and gives a modified ground state of the positronium. By the mentioned new QED effect and by the new formulation of the BS equation, a term in the orthopositronium decay rate that is missing in the conventional QED is found, resolving the orthopositronium lifetime puzzle completely. It is also shown that the graviton can be constructed from the photon, yielding a theory of quantum gravity that unifies gravitation and electromagnetism.

  3. Spectral x-ray diffraction using a 6 megapixel photon counting array detector

    NASA Astrophysics Data System (ADS)

    Muir, Ryan D.; Pogranichniy, Nicholas R.; Muir, J. Lewis; Sullivan, Shane Z.; Battaile, Kevin P.; Mulichak, Anne M.; Toth, Scott J.; Keefe, Lisa J.; Simpson, Garth J.

    2015-03-01

    Pixel-array array detectors allow single-photon counting to be performed on a massively parallel scale, with several million counting circuits and detectors in the array. Because the number of photoelectrons produced at the detector surface depends on the photon energy, these detectors offer the possibility of spectral imaging. In this work, a statistical model of the instrument response is used to calibrate the detector on a per-pixel basis. In turn, the calibrated sensor was used to perform separation of dual-energy diffraction measurements into two monochromatic images. Targeting applications include multi-wavelength diffraction to aid in protein structure determination and X-ray diffraction imaging.

  4. On Realization of a Cavity-QED Laser Emitting a Highly Sub-Poissonian, Anti-Bunched Beam of Photons in a CW Fashion

    NASA Astrophysics Data System (ADS)

    Chough, Young-Tak

    2014-05-01

    We propose a feedback scheme to control the photon statistics in a micromaser/laser cavity, using the system output as the control signal, which generates a highly nonclassical field whose Mandel-Q parameter is even lower than ?0.9 and mean photon number much greater than unity. We demonstrate that the so-obtained system constitutes a continuous-wave (CW) quasi-Fock state source, the emission of which exhibits a sub-Poissonian photocount distribution as well as the photon anti-bunching property.

  5. Silicon Photonics

    Microsoft Academic Search

    Bahram Jalali; Sasan Fathpour

    2006-01-01

    After dominating the electronics industry for decades, silicon is on the verge of becoming the material of choice for the photonics industry: the traditional stronghold of III-V semiconductors. Stimulated by a series of recent breakthroughs and propelled by increasing investments by governments and the private sector, silicon photonics is now the most active discipline within the field of integrated optics.

  6. PHOTON2

    NSDL National Science Digital Library

    Funded through a three-year grant from the Advanced Technological Education (ATE) program of the National Science Foundation (NSF), Project PHOTON2 builds on the highly successful "Alliance" model developed through the previous Project PHOTON.In both projects, educators from several geographic locations (four to six regions nationally) are brought together to facilitate photonics technology education at their institutions that is intelligently developed and seamlessly articulated. The â??Alliancesâ? consist of four to six participants per region, including high school and two- and four-year college science, technology, engineering, and math instructors, as well as their institution's career and admissions counselors. On this site, visitors will find curriculum materials, information about the PHOTON2 laboratory kit and careers in photonics, links to external tutorials and applets, and societies and organizations. Visitors can also find out more about the project, its team, newsletter, conference papers, workshop, and a distance learning course for educators.

  7. Single-photon detection and its applications

    NASA Astrophysics Data System (ADS)

    Liang, Yan; Zeng, HePing

    2014-07-01

    A single-photon detector is an extremely sensitive device capable of registering photons, offering essential technical support for optics quantum information applications. We review herein our recent experimental progress in the development and application of single-photon detection techniques. Techniques based on advanced self-differencing, low-pass filtering, frequency up-conversion and photon-number-resolving are introduced for attaining high-speed, high-efficiency, low-noise single-photon detection at infrared wavelengths. The advantages of high-speed single-photon detection are discussed in some applications, such as the laser ranging and quantum key distribution. The photon-number-resolving detection is shown to support efficient quantum random number generation.

  8. Single-photon filtering by a cavity quantum electrodynamics system

    SciTech Connect

    Koshino, Kazuki [College of Liberal Arts and Sciences, Tokyo Medical and Dental University, 2-8-30 Konodai, Ichikawa 272-0827 (Japan) and PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012 (Japan)

    2008-02-15

    The nonlinear dynamics of a classical photon pulse in a cavity-QED system is investigated theoretically. It is shown that this system can work as a single-photon filter, which drastically suppresses the multiple-photon probability of the output. The output photon statistics is sensitive to the input pulse length. A suitable choice of pulse length produces a photon pulse with the single-photon probability of 0.32, while the multiple-photon probability is suppressed to 0.01.

  9. Single-Photon-Sensitive HgCdTe Avalanche Photodiode Detector

    NASA Technical Reports Server (NTRS)

    Huntington, Andrew

    2013-01-01

    The purpose of this program was to develop single-photon-sensitive short-wavelength infrared (SWIR) and mid-wavelength infrared (MWIR) avalanche photodiode (APD) receivers based on linear-mode HgCdTe APDs, for application by NASA in light detection and ranging (lidar) sensors. Linear-mode photon-counting APDs are desired for lidar because they have a shorter pixel dead time than Geiger APDs, and can detect sequential pulse returns from multiple objects that are closely spaced in range. Linear-mode APDs can also measure photon number, which Geiger APDs cannot, adding an extra dimension to lidar scene data for multi-photon returns. High-gain APDs with low multiplication noise are required for efficient linear-mode detection of single photons because of APD gain statistics -- a low-excess-noise APD will generate detectible current pulses from single photon input at a much higher rate of occurrence than will a noisy APD operated at the same average gain. MWIR and LWIR electron-avalanche HgCdTe APDs have been shown to operate in linear mode at high average avalanche gain (M > 1000) without excess multiplication noise (F = 1), and are therefore very good candidates for linear-mode photon counting. However, detectors fashioned from these narrow-bandgap alloys require aggressive cooling to control thermal dark current. Wider-bandgap SWIR HgCdTe APDs were investigated in this program as a strategy to reduce detector cooling requirements.

  10. Photonic crystal devices for photonic integrated circuits

    Microsoft Academic Search

    Min-Hsiung Shih

    2006-01-01

    Photonic crystal devices are potential candidates for chip-scale, dense photonic integrated circuits because photonic crystal devices have versatile optical characteristics and compact size. This thesis presents works to understand the properties of isolated photonic crystal elements before implement photonic integrated circuits with these individual elements as components. In this thesis, a brief introduction for photonic crystals will be followed by

  11. Statistical Laboratory & Department of Statistics

    E-print Network

    Statistical Laboratory & Department of Statistics Annual Report July 1, 2005 to December 31, 2006...............................................33 Statistical Computing Section ......................................34 CSSM and statistical methodology in the nutritional sciences. We were also very pleased to secure a permanent lecturer

  12. Resonant photonic States in coupled heterostructure photonic crystal waveguides.

    PubMed

    Cox, Jd; Sabarinathan, J; Singh, Mr

    2010-01-01

    In this paper, we study the photonic resonance states and transmission spectra of coupled waveguides made from heterostructure photonic crystals. We consider photonic crystal waveguides made from three photonic crystals A, B and C, where the waveguide heterostructure is denoted as B/A/C/A/B. Due to the band structure engineering, light is confined within crystal A, which thus act as waveguides. Here, photonic crystal C is taken as a nonlinear photonic crystal, which has a band gap that may be modified by applying a pump laser. We have found that the number of bound states within the waveguides depends on the width and well depth of photonic crystal A. It has also been found that when both waveguides are far away from each other, the energies of bound photons in each of the waveguides are degenerate. However, when they are brought close to each other, the degeneracy of the bound states is removed due to the coupling between them, which causes these states to split into pairs. We have also investigated the effect of the pump field on photonic crystal C. We have shown that by applying a pump field, the system may be switched between a double waveguide to a single waveguide, which effectively turns on or off the coupling between degenerate states. This reveals interesting results that can be applied to develop new types of nanophotonic devices such as nano-switches and nano-transistors. PMID:20672066

  13. Increasing number and incidence of low-trauma ankle fractures in elderly people: finnish statistics during 1970–2000 and projections for the future

    Microsoft Academic Search

    P Kannus; M Palvanen; S Niemi; J Parkkari; M Jrvinen

    2002-01-01

    To increase knowledge about recent trends in the number and incidence of various low-trauma injuries among elderly people, we selected, from the National Hospital Discharge Register, all patients ?60 years of age who were admitted to hospitals in Finland (5 million population) for primary treatment of a first low-trauma ankle fracture during 1970–2000. In each year of the study, the

  14. Selective photon counter for digital x-ray mammography tomosynthesis

    Microsoft Academic Search

    Amir H. Goldan; Karim S. Karim; J. A. Rowlands

    2006-01-01

    Photon counting is an emerging detection technique that is promising for mammography tomosynthesis imagers. In photon counting systems, the value of each image pixel is equal to the number of photons that interact with the detector. In this research, we introduce the design and implementation of a low noise, novel selective photon counting pixel for digital mammography tomosynthesis in crystalline

  15. Single photon counter for digital x-ray mammography tomosynthesis

    Microsoft Academic Search

    Amir H. Goldan; Karim S. Karim; John A. Rowlands

    2006-01-01

    Photon counting is an emerging detection technique that is promising for mammography tomosynthesis imagers. In photon counting systems, the value of each image pixel is equal to the number of photons that interact with the detector. In this research, we introduce the design and implementation of a low noise, photon counting pixel for digital mammography tomosynthesis in 0.18 μm crystalline

  16. NON-Shor Factorization Via BEQS BEC: Watkins Number-Theory ``Pure''-Mathematics U With Statistical-Physics; Benford Log-Law Inversion to ONLY BEQS digit d=0 BEC!!!

    NASA Astrophysics Data System (ADS)

    Lyons, M.; Siegel, Edward Carl-Ludwig

    2011-03-01

    Weiss-Page-Holthaus[Physica A,341,586(04); http://arxiv.org/abs/cond-mat/0403295] number-FACTORIZATION VIA BEQS BEC VS.(?) Shor-algorithm, strongly-supporting Watkins' [www.secamlocal.ex.ac.uk/people/staff/mrwatkin/] Intersection of number-theory "pure"-maths WITH (Statistical)-Physics, as Siegel[AMS Joint.Mtg.(02)-Abs.973-60-124] Benford logarithmic-law algebraic-INVERSION to ONLY BEQS with d=0 digit P (d = 0) > = oogapFULBEC ! ! ! SiegelRiemann - hypothesisproofviaRayleigh [ Phil . Trans . CLXI (1870) ] - Polya [ Math . Ann . (21) ] - [ Random - WalksElectric - Nets . , MAA (81) ] - nderson [ PRL (58) ] - localization - Siegel [ Symp . Fractals , MRSFallMtg . (89) - 5 - papers ! ! ! ] FUZZYICS = CATEGORYICS : [ LOCALITY ]- MORPHISM / CROSSOVER / AUTMATHCAT / DIM - CAT / ANTONYM- > (GLOBALITY) FUNCTOR / SYNONYM / concomitancetonoise = / Fluct . - Dissip . theorem / FUNCTOR / SYNONYM / equivalence / proportionalityto = > generalized - susceptibilitypower - spectrum [ FLAT / FUNCTIONLESS / WHITE ]- MORPHISM / CROSSOVER / AUTMATHCAT / DIM - CAT / ANTONYM- > HYPERBOLICITY/ZIPF-law INEVITABILITY) intersection with ONLY BEQS BEC).

  17. Statistical Issues in Searches: Photon Science Response

    E-print Network

    Masci, Frank

    (Similar oracle inequalities exist without the codelength perspective.) This framework leads to guarantees sparsity 5 / 34 #12;An oracle inequality1 Theorem If y Poisson(f), where f 1 = I, and f arg min fF {- logF f I - f I 2 2 approximation error + (f) I estimation error (Similar oracle inequalities exist

  18. First measurement of the quark-to-photon fragmentation function

    Microsoft Academic Search

    D. Casper; D. Decamp; P. Ghez; C. Goy; A. Lucotte; N. Minard; P. Odier; B. Pietrzyk; F. Ariztizabal; M. Chmeissani; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; V. Gaitan; M. Martinez; S. Orteu; A. Pacheco; C. Padilla; F. Palla; A. Pascual; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; A. Farilla; G. Gelao; M. Girone; G. Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Natali; S. Nuzzo; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; G. Bonvicini; M. Cattaneo; P. Comas; P. Coyle; H. Drevermann; A. Engelhardt; M. Frank; R. Hagelberg; J. Harvey; R. Jacobsen; P. Janot; B. Jost; J. Knobloch; I. Lehraus; C. Markou; P. Mato; H. Meinhard; A. Minten; R. Miquel; T. Oest; P. Palazzi; F. Ranjard; P. Rensing; L. Rolandi; D. Schlatter; M. Schmelling; O. Schneider; W. Tejessy; A. Venturi; H. Wachsmuth; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack

    1996-01-01

    Earlier measurements at LEP of isolated hard photons in hadronic Z decays, attributed to radiation from primary quark pairs, have been extended in the ALEPH experiment to include hard photon production inside hadron jets. Events are selected where all particles combine democratically to form hadron jets, one of which contains a photon with a fractional energy $z\\\\geq 0.7$. After statistical

  19. Broad flattop transparent photonic band in truncated photonic crystals composed of the symmetric unit cell

    Microsoft Academic Search

    Guiqiang Du; Lixin Li; Haitao Jiang; Yunhui Li; Liwei Zhang; Junfang Zhao; Tianlin Yang; Zhongchen Wu; Shumei Song; Yanhui Li; Maoshui Lv

    2010-01-01

    We theoretically show that a one-dimensional finite all-dielectric periodic structure composed of symmetric unit cells can possess a broad flattop transparent photonic band. In contrast to the conventional viewpoint that the thickness of the truncated photonic crystals affects the transmission within the pass band, the transparent photonic band is insensitive to the change of the periodic number since the equivalent

  20. Missing Children, Misleading Statistics.

    ERIC Educational Resources Information Center

    Best, Joel

    1988-01-01

    Examines the importance of defining terms in the process of gathering statistical data. Cites the example of the debate over the number of children abducted by strangers. Concludes that statistics are part of the persuasive rhetoric of social problem promotion and have social consequences. (FMW)

  1. Deconstructing Statistical Analysis

    ERIC Educational Resources Information Center

    Snell, Joel

    2014-01-01

    Using a very complex statistical analysis and research method for the sake of enhancing the prestige of an article or making a new product or service legitimate needs to be monitored and questioned for accuracy. 1) The more complicated the statistical analysis, and research the fewer the number of learned readers can understand it. This adds a…

  2. GRB 110709A, 111117A, AND 120107A: FAINT HIGH-ENERGY GAMMA-RAY PHOTON EMISSION FROM FERMI-LAT OBSERVATIONS AND DEMOGRAPHIC IMPLICATIONS

    SciTech Connect

    Zheng Weikang; Akerlof, Carl W.; McKay, Timothy A. [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109 (United States); Pandey, Shashi B. [Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital 263129 (India); Zhang Binbin [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Zhang Bing [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States); Sakamoto, Takanori, E-mail: zwk@umich.edu [Center for Research and Exploration in Space Science and Technology (CRESST), NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2012-09-01

    Launched on 2008 June 11, the Large Area Telescope (LAT) instrument on board the Fermi Gamma-ray Space Telescope has provided a rare opportunity to study high-energy photon emission from gamma-ray bursts (GRBs). Although the majority of such events (27) have been identified by the Fermi-LAT Collaboration, four were uncovered by using more sensitive statistical techniques. In this paper, we continue our earlier work by finding three more GRBs associated with high-energy photon emission, GRB 110709A, 111117A, and 120107A. To systematize our matched filter approach, a pipeline has been developed to identify these objects in nearly real time. GRB 120107A is the first product of this analysis procedure. Despite the reduced threshold for identification, the number of GRB events has not increased significantly. This relative dearth of events with low photon number prompted a study of the apparent photon number distribution. We find an extremely good fit to a simple power law with an exponent of -1.8 {+-} 0.3 for the differential distribution. As might be expected, there is a substantial correlation between the number of lower energy photons detected by the Gamma-ray Burst Monitor (GBM) and the number observed by LAT. Thus, high-energy photon emission is associated with some but not all of the brighter GBM events. Deeper studies of the properties of the small population of high-energy emitting bursts may eventually yield a better understanding of these entire phenomena.

  3. Two-photon-induced fluorescence.

    PubMed

    Callis, P R

    1997-01-01

    Nonresonant two-photon electronic spectroscopy of polyatomic molecules is reviewed for the period since 1979. Emphasis is placed on studies that expose patterns in the two-photon fluorescence (also ionization, optoacoustic) excitation spectra of aromatic hydrocarbons and the effect of vibrations and substitution, particularly within the framework of pseudoparity rules. A section is devoted to biological molecules and the emerging use of two-photon-induced fluorescence anisotropy. Relevant theoretical results are discussed, with emphasis on quantum chemical predictions of vibronic coupling and substituent effects on two-photon absorptivity and tensor properties of individual molecules. This chapter includes higher-order spectroscopy, and a limited number of three- and four-photon studies are discussed. PMID:15012446

  4. December 2000 A STATISTICAL TEST

    E-print Network

    December 2000 A STATISTICAL TEST SUITE FOR RANDOM AND PSEUDORANDOM NUMBER GENERATORS challenges in authentication protocols. NIST Special Publication (SP) 800-22, A Statistical Test Suite testing of random number and pseudorandom number generators (RNGs and PRNGs) that may be used for many

  5. Adoption Statistics

    MedlinePLUS

    ... is not valid, please reenter the captcha code Statistics All statistics correspond with the U.S. Government fiscal year, which ... and ends on September 30. For example, adoption statistics for FY2014 show the period from October 1, ...

  6. Green photonics: the role of photonics in sustainable product design

    NASA Astrophysics Data System (ADS)

    Wessler, Berit; Tober, Ursula

    2011-05-01

    Photonic technologies will play an increasingly significant role in reducing our environmental impact. In addition to the direct eco-benefits derived from the products themselves, green photonics will also impact the product design and manufacturing processes employed. Examples are discussed covering laser manufacturing, solid-state lighting, solar cells and optical communications. The importance of considering the full lifetime environmental impact of products is discussed, including raw materials, manufacture, use, and end of life issues. Industrial and legislative strategies are reviewed, and a number of specific measures are presented for accelerating the development of green photonics technologies and promoting their adoption into society.

  7. 32. Statistics 1 32. STATISTICS

    E-print Network

    Masci, Frank

    32. Statistics 1 32. STATISTICS Revised September 2007 by G. Cowan (RHUL). This chapter gives an overview of statistical methods used in High Energy Physics. In statistics, we are interested in using's validity or to determine the values of its parameters. There are two main approaches to statistical

  8. Department of Statistics STATISTICS COLLOQUIUM

    E-print Network

    Department of Statistics STATISTICS COLLOQUIUM ERIC KOLACZYK Department of Statistics Boston University Statistical Analysis of Network Data: (Re)visiting the Foundations MONDAY, October 13, 2014, at 4, statistical methods and modeling have been central to these efforts. But how well do we truly understand

  9. Opportunities for single-photon detection using visible light photon counters

    Microsoft Academic Search

    Jungsang Kim; Kyle S. McKay; Maryn G. Stapelbroek; Henry H. Hogue

    2011-01-01

    Visible light photon counters (VLPCs) are solid-state devices providing high quantum efficiency (QE) photon detection (>88%) with photon number resolving capability and low timing jitter (~250 ps). VLPC features high QE in the 0.4-1.0mum wavelength range, as the main photon absorption mechanism is provided by electron-hole pair generation across the silicon bandgap. In this paper, we will discuss the optical

  10. Polarization-Entangled Light Pulses of 10^5 Photons

    E-print Network

    Timur Sh. Iskhakov; Ivan N. Agafonov; Maria V. Chekhova; Gerd Leuchs

    2012-06-18

    We experimentally demonstrate polarization entanglement for squeezed vacuum pulses containing more than 10^5 photons. We also study photon-number entanglement by calculating the Schmidt number and measuring its operational counterpart. Theoretically, our pulses are the more entangled the brighter they are. This promises important applications in quantum technologies, especially photonic quantum gates and quantum memories.

  11. Development of Magnetic Materials for Photonic Applications

    NASA Astrophysics Data System (ADS)

    Baert, Kasper; Libaers, Wim; Kolaric, Branko; Vallée, Renaud A. L.; van der Auweraer, Mark; Clays, Koen; Grandjean, Didier; di Vece, Marcel; Lievens, Peter

    In this manuscript, the synthesis and characterization of superparamagnetic particles and their silica-coated counterparts as building blocks for magnetic photonic crystals is fully described. The advantages and disadvantages of the presented synthetic method are discussed. Preliminary results considering the presence of magnetic species within a photonic crystal are also presented. Suppression of emission of the quantum dots within photonic crystals is attributed to a decrease of the number of available photonic modes for radiative decay. The presence of materials with permanent magnetic moments within photonic crystals shows that suppression of their emission is scaled with the strength of the magnetic field.

  12. Engineered quantum dot single-photon sources

    NASA Astrophysics Data System (ADS)

    Buckley, Sonia; Rivoire, Kelley; Vu?kovi?, Jelena

    2012-12-01

    Fast, high efficiency and low error single-photon sources are required for the implementation of a number of quantum information processing applications. The fastest triggered single-photon sources to date have been demonstrated using epitaxially grown semiconductor quantum dots (QDs), which can be conveniently integrated with optical microcavities. Recent advances in QD technology, including demonstrations of high temperature and telecommunications wavelength single-photon emission, have made QD single-photon sources more practical. Here we discuss the applications of single-photon sources and their various requirements, before reviewing the progress made on a QD platform in meeting these requirements.

  13. Photon doses in NPL standard neutron fields.

    PubMed

    Roberts, N J; Horwood, N A; McKay, C J

    2014-10-01

    Standard neutron fields are invariably accompanied by a photon component due to the neutron-generating reactions and secondary neutron interactions in the surrounding environment. A set of energy-compensated Geiger-Müller (GM) tubes and electronic personal dosemeters (EPDs) have been used to measure the photon dose rates in a number of standard radionuclide and accelerator-based neutron fields. The GM tubes were first characterised in standard radioisotope and X-ray photon fields and then modelled using MCNP to determine their photon dose response as a function of energy. Values for the photon-to-neutron dose equivalent ratios are presented and compared with other published values. PMID:24126485

  14. Single photon interference Single photon interference

    E-print Network

    Spagnolo, Filippo

    Single photon interference Single photon interference with a Fresnel biprism Contacts: Jean-François Roch François Treussart Philippe Grangier Introduction Single photon source Interference fringes Anticorrelation Archives Single-photon interference Single photons emitted by the N-V colour centre are sent

  15. Laser diodes in photon number squeezed state

    Microsoft Academic Search

    Syoichi Kakimoto; Kimio Shigihara; Yutaka Nagai

    1997-01-01

    A laser diode with an intrinsic layer as the space charge limited current region is expected to emit a low noise (less than the shot noise level) light. However, when one applies the intrinsic layer to the laser diode, severe difficulty is faced. Because the intrinsic layer has a very high resistivity, the applied voltage to operate the laser diode

  16. Photon counting and fast photometry with L3 CCDs

    NASA Astrophysics Data System (ADS)

    Tulloch, Simon M.

    2004-09-01

    The new L3 Technology CCDs from E2V allow detector read noise to be decoupled from readout speed. If operated at sufficiently high gain, the read noise drops to sub-electron levels and photon counting becomes possible. At ING we have incorporated CCD60 , CCD87 and CCD97 L3 detectors into cryogenic cameras coupled to SDSU controllers for a variety of tests both in the lab and on-sky using the 4.2m William Herschel Telescope. These detectors have been operated in proportional and photon-counting mode using an in-house Linux based DAS. We have gained a number of insights into photon counting optimisation, how to cope with the effects of the L3 pipeline delay and the reduction of internal device-generated spurious charge. We have also discovered a statistical method for determining the gain of an L3 system from pulse height analysis of the individual photon events. Our on-sky test program has consisted to date of high frame rate photometry of the Crab Nebula Pulsar.

  17. Single photon detection and timing - Experiments and techniques.

    NASA Technical Reports Server (NTRS)

    Poultney, S. K.

    1972-01-01

    Single photon detection and timing means essentially the detection and timing of a single photoelectron released by light from a photosensitive surface of a photomultiplier, channel multiplier, avalanche multiplier photodiode, or other photodevice. Necessary photodevice gain and detection circuits, mechanisms and statistics of photodevice gain, photodevice and background noise and their reduction, and practical photodevice techniques and photon detection performance tests are discussed. Fast timing with single photons, and single photon detection with moderate timing requirements are considered.

  18. Multi-element superconducting nanowire single photon detectors

    E-print Network

    Dauler, Eric A. (Eric Anthony), 1980-

    2009-01-01

    Single-photon-detector arrays can provide unparalleled performance and detailed information in applications that require precise timing and single photon sensitivity. Such arrays have been demonstrated using a number of ...

  19. Di-photon and photon + b/c production cross sections at Ecm = 1.96- TeV

    SciTech Connect

    Gajjar, Anant; /Liverpool U.

    2005-05-01

    Measurements of the di-photon cross section have been made in the central region and are found to be in good agreement with NLO QCD predictions. The cross section of events containing a photon and additional heavy flavor jet have also been measured, as well as the ratio of photon + b to photon + c. The statistically limited sample shows good agreement with Leading Order predictions.

  20. Generalized quantum interference of correlated photon pairs

    E-print Network

    Heonoh Kim; Sang Min Lee; Han Seb Moon

    2015-03-30

    Superposition and indistinguishablility between probability amplitudes have played an essential role in observing quantum interference effects of correlated photons. The Hong-Ou-Mandel interference and interferences of the path-entangled photon number state are of special interest in the field of quantum information technologies. However, a fully generalized two-photon quantum interferometric scheme accounting for the Hong-Ou-Mandel scheme and path-entangled photon number states has not yet been proposed. Here we report the experimental demonstrations of the generalized two-photon interferometry with both the interferometric properties of the Hong-Ou-Mandel effect and the fully unfolded version of the path-entangled photon number state using photon-pair sources, which are independently generated by spontaneous parametric down-conversion. Our experimental scheme explains two-photon interference fringes revealing single- and two-photon coherence properties in a single interferometer setup. Using the proposed interferometric measurement, it is possible to directly estimate the joint spectral intensity of a photon pair source.

  1. Statistics on pattern-avoiding permutations

    E-print Network

    Elizalde, Sergi, 1979-

    2004-01-01

    This thesis concerns the enumeration of pattern-avoiding permutations with respect to certain statistics. Our first result is that the joint distribution of the pair of statistics 'number of fixed points' and 'number of ...

  2. Frozen photons in Jaynes Cummings arrays

    E-print Network

    N. Schetakis; T. Grujic; S. R. Clark; D. Jaksch; D. G. Angelakis

    2013-06-02

    We study the origin of "frozen" states in coupled Jaynes-Cummings-Hubbard arrays in the presence of losses. For the case of half the array initially populated with photons while the other half is left empty we show the emergence of self-localized photon or "frozen" states for specific values of the local atom-photon coupling. We analyze the dynamics in the quantum regime and discover important additional features appear not captured by a semiclassical treatment, which we analyze for different array sizes and filling fractions. We trace the origin of this interaction-induced photon "freezing" to the suppression of excitation of propagating modes in the system at large interaction strengths. We discuss in detail the possibility to experimentally probe the relevant transition by analyzing the emitted photon correlations. We find a strong signature of the effect in the emitted photons statistics.

  3. Emitters of N-photon bundles

    PubMed Central

    Muñoz, C. Sánchez; del Valle, E.; Tudela, A. González; Müller, K.; Lichtmannecker, S.; Kaniber, M.; Tejedor, C.; Finley, J.J.; Laussy, F.P.

    2014-01-01

    Controlling the ouput of a light emitter is one of the basic tasks of photonics, with landmarks such as the laser and single-photon sources. The development of quantum applications makes it increasingly important to diversify the available quantum sources. Here, we propose a cavity QED scheme to realize emitters that release their energy in groups, or “bundles” of N photons, for integer N. Close to 100% of two-photon emission and 90% of three-photon emission is shown to be within reach of state of the art samples. The emission can be tuned with system parameters so that the device behaves as a laser or as a N-photon gun. The theoretical formalism to characterize such emitters is developed, with the bundle statistics arising as an extension of the fundamental correlation functions of quantum optics. These emitters will be useful for quantum information processing and for medical applications. PMID:25013456

  4. Photon collider at TESLA

    E-print Network

    Valery Telnov

    2001-03-06

    High energy photon colliders (gamma-gamma, gamma-electron) based on backward Compton scattering of laser light is a very natural addition to e+e- linear colliders. In this report we consider this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case the gamma-gamma luminosity luminosity in the high energy part of spectrum can reach (1/3)L_{e+e-}. Typical cross sections of interesting processes in gamma-gamma collisions are higher than those in e+e- collisions by about one order of magnitude, so the number of events in gamma-gamma collisions will be more than that in e+e- collisions. Photon colliders can, certainly, give additional information and they are the best for the study of many phenomena. The main question is now the technical feasibility. The key new element in photon colliders is a very powerful laser system. An external optical cavity is a promising approach for the TESLA project. A free electron laser is another option. However, a more straightforward solution is ``an optical storage ring (optical trap)'' with diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters and existing problems.

  5. Integrated spatial multiplexing of heralded single-photon sources

    PubMed Central

    Collins, M.J.; Xiong, C.; Rey, I.H.; Vo, T.D.; He, J.; Shahnia, S.; Reardon, C.; Krauss, T.F.; Steel, M.J.; Clark, A.S.; Eggleton, B.J.

    2013-01-01

    The non-deterministic nature of photon sources is a key limitation for single-photon quantum processors. Spatial multiplexing overcomes this by enhancing the heralded single-photon yield without enhancing the output noise. Here the intrinsic statistical limit of an individual source is surpassed by spatially multiplexing two monolithic silicon-based correlated photon pair sources in the telecommunications band, demonstrating a 62.4% increase in the heralded single-photon output without an increase in unwanted multipair generation. We further demonstrate the scalability of this scheme by multiplexing photons generated in two waveguides pumped via an integrated coupler with a 63.1% increase in the heralded photon rate. This demonstration paves the way for a scalable architecture for multiplexing many photon sources in a compact integrated platform and achieving efficient two-photon interference, required at the core of optical quantum computing and quantum communication protocols. PMID:24107840

  6. Waveguide single-photon detectors for integrated quantum photonic circuits

    E-print Network

    J. P. Sprengers; A. Gaggero; D. Sahin; S. Jahanmiri Nejad; F. Mattioli; R. Leoni; J. Beetz; M. Lermer; M. Kamp; S. Höfling; R. Sanjines; A. Fiore

    2011-08-25

    The generation, manipulation and detection of quantum bits (qubits) encoded on single photons is at the heart of quantum communication and optical quantum information processing. The combination of single-photon sources, passive optical circuits and single-photon detectors enables quantum repeaters and qubit amplifiers, and also forms the basis of all-optical quantum gates and of linear-optics quantum computing. However, the monolithic integration of sources, waveguides and detectors on the same chip, as needed for scaling to meaningful number of qubits, is very challenging, and previous work on quantum photonic circuits has used external sources and detectors. Here we propose an approach to a fully-integrated quantum photonic circuit on a semiconductor chip, and demonstrate a key component of such circuit, a waveguide single-photon detector. Our detectors, based on superconducting nanowires on GaAs ridge waveguides, provide high efficiency (20%) at telecom wavelengths, high timing accuracy (60 ps), response time in the ns range, and are fully compatible with the integration of single-photon sources, passive networks and modulators.

  7. Using high-power lasers for detection of elastic photon-photon scattering

    E-print Network

    E. Lundstrom; G. Brodin; J. Lundin; M. Marklund; R. Bingham; J. Collier; J. T. Mendonca; P. Norreys

    2006-02-01

    The properties of four-wave interaction via the nonlinear quantum vacuum is investigated. The effect of the quantum vacuum is to generate photons with new frequencies and wave vectors, due to elastic photon-photon scattering. An expression for the number of generated photons is derived and using state-of-the-art laser data it is found that the number of photons can reach detectable levels. In particular, the prospect of using the high repetition Astra Gemini system at the Rutherford Appleton Laboratory is discussed. The problem of noise sources is reviewed, and it is found that the noise level can be reduced well below the signal level. Thus, detection of elastic photon-photon scattering may for the first time be achieved.

  8. Light scattering from ultracold atoms in optical lattices as an optical probe of quantum statistics

    E-print Network

    Igor B. Mekhov; Christoph Maschler; Helmut Ritsch

    2007-10-28

    We study off-resonant collective light scattering from ultracold atoms trapped in an optical lattice. Scattering from different atomic quantum states creates different quantum states of the scattered light, which can be distinguished by measurements of the spatial intensity distribution, quadrature variances, photon statistics, or spectral measurements. In particular, angle-resolved intensity measurements reflect global statistics of atoms (total number of radiating atoms) as well as local statistical quantities (single-site statistics even without an optical access to a single site) and pair correlations between different sites. As a striking example we consider scattering from transversally illuminated atoms into an optical cavity mode. For the Mott insulator state, similar to classical diffraction, the number of photons scattered into a cavity is zero due to destructive interference, while for the superfluid state it is nonzero and proportional to the number of atoms. Moreover, we demonstrate that light scattering into a standing-wave cavity has a nontrivial angle dependence, including the appearance of narrow features at angles, where classical diffraction predicts zero. The measurement procedure corresponds to the quantum non-demolition (QND) measurement of various atomic variables by observing light.

  9. A single-photon server with just one atom MARKUS HIJLKEMA1

    E-print Network

    Loss, Daniel

    the photon-emission statistics and, second, guarantee the subsequent performance as a single-photon server from the system are detected by two avalanche photodiodes in the Hanbury Brown and Twiss configuration.

  10. STATISTICS AND MODELING Unique Number: 04110

    E-print Network

    Ghosh, Joydeep

    analysis and forecasting. Prerequisites: Management Information Systems 301 or 310; Mathematics 408D, 408L. Grading Policy: The course grade is comprised of the following elements: Homework ­ 20% Four exams ­ 80% (20% per exam) There is no predetermined grade distribution for this class. The standard Mc

  11. STATISTICS AND MODELING Unique Numbers: 04605

    E-print Network

    Ghosh, Joydeep

    of the following elements: Homework ­ 20% Four exams ­ 80% (20% per exam) There is no predetermined grade in the decision making areas of business ­ accounting, finance, economics, marketing, and operations management linear and multiple regression, time series analysis and forecasting. Prerequisites Management

  12. Photon-aided and photon-inhibited tunneling of photons

    NASA Astrophysics Data System (ADS)

    Liu, Xuele; Agarwal, G. S.

    2013-06-01

    In light of the interest in the transport of single photons in arrays of waveguides, fiber couplers, photonic crystals, etc., we consider the quantum mechanical process of the tunneling of photons through evanescently or otherwise coupled structures. We specifically examine the issue of tunneling between two structures when one structure already contains few photons. We demonstrate the possibility of both photon-aided and photon-inhibited tunneling of photons. The bosonic nature of photons enhances the tunneling probability. We also show how the multiphoton tunneling probability can be either enhanced or inhibited due to the presence of photons. We find similar results for higher-order tunneling. Finally, we show that the presence of a squeezed field changes the nature of tunneling considerably.

  13. Caregiving Statistics

    MedlinePLUS

    Statistics on Family Caregivers and Family Caregiving Caregiving Population Economics of Caregiving Impact on Family Caregiver's Health ... Identified Family Caregivers, 2001. Top State by State Statistics The economic value of family caregiving is detailed ...

  14. Histoplasmosis Statistics

    MedlinePLUS

    ... About CDC.gov . Fungal Diseases Share Compartir Histoplasmosis Statistics How common is histoplasmosis? In the United States, ... Risk & Prevention Sources Diagnosis & Testing Treatment Health Professionals Statistics More Resources Blastomycosis Definition Symptoms People at Risk & ...

  15. Cancer Statistics

    MedlinePLUS

    ... success of efforts to control and manage cancer. Statistics at a Glance: The Burden of Cancer in ... 2010 and could reach $156 billion in 2020. Statistics at a Glance: The Burden of Cancer Worldwide ...

  16. Usage Statistics

    MedlinePLUS

    ... www.nlm.nih.gov/medlineplus/usestatistics.html MedlinePlus Statistics To use the sharing features on this page, ... By Quarter View image full size Quarterly User Statistics Quarter Page Views Unique Visitors Oct-Dec-98 ...

  17. Microalgae photonics

    NASA Astrophysics Data System (ADS)

    Floume, Timmy; Coquil, Thomas; Sylvestre, Julien

    2011-05-01

    Due to their metabolic flexibility and fast growth rate, microscopic aquatic phototrophs like algae have a potential to become industrial photochemical converters. Algae photosynthesis could enable the large scale production of clean and renewable liquid fuels and chemicals with major environmental, economic and societal benefits. Capital and operational costs are the main issues to address through optical, process and biochemical engineering improvements. In this perspective, a variety of photonic approaches have been proposed - we introduce them here and describe their potential, limitations and compatibility with separate biotechnology and engineering progresses. We show that only sunlight-based approaches are economically realistic. One of photonics' main goals in the algae field is to dilute light to overcome photosaturation effects that impact upon cultures exposed to full sunlight. Among other approaches, we introduce a widely-compatible broadband spectral adaptation technique called AlgoSun® that uses luminescence to optimize sunlight spectrum in view of the bioconverter's requirements.

  18. Exciton-photon correlations in bosonic condensates of exciton-polaritons

    PubMed Central

    Kavokin, Alexey V.; Sheremet, Alexandra S.; Shelykh, Ivan A.; Lagoudakis, Pavlos G.; Rubo, Yuri G.

    2015-01-01

    Exciton-polaritons are mixed light-matter quasiparticles. We have developed a statistical model describing stochastic exciton-photon transitions within a condensate of exciton polaritons. We show that the exciton-photon correlator depends on the rate of incoherent exciton-photon transformations in the condensate. We discuss implications of this effect for the quantum statistics of photons emitted by polariton lasers. PMID:26153979

  19. Exciton-photon correlations in bosonic condensates of exciton-polaritons.

    PubMed

    Kavokin, Alexey V; Sheremet, Alexandra S; Shelykh, Ivan A; Lagoudakis, Pavlos G; Rubo, Yuri G

    2015-01-01

    Exciton-polaritons are mixed light-matter quasiparticles. We have developed a statistical model describing stochastic exciton-photon transitions within a condensate of exciton polaritons. We show that the exciton-photon correlator depends on the rate of incoherent exciton-photon transformations in the condensate. We discuss implications of this effect for the quantum statistics of photons emitted by polariton lasers. PMID:26153979

  20. Statistical Diversions

    ERIC Educational Resources Information Center

    Petocz, Peter; Sowey, Eric

    2012-01-01

    The term "data snooping" refers to the practice of choosing which statistical analyses to apply to a set of data after having first looked at those data. Data snooping contradicts a fundamental precept of applied statistics, that the scheme of analysis is to be planned in advance. In this column, the authors shall elucidate the statistical…

  1. Better Randomness with Single Photons

    E-print Network

    Lukas Oberreiter; Ilja Gerhardt

    2014-11-13

    Randomness is one of the most important resources in modern information science, since encryption founds upon the trust in random numbers. Since it is impossible to prove if an existing random bit string is truly random, it is relevant that they be generated in a trust worthy process. This requires specialized hardware for random numbers, for example a die or a tossed coin. But when all input parameters are known, their outcome might still be predicted. A quantum mechanical superposition allows for provably true random bit generation. In the past decade many quantum random number generators (QRNGs) were realized. A photonic implementation is described as a photon which impinges on a beam splitter, but such a protocol is rarely realized with non-classical light or anti-bunched single photons. Instead, laser sources or light emitting diodes are used. Here we analyze the difference in generating a true random bit string with a laser and with anti-bunched light. We show that a single photon source provides more randomness than even a brighter laser. This gain of usable entropy proves the advantages of true single photons versus coherent input states of light in an experimental implementation. The underlying advantage can be adapted to microscopy and sensing.

  2. Law of Large Numbers

    NSDL National Science Digital Library

    Grinstead, Charles M.

    Created by Charles M. Grinstead and J. Laurie Snell of Dartmouth College, this website is part of an online statistics textbook. Topics include: (1) Law of Large Numbers for Discrete Random Variables, (2) Chebyshev Inequality, (3) Law of Averages, (4) Law of Large Numbers for Continuous Random Variables, (5) Monte Carlo Method. There are several examples and exercises that accompany the material.

  3. Term statistics Zipf's law text statistics

    E-print Network

    Lu, Jianguo

    Term statistics Zipf's law text statistics October 20, 2014 text statistics 1 / 19 #12;Term statistics Zipf's law Overview 1 Term statistics 2 Zipf's law text statistics 2 / 19 #12;Term statistics Zipf's law Outline 1 Term statistics 2 Zipf's law text statistics 3 / 19 #12;Term statistics Zipf's law Model

  4. General displaced SU(1, 1) number states: Revisited

    SciTech Connect

    Dehghani, A., E-mail: alireza.dehghani@gmail.com, E-mail: a-dehghani@tabrizu.ac.ir [Physics Department, Payame Noor University, P.O. Box 19395-3697 Tehran (Iran, Islamic Republic of)

    2014-04-15

    The most general displaced number states, based on the bosonic and an irreducible representation of the Lie algebra symmetry of su(1, 1) and associated with the Calogero-Sutherland model are introduced. Here, we utilize the Barut-Girardello displacement operator instead of the Klauder-Perelomov counterpart, to construct new kind of the displaced number states which can be classified in nonlinear coherent states regime, too, with special nonlinearity functions. They depend on two parameters, and can be converted into the well-known Barut-Girardello coherent and number states, respectively, depending on which of the parameters equal to zero. A discussion of the statistical properties of these states is included. Significant are their squeezing properties and anti-bunching effects which can be raised by increasing the energy quantum number. Depending on the particular choice of the parameters of the above scenario, we are able to determine the status of compliance with flexible statistics. Major parts of the issue is spent on something that these states, in fact, should be considered as new kind of photon-added coherent states, too. Which can be reproduced through an iterated action of a creation operator on new nonlinear Barut-Girardello coherent states. Where the latter carry, also, outstanding statistical features.

  5. UCLA Statistics Series

    NSDL National Science Digital Library

    The University of California Los Angeles Statistics Series presents a collection of more than 250 preprints covering a wide array of statistical topics, such as descriptive multivariate analysis, advanced linear models, survey construction and analysis, teaching statistics, and much more. The preprints are arranged by paper number only, hence users must browse the entire list to locate relevant items. Approximately half of the full-text preprints are accessible in HTML, .pdf, or postscript formats. To access preprints not available electronically, users must contact the authors of the papers; author addresses are provided.

  6. Multimode One-Way Waveguides of Large Chern Numbers

    E-print Network

    Skirlo, Scott A.

    Current experimental realizations of the quantum anomalous Hall phase in both electronic and photonic systems have been limited to a Chern number of one. In photonics, this corresponds to a single-mode one-way edge waveguide. ...

  7. Quantum teleportation using bipartite entangled photon-added non-linear coherent states

    NASA Astrophysics Data System (ADS)

    Castro, E.; Páez, E. J.; Ladera, C. L.; Zambrano, A.

    2013-11-01

    Quantum teleportation has attracted much attention from both theorists and experimenters in the last decade. The emergence of new protocols and their actual implementation have even motivated the development of new quantum optical schemes. A key issue when teleporting a quantum state is establishing the quantum channel between sender and receiver stations, usually done by manipulating an auxiliary bipartite entangled state. The purpose of the present work is to study quantum teleportation processes in which that state is an entangled bipartite photon-added state, and the Adhikari et. al. continuous-variable quantum teleportation protocol is applied. Photon-added states can be generated using different experimental techniques, such as parametric down-conversion in a nonlinear crystal, and conditioned parametric amplification. These states are relevant because they exhibit generalized non-classical features for all orders of creation and annihilation operators, and may even show phase squeezing and sub-Poissonian distribution statistics. We study, the dependence of the fidelity of the teleported states and their photon number statistic as a function of the higher-order squeezing, and the higher-order sub-Poissonian statistic.

  8. Quantum Imaging with Incoherent Photons

    Microsoft Academic Search

    C. Thiel; T. Bastin; J. Martin; E. Solano; J. von Zanthier; G. S. Agarwal

    2007-01-01

    We propose a technique to obtain subwavelength resolution in quantum imaging with potentially 100% contrast using incoherent light. Our method requires neither path-entangled number states nor multiphoton absorption. The scheme makes use of N photons spontaneously emitted by N atoms and registered by N detectors. It is shown that for coincident detection at particular detector positions a resolution of lambda\\/N

  9. Single photon searches at PEP

    SciTech Connect

    Hollebeek, R.

    1985-12-01

    The MAC and ASP searches for events with a single photon and no other observed particles are reviewed. New results on the number of neutrino generations and limits on selection, photino, squark and gluino masses from the ASP experiment are presented.

  10. Photon-counting techniques with silicon avalanche photodiodes

    Microsoft Academic Search

    Henri Dautet; Pierre Deschamps; Bruno Dion; Andrew D. MacGregor; Darleene MacSween; Robert J. McIntyre; Claude Trottier; Paul P. Webb

    1993-01-01

    Silicon avalanche photodiodes (APD) have been used for photon counting for a number of years. This paper reviews their properties and the associated electronics required for photon counting in the Geiger mode. Significant improvements are reported in overall photon detection efficiencies (approaching 75% at 633 nm), and timing jitter (under 200 ps) achieved at high over-voltages (20 - 30 V).

  11. Photonic Circuits for Generating Modal, Spectral, and Polarization Entanglement

    E-print Network

    Teich, Malvin C.

    Photonic Circuits for Generating Modal, Spectral, and Polarization Entanglement Volume 2, Number 5@creol.ucf.edu). Abstract: We consider the design of photonic circuits that make use of Ti:LiNbO3 diffused channel-mode waveguide (TMW). We study a class of photonic circuits comprising: 1) a nonlinear periodically poled TMW

  12. Jaynes Cummings Photonic Superlattices

    E-print Network

    Stefano Longhi

    2011-11-15

    A classical realization of the Jaynes-Cummings (JC) model, describing the interaction of a two-level atom with a quantized cavity mode, is proposed based on light transport in engineered waveguide superlattices. The optical setting enables to visualize in Fock space dynamical regimes not yet accessible in quantum systems, providing new physical insights into the deep strong coupling regime of the JC model. In particular, bouncing of photon number wave packets in Hilbert space and revivals of populations are explained as generalized Bloch oscillations in an inhomogeneous tight-binding lattice.

  13. High Accuracy Calibration of Photon-Counting Detectors Sergey V. Polyakov*a

    E-print Network

    Hart, Gus

    that appropriately handles complex properties of typical avalanche photodiode (APD) detectors. Also discussed an accurate calibration. Keywords: calibration, detector, down-conversion, correlated photons, statistical

  14. Di-photon production at the LHC

    SciTech Connect

    Dixon, Lance

    2003-06-18

    The standard model production of two photons is one of the most important backgrounds to light Higgs boson production at the LHC. In this talk we discuss the di-photon background, with emphasis on the effects of the recently calculated next-to-leading-order (NLO) corrections to the gluon-gluon-initiated component. We find that the K-factor for this component is smaller than that for the analogous gg {yields} H process, and that the correction to the total irreducible di-photon production is modest. We also investigate ways to enhance the statistical significance of the Higgs signal in the {gamma}{gamma} channel.

  15. Universal Characteristics of Fractal Fluctuations in Prime Number Distribution

    E-print Network

    A. M. Selvam

    2008-11-12

    The frequency of occurrence of prime numbers at unit number spacing intervals exhibits selfsimilar fractal fluctuations concomitant with inverse power law form for power spectrum generic to dynamical systems in nature such as fluid flows, stock market fluctuations, population dynamics, etc. The physics of long-range correlations exhibited by fractals is not yet identified. A recently developed general systems theory visualises the eddy continuum underlying fractals to result from the growth of large eddies as the integrated mean of enclosed small scale eddies, thereby generating a hierarchy of eddy circulations, or an inter-connected network with associated long-range correlations. The model predictions are as follows: (i) The probability distribution and power spectrum of fractals follow the same inverse power law which is a function of the golden mean. The predicted inverse power law distribution is very close to the statistical normal distribution for fluctuations within two standard deviations from the mean of the distribution. (ii) Fractals signify quantumlike chaos since variance spectrum represents probability density distribution, a characteristic of quantum systems such as electron or photon. (ii) Fractal fluctuations of frequency distribution of prime numbers signify spontaneous organisation of underlying continuum number field into the ordered pattern of the quasiperiodic Penrose tiling pattern. The model predictions are in agreement with the probability distributions and power spectra for different sets of frequency of occurrence of prime numbers at unit number interval for successive 1000 numbers. Prime numbers in the first 10 million numbers were used for the study.

  16. On-chip single photon emission from an integrated semiconductor quantum dot into a photonic crystal waveguide

    NASA Astrophysics Data System (ADS)

    Schwagmann, Andre; Kalliakos, Sokratis; Farrer, Ian; Griffiths, Jonathan P.; Jones, Geb A. C.; Ritchie, David A.; Shields, Andrew J.

    2011-12-01

    We demonstrate the in-plane emission of highly polarized single photons from an InAs quantum dot embedded into a photonic crystal waveguide. The spontaneous emission rates are Purcell-enhanced by the coupling of the quantum dot to a slow-light mode of the waveguide. Photon-correlation measurements confirm the sub-Poissonian statistics of the in-plane emission. Under optical pulse excitation, single photon emission rates of up to 19 MHz into the guided mode are demonstrated, which corresponds to a device efficiency of 24%. These results herald the monolithic integration of sources in photonic quantum circuits.

  17. Using single photons to improve fiber optic communication systems

    NASA Astrophysics Data System (ADS)

    Pinto, Armando N.; Silva, Nuno A.; Almeida, Álvaro J.; Muga, Nelson J.

    2014-08-01

    We show how to generate, encode, transmit and detect single photons. By using single photons we can address two of the more challenging problems that communication engineers face nowadays: capacity and security. Indeed, by decreasing the number of photons used to encode each bit, we can efficiently explore the full capacity to carry information of optical fibers, and we can guarantee privacy at the physical layer. We present results for single and entangled photon generation. We encode information in the photons polarization and after transmission we retrieve that information. We discuss the impact of fiber birefringence on the photons polarization.

  18. Thresholdless dressed-atom laser in a photonic band-gap material

    E-print Network

    Gao-xiang Li; Min Luo; Zbigniew Ficek

    2009-06-23

    We demonstrate the capability of complete thresholdless lasing operation between dressed states of a two-level atom located inside a microscopic cavity engineered in a photonic band-gap material. We distinguish between threshold and thresholdless behaves by analyzing the Mandel's Q parameter for the cavity field. We find that the threshold behave depends on whether the spontaneous emission is or is not present on the lasing transition. In the presence of the spontaneous emission, the mean photon number of the cavity field exhibits threshold behavior indicating that the system may operate as an ordinary laser. When the spontaneous emission is eliminated on the lasing transition, no threshold is observed for all values of the pumping rate indicating the system becomes a thresholdless laser. Moreover, we find that under a thresholdless operation, the mean photon number can increase nonlinearly with the pumping rate, and this process is accompanied by a sub-Poisson statistics of the field. This suggests that the nonclassical statistics can be used to distinguish a nonlinear operation of the dressed-atom laser.

  19. Psychological Statistics

    NSDL National Science Digital Library

    Plonsky, Mark

    This site contains materials for a college level undergraduate statistics course. The approach places emphasis on practical application. Examples are shown with hand computations and with the Minitab statistical program (V13.1). There are a couple of spreadsheets as well. Topics include: frequency distributions, graphing techniques, central tendency, variability, relative standing, correlation, dichotomous variables, continuous variables (1 and 2 sample), ANOVA: one way and two way, and nonparametric statistics.

  20. Multi-photon quantum interference in a multi-port integrated photonic device Benjamin J. Metcalf,1,

    E-print Network

    Sheldon, Nathan D.

    circuit complexity. Our experiment paves the way for the next generation of integrated photonic quantum- terference nodes in the circuit and the number of photons distributed among them. There are two key outstanding challenges associated with this task of scaling up integrated photonic circuits to these larger

  1. Superconducting series nanowire detector counting up to twelve photons

    E-print Network

    Zhou, Zili; Mattioli, Francesco; Sahin, Döndü; Frucci, Giulia; Gaggero, Alessandro; Leoni, Roberto; Fiore, Andrea

    2013-01-01

    We demonstrate a superconducting photon-number-resolving detector capable of resolving up to twelve photons at telecommunication wavelengths. It is based on a series array of twelve superconducting NbN nanowire elements, each connected in parallel with an integrated resistor. The photon-induced voltage signals from the twelve elements are summed up into a single readout pulse with a height proportional to the detected photon number. Thirteen distinct output levels corresponding to the detection of n=0-12 photons are observed experimentally. A detailed analysis of the excess noise shows the potential of scaling to an even larger dynamic range.

  2. Superconducting series nanowire detector counting up to twelve photons.

    PubMed

    Zhou, Zili; Jahanmirinejad, Saeedeh; Mattioli, Francesco; Sahin, Döndü; Frucci, Giulia; Gaggero, Alessandro; Leoni, Roberto; Fiore, Andrea

    2014-02-10

    We demonstrate a superconducting photon-number-resolving detector capable of resolving up to twelve photons at telecommunication wavelengths. It is based on a series array of twelve superconducting NbN nanowire elements, each connected in parallel with an integrated resistor. The photon-induced voltage signals from the twelve elements are summed up into a single readout pulse with a height proportional to the detected photon number. Thirteen distinct output levels corresponding to the detection of n = 0-12 photons are observed experimentally. A detailed analysis of the linearity and of the excess noise shows the potential of scaling to an even larger dynamic range. PMID:24663638

  3. Superconducting series nanowire detector counting up to twelve photons

    E-print Network

    Zili Zhou; Saeedeh Jahanmirinejad; Francesco Mattioli; Döndü Sahin; Giulia Frucci; Alessandro Gaggero; Roberto Leoni; Andrea Fiore

    2013-11-25

    We demonstrate a superconducting photon-number-resolving detector capable of resolving up to twelve photons at telecommunication wavelengths. It is based on a series array of twelve superconducting NbN nanowire elements, each connected in parallel with an integrated resistor. The photon-induced voltage signals from the twelve elements are summed up into a single readout pulse with a height proportional to the detected photon number. Thirteen distinct output levels corresponding to the detection of n=0-12 photons are observed experimentally. A detailed analysis of the excess noise shows the potential of scaling to an even larger dynamic range.

  4. Physics at high energy photon photon colliders

    SciTech Connect

    Chanowitz, M.S.

    1994-06-01

    I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.

  5. Descriptive Statistics.

    ERIC Educational Resources Information Center

    Weed, Harrison D., Jr.

    This brief text was written to provide more extensive treatment of descriptive statistics than is ordinarily available in modern statistics textbooks. It is intended for use in conjunction with any college level text. The booklet consists of an introduction, three content oriented chapters, and four appendices devoted to computer programming…

  6. Statistics Manual.

    ERIC Educational Resources Information Center

    Singer, Arlene; And Others

    This guide outlines an Option Y course, which has seven learner objectives geared to providing students with an introduction to the concerns and methods of statistics and equipping pupils to deal with the many statistical matters of importance in society. Topics included in the course are graphs and charts, collection and organization of data,…

  7. Statistical Diversions

    ERIC Educational Resources Information Center

    Petocz, Peter; Sowey, Eric

    2008-01-01

    In this article, the authors focus on hypothesis testing--that peculiarly statistical way of deciding things. Statistical methods for testing hypotheses were developed in the 1920s and 1930s by some of the most famous statisticians, in particular Ronald Fisher, Jerzy Neyman and Egon Pearson, who laid the foundations of almost all modern methods of…

  8. Statistical restoration for robust and secure steganography

    Microsoft Academic Search

    Kaushal Solanki; Kenneth Sullivan; Upamanyu Madhow; B. S. Manjunath; Shivkumar Chandrasekaran

    2005-01-01

    We investigate data hiding techniques that attempt to defeat steganalysis by restoring the statistics of the composite image to resemble that of the cover. The approach is to reserve a number of host symbols for statistical restoration: host statistics perturbed by data embedding are restored by suitably modifying the symbols from the reserved set. While statistical restoration has broad ap-

  9. Photonic lattices for astronomical interferometry

    NASA Astrophysics Data System (ADS)

    Minardi, S.

    2012-05-01

    Regular 2D lattices of evanescently coupled waveguides may provide in the near future photonic components capable of combining interferometrically and simultaneously a large number of telescopes, thus easing the imaging capabilities of optical interferometers. In this paper, the theoretical modelling of the so-called discrete beam combiners (DBCs) is described and compared to the conventional model used for photonic beam combiners for astronomical interferometry. The performance of DBCs as compared to an ideal ABCD beam combiner is discussed and applications to astronomical instrumentation are analysed.

  10. Exploring the limits of multiplexed photon-pair sources for the preparation of pure single-photon states

    E-print Network

    Robert J. A. Francis-Jones; Peter J. Mosley

    2014-09-08

    Current sources of heralded single photons based on nonlinear optics operate in a probabilistic manner. In order to build quantum-enhanced devices based around the use of single photons, compact, turn-key and deterministic sources are required. A possible solution is to multiplex a number of sources to increase the single-photon generation probability and in so doing reducing the waiting time to deliver large numbers of photons simultaneously, from independent sources. Previously it has been shown that, in the ideal case, 17 multiplexed sources allow deterministic generation of heralded single photons [Christ and Silberhorn, Phys. Rev. A 85, 023829 (2012)]. Here we extend this analysis to include undesirable effects of detector inefficiency and photon loss on a number of multiplexed sources using a variety of different detectors for heralding. We compare these systems for fixed signal-to-noise ratio to allow a direct comparison of performance for real- world heralded single photon sources.

  11. First measurement of the quark-to-photon fragmentation function

    Microsoft Academic Search

    Damir Buskulic; David William Casper; I. De Bonis; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; A. Lucotte; M.-N. Minard; P. Odier; B. Pietrzyk; F. Ariztizabal; M. Chmeissani; J. M. Crespo; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; V. Gaitan; Ll. Garrido; M. Martinez; S. Orteu; A. Pacheco; C. Padilla; Fabrizio Palla; A. Pascual; J. A. Perlas; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; A. Farilla; G. Gelao; M. Girone; Giuseppe Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Natali; S. Nuzzo; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; G. Bonvicini; M. Cattaneo; P. Comas; P. Coyle; H. Drevermann; A. Engelhardt; Roger W Forty; M. Frank; R. Hagelberg; J. Harvey; R. Jacobsen; P. Janot; B. Jost; J. Knobloch; Ivan Lehraus; C. Markou; E. B. Martin; P. Mato; H. Meinhard; Adolf G Minten; R. Miquel; T. Oest; P. Palazzi; J. R. Pater; J.-F. Pusztaszeri; F. Ranjard; P E Rensing; Luigi Rolandi; D. Schlatter; M. Schmelling; O. Schneider; W. Tejessy; I. R. Tomalin; A. Venturi; H W Wachsmuth; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack; Ziad J Ajaltouni; Maria Bardadin-Otwinowska; A. Barres; C. Boyer; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J. C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; J.-M. Rossignol; F. Saadi; Tom Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; B. S. Nilsson; A. Kyriakis; Errietta Simopoulou; I. Siotis; Anna Vayaki; K. Zachariadou; A. Blondel; G R Bonneaud; J. C. Brient; P. Bourdon; L. Passalacqua; A. Rougé; M. Rumpf; R. Tanaka; Andrea Valassi; M. Verderi; H L Videau; D. J. Candlin; M. I. Parsons; E. Focardi; G. Parrini; M. Corden; M C Delfino; C H Georgiopoulos; D. E. Jaffe; A. Antonelli; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; V. Chiarella; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; M. Pepe-Altarelli; S. J. Dorris; A. W. Halley; I. ten Have; I. G. Knowles; J. G. Lynch; W. T. Morton; V. O’Shea; C. Raine; P. Reeves; J. M. Scarr; K. Smith; M. G. Smith; A. S. Thompson; F. Thomson; S. Thorn; R. M. Turnbull; U. Becker; O. Braun; C. Geweniger; G. Graefe; P. Hanke; V. Hepp; E. E. Kluge; A. Putzer; B. Rensch; M. Schmidt; J. Sommer; H. Stenzel; K. Tittel; S. Werner; M. Wunsch; R. Beuselinck; David M Binnie; W. Cameron; D. J. Colling; Peter J Dornan; N P Konstantinidis; L. Moneta; A. Moutoussi; J. Nash; G. San Martin; J. K. Sedgbeer; A. M. Stacey; G. Dissertori; P. Girtler; E. Kneringer; D. Kuhn; G. Rudolph; C. K. Bowdery; T. J. Brodbeck; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; Terence Sloan; E. P. Whelan; M. I. Williams; A. Galla; A. M. Greene; K. Kleinknecht; G. Quast; J. Raab; B. Renk; H.-G. Sander; R. Wanke; C. Zeitnitz; Jean-Jacques Aubert; A. M. Bencheikh; C. Bencheikh; C. Benchouk; A. Bonissent; G. Bujosa; D. Calvet; J. Carr; C. Diaconu; F. Etienne; M. Thulasidas; D. Nicod; P. Payre; D. Rousseau; M. Talby; I. Abt; R. Assmann; C. Bauer; W. Blum; D. Brown; H. Dietl; F. Dydak; G. Ganis; C. Gotzhein; K. Jakobs; H. Kroha; G. Lütjens; G. Lutz; W. Männer; H.-G. Moser; R. Richter; A. Rosado-Schlosser; S. Schael; R. Settles; H. Seywerd; U. Stierlin; R. St. Denis; G. Wolf; R. Alemany; J. Boucrot; O. Callot; A. Cordier; F. Courault; M. Davier; L. Duflot; J.-F. Grivaz; Ph Heusse; M. Jacquet; D. W. Kim; F. Le Diberder; J. Lefrançois; A.-M. Lutz; G. Musolino; I. Nikolic; H. J. Park; I. C. Park; M.-H. Schune; S. Simion; J.-J. Veillet; I. Videau; D. Abbaneo; P. Azzurri; G Batignani; G. Batignani; S. Bettarini; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; V. Ciulli; R. Dell’Orso; R. Fantechi; I. Ferrante; L. Foà; F. Forti; A. Giassi; M. A. Giorgi; A. Gregorio; F. Ligabue; A. Lusiani; P. S. Marrocchesi; A. Messineo; G. Rizzo; G. Sanguinetti; A. Sciabà; P. Spagnolo; J. Steinberger; R. Tenchini; G Triggiani; C. Vannini; P. G. Verdini; J. Walsh; A. P. Betteridge; G. A. Blair; L. M. Bryant; F. Cerutti; Y. Gao; M. G. Green; D. L. Johnson; T. Medcalf; L. M. Mir; P. Perrodo; J. A. Strong; V. Bertin; D. R. Botterill; R. W. Clifft; T. R. Edgecock; S. Haywood; M. Edwards; P. Maley; P. R. Norton; J. C. Thompson; B. Bloch-Devaux; P. Colas; H. Duarte; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; B. Marx; P. Perez; J F Renardy; A Roussarie; A. Roussarie; J Schwindling; D. Si Mohand; A. Trabelsi; B. Vallage; R. P. Johnson; H. Y. Kim; A. M. Litke; M. A. McNeil; G. Taylor; A. Beddall; C. N. Booth; R. Boswell; S. Cartwright; F. Combley; I. Dawson; A. Koksal; M. Letho; W. M. Newton; C. Rankin; L. F. Thompson; A. Böhrer; S. Brandt; G. Cowan; E. Feigl; C. Grupen; G. Lutters; J. Minguet-Rodriguez; F. Rivera; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. Della Marina

    1995-01-01

    Earlier measurements at LEP of isolated hard photons in hadronic Z decays, attributed to radiation from primary quark pairs,\\u000a have been extended in the ALEPH experiment to include hard photon productioninside hadron jets. Events are selected where all particles combine democratically to form hadron jets, one of which contains a\\u000a photon with a fractional energyz?0.7. After statistical subtraction of non-prompt

  12. Interfacing GHz-bandwidth heralded single photons with a room-temperature Raman quantum memory

    E-print Network

    P. S. Michelberger; T. F. M. Champion; M. R. Sprague; K. T. Kaczmarek; M. Barbieri; X. M. Jin; D. G. England; W. S. Kolthammer; D. J. Saunders; J. Nunn; I. A. Walmsley

    2014-05-06

    Photonics is a promising platform for quantum technologies. However, photon sources and two-photon gates currently only operate probabilistically. Large-scale photonic processing will therefore be impossible without a multiplexing strategy to actively select successful events. High time-bandwidth-product quantum memories - devices that store and retrieve single photons on-demand - provide an efficient remedy via active synchronisation. Here we interface a GHz-bandwidth heralded single-photon source and a room-temperature Raman memory with a time-bandwidth product exceeding 1000. We store heralded single photons and observe a clear influence of the input photon statistics on the retrieved light, which agrees with our theoretical model. The preservation of the stored field's statistics is limited by four-wave-mixing noise, which we identify as the key remaining challenge in the development of practical memories for scalable photonic information processing.

  13. Juvenile Court Statistics 1985.

    ERIC Educational Resources Information Center

    Snyder, Howard N.; And Others

    This report is the 59th in the "Juvenile Court Statistics" series, a series begun in 1929 which serves as the primary source of information on the activities of juvenile courts. It describes the number and characteristics of delinquency and status offense cases disposed during 1985 by courts with juvenile jurisdiction and addresses some important…

  14. Influence of refractive index matching on the photon diffuse reflectance

    Microsoft Academic Search

    D Y Churmakov; I V Meglinski; D A Greenhalgh

    2002-01-01

    Photon migration in a randomly inhomogeneous, highly scattering and absorbing semi-infinite medium with a plane boundary is considered by a Monte Carlo (MC) technique. The employed MC technique combines the statistical weight scheme and real photon paths simulation, allowing the exclusion of the energy conservation problem. The internal reflection of the scattered radiation on the medium interface is taken into

  15. Geometrically distributed aperiodic circular photonic crystals with broad and isotropic photonic band gaps

    Microsoft Academic Search

    Qing Guo Du; G. Alagappan; H. V. Demir; C. H. Kam; X. W. Sun; P. Wu

    2011-01-01

    In this paper, a new type of circular photonic crystal (CPC) with a geometrical distribution of concentric layers is presented. A broad and isotropic photonic band gap is achieved using this geometrically distributed CPC (GCPC). Also, the influence of the number of concentric layers to the overall band gap of GCPC is studied. It is demonstrated that the band gap

  16. Transitioning from micro to nano-photonics with Photonic Crystal Fibers Maksim Skorobogatiy

    E-print Network

    Skorobogatiy, Maksim

    , functionalization of the PCF microstructure with nano-materials such as quantum dots, carbon nano- tubes or metallicTransitioning from micro to nano-photonics with Photonic Crystal Fibers Maksim Skorobogatiy that contain a large number of micro- and nano-sized voids or layers. It is the complexity of the fiber

  17. Photon-Photon Interactions via Rydberg Blockade

    SciTech Connect

    Gorshkov, Alexey V. [Institute for Quantum Information, California Institute of Technology, Pasadena, California 91125 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States); Otterbach, Johannes [Department of Physics and Research Center OPTIMAS, Technische Universitaet Kaiserslautern, 67663, Kaiserslautern (Germany); Fleischhauer, Michael [Department of Physics and Research Center OPTIMAS, Technische Universitaet Kaiserslautern, 67663, Kaiserslautern (Germany); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States); Pohl, Thomas [Max Planck Institute for the Physics of Complex Systems, 01187 Dresden (Germany); Lukin, Mikhail D. [Physics Department, Harvard University, Cambridge, Massachusetts 02138 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)

    2011-09-23

    We develop the theory of light propagation under the conditions of electromagnetically induced transparency in systems involving strongly interacting Rydberg states. Taking into account the quantum nature and the spatial propagation of light, we analyze interactions involving few-photon pulses. We show that this system can be used for the generation of nonclassical states of light including trains of single photons with an avoided volume between them, for implementing photon-photon gates, as well as for studying many-body phenomena with strongly correlated photons.

  18. Engineering Statistics From "Engineering Statistics" , Top &

    E-print Network

    Kovintavewat, Piya

    Engineering Statistics From "Engineering Statistics" , Top & Wiley, Prapaisri & Pongchanun 2 From "Engineering Statistics" , Top & Wiley, Prapaisri & Pongchanun 3 " "(Sample) (Sampling) ""(Population) " "(Statistics) ""(Parameter) From "Engineering Statistics" , Top & Wiley, Prapaisri

  19. The Single-Photon Router

    E-print Network

    Hoi, Io-Chun; Johansson, Göran; Palomaki, Tauno; Peropadre, Borja; Delsing, Per

    2011-01-01

    We have embedded an artificial atom, a superconducting "transmon" qubit, in an open transmission line and investigated the strong scattering of incident microwave photons ($\\sim6$ GHz). When an input coherent state, with an average photon number $N\\ll1$ is on resonance with the artificial atom, we observe extinction of up to 90% in the forward propagating field. We use two-tone spectroscopy to study scattering from excited states and we observe electromagnetically induced transparency (EIT). We then use EIT to make a single-photon router, where we can control to what output port an incoming signal is delivered. The maximum on-off ratio is around 90% with a rise and fall time on the order of nanoseconds, consistent with theoretical expectations. The router can easily be extended to have multiple output ports and it can be viewed as a rudimentary quantum node, an important step towards building quantum information networks.

  20. The Single-Photon Router

    E-print Network

    Io-Chun Hoi; C. M. Wilson; Göran Johansson; Tauno Palomaki; Borja Peropadre; Per Delsing

    2011-03-09

    We have embedded an artificial atom, a superconducting "transmon" qubit, in an open transmission line and investigated the strong scattering of incident microwave photons ($\\sim6$ GHz). When an input coherent state, with an average photon number $N\\ll1$ is on resonance with the artificial atom, we observe extinction of up to 90% in the forward propagating field. We use two-tone spectroscopy to study scattering from excited states and we observe electromagnetically induced transparency (EIT). We then use EIT to make a single-photon router, where we can control to what output port an incoming signal is delivered. The maximum on-off ratio is around 90% with a rise and fall time on the order of nanoseconds, consistent with theoretical expectations. The router can easily be extended to have multiple output ports and it can be viewed as a rudimentary quantum node, an important step towards building quantum information networks.

  1. Rainbow statistics

    E-print Network

    Michele Arzano; Dario Benedetti

    2008-09-04

    Non-commutative quantum field theories and their global quantum group symmetries provide an intriguing attempt to go beyond the realm of standard local quantum field theory. A common feature of these models is that the quantum group symmetry of their Hilbert spaces induces additional structure in the multiparticle states which reflects a non-trivial momentum-dependent statistics. We investigate the properties of this "rainbow statistics" in the particular context of $\\kappa$-quantum fields and discuss the analogies/differences with models with twisted statistics.

  2. Statistics Clinic

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.; Foy, Millennia; Ploutz-Snyder, Robert; Fiedler, James

    2014-01-01

    Do you have elevated p-values? Is the data analysis process getting you down? Do you experience anxiety when you need to respond to criticism of statistical methods in your manuscript? You may be suffering from Insufficient Statistical Support Syndrome (ISSS). For symptomatic relief of ISSS, come for a free consultation with JSC biostatisticians at our help desk during the poster sessions at the HRP Investigators Workshop. Get answers to common questions about sample size, missing data, multiple testing, when to trust the results of your analyses and more. Side effects may include sudden loss of statistics anxiety, improved interpretation of your data, and increased confidence in your results.

  3. photonics.com

    NSDL National Science Digital Library

    Laurin Publishing

    It's everything photonics! From the the publishers of Photonics Spectra magazine this website will help you gain technical and practical information for every aspect of the global industry, integrating all segments of photonics: optics, lasers, imaging, fiber optics, electro-optics as well as photonic component manufacturing.

  4. Photonic crystal circuits

    Microsoft Academic Search

    A. R. McGurn

    2001-01-01

    A theory is presented for the flow of electromagnetic energy in photonic crystal circuits. Photonic crystal circuits are waveguide networks in photonic crystals. The theory is based on a set of difference equations which describe the propagation of electromagnetic waves in particular types of photonic crystal waveguides. Solutions are given for the transmission and reflection of electromagnetic waves from barriers

  5. Opportunities for single-photon detection using visible light photon counters

    NASA Astrophysics Data System (ADS)

    Kim, Jungsang; McKay, Kyle S.; Stapelbroek, Maryn G.; Hogue, Henry H.

    2011-05-01

    Visible light photon counters (VLPCs) are solid-state devices providing high quantum efficiency (QE) photon detection (>88%) with photon number resolving capability and low timing jitter (~250 ps). VLPC features high QE in the 0.4-1.0?m wavelength range, as the main photon absorption mechanism is provided by electron-hole pair generation across the silicon bandgap. In this paper, we will discuss the optical and electrical operating principles of VLPCs, and propose a range of device optimization paths that improves various aspects of VLPC for advanced quantum optics and quantum information processing experiments, both in the UV and the telecom wavelength range.

  6. Broad flattop transparent photonic band in truncated photonic crystals composed of the symmetric unit cell

    NASA Astrophysics Data System (ADS)

    Du, Guiqiang; Li, Lixin; Jiang, Haitao; Li, Yunhui; Zhang, Liwei; Zhao, Junfang; Yang, Tianlin; Wu, Zhongchen; Song, Shumei; Li, Yanhui; Lv, Maoshui

    2010-10-01

    We theoretically show that a one-dimensional finite all-dielectric periodic structure composed of symmetric unit cells can possess a broad flattop transparent photonic band. In contrast to the conventional viewpoint that the thickness of the truncated photonic crystals affects the transmission within the pass band, the transparent photonic band is insensitive to the change of the periodic number since the equivalent refractive indices of our structures can be nearly equal to that of the background in a wide frequency range. With easy fabrication, this broad flattop transparent photonic band will play an important role in the broadband filtering.

  7. Broad flattop transparent photonic band in truncated photonic crystals composed of the symmetric unit cell

    NASA Astrophysics Data System (ADS)

    Du, Guiqiang; Li, Lixin; Jiang, Haitao; Li, Yunhui; Zhang, Liwei; Zhao, Junfang; Yang, Tianlin; Wu, Zhongchen; Song, Shumei; Li, Yanhui; Lv, Maoshui

    2011-02-01

    We theoretically show that a one-dimensional finite all-dielectric periodic structure composed of symmetric unit cells can possess a broad flattop transparent photonic band. In contrast to the conventional viewpoint that the thickness of the truncated photonic crystals affects the transmission within the pass band, the transparent photonic band is insensitive to the change of the periodic number since the equivalent refractive indices of our structures can be nearly equal to that of the background in a wide frequency range. With easy fabrication, this broad flattop transparent photonic band will play an important role in the broadband filtering.

  8. Library Research and Statistics. Research on Libraries and Librarianship in 2002; Number of Libraries in the United States and Canada; Highlights of NCES Surveys; Library Acquisition Expenditures, 2001-2002: U.S. Public, Academic, Special, and Government Libraries; LJ Budget Report: A Precarious Holding Pattern; Price Indexes for Public and Academic Libraries; Library Buildings 2002: The Building Buck Doesn't Stop Here.

    ERIC Educational Resources Information Center

    Lynch, Mary Jo; Oder, Norman; Halstead, Kent; Fox, Bette-Lee

    2003-01-01

    Includes seven reports that discuss research on libraries and librarianship, including academic, public, and school libraries; awards and grants; number of libraries in the United States and Canada; National Center for Education Statistics results; library expenditures for public, academic, special, and government libraries; library budgets; price…

  9. The photon wave function

    NASA Astrophysics Data System (ADS)

    Muthukrishnan, A.; Scully, M. O.; Zubairy, M. S.

    2005-08-01

    We review and sharpen the concept of a photon wave function based on the quantum theory of light. We argue that a point-like atom serves as the archetype for both the creation and detection of photons. Spontaneous emission from atoms provides a spatially localized source of photon states that serves as a natural wave packet basis for quantum states of light. Photodetection theory allows us to give operational meaning to the photon wave function which, for single photons, is analogous to the electric field in classical wave optics. Entanglement between photons, and the uniquely quantum phenomena that result from it, are exemplified by two-photon wave functions.

  10. Notoph-Graviton-Photon Coupling

    E-print Network

    Valeriy V. Dvoeglazov

    2014-11-16

    In the sixties Ogievetskii and Polubarinov proposed the concept of a notoph, whose helicity properties are complementary to those of a photon. Later, Kalb and Ramond (and others) developed this theoretical concept. And, at the present times it is widely accepted. We analyze the quantum theory of antisymmetric tensor fields with taking into account mass dimensions of notoph and photon. It appears to be possible to describe both photon and notoph degrees of freedom on the basis of the modified Bargmann-Wigner formalism for the symmetric second-rank spinor. Next, we proceed to derive equations for the symmetric tensor of the second rank on the basis of the Bargmann-Wigner formalism in a straightforward way. The symmetric multispinor of the fourth rank is used. It is constructed out of the Dirac 4-spinors. Due to serious problems with the interpretation of the results obtained on using the standard procedure we generalize it and obtain the spin-2 relativistic equations, which are consistent with the general relativity. The importance of the 4-vector field (and its gauge part) is pointed out. Thus, we present the full theory which contains photon, notoph (the Kalb-Ramond field) and the graviton. The relations of this theory with the higher spin theories are established. In fact, we deduced the gravitational field equations from relativistic quantum mechanics. We estimate possible interactions, fermion-notoph, graviton-notoph, photon-notoph. PACS number: 03.65.Pm, 04.50.-h, 11.30.Cp

  11. Mathematical Statistics

    NSDL National Science Digital Library

    Dudley, Richard

    Created by Richard Dudley of the Massachusetts Institute of Technology, this lesson, Mathematical Statistics, is a graduate-level course featuring book chapters and sections presented as lecture notes, problem sets, exams, and a description for an optional term-paper. The course covers: decision theory, estimation, confidence intervals, hypothesis testing, asymptotic efficiency of estimates, exponential families, sequential analysis, and large sample theory. This is a comprehensive overview of this upper level statistics course.

  12. Statistical Mechanics

    Microsoft Academic Search

    V. Jaksi ´; C.-A. Pillet

    1937-01-01

    We review and further develop a mathematical framework for non-equilibrium quantum statistical mechanics recently proposed in (JP4, JP5, JP6, Ru3, Ru4, Ru5, Ru6). In the alge- braic formalism of quantum statistical mechanics we introduce notions of non-equilibrium steady states, entropy production and heat fluxes, and study their properties. Our basic paradigm is a model of a small (finite) quantum system

  13. Photon log

    SciTech Connect

    Chudy, S.

    1981-01-01

    Gravel packing has been used in the Schoonebeek oil field of The Netherlands in recent years to allow sand- free production. With increased thermal activity in the field, i.e., steam injection, the success of gravel packing operations becomes more important. Well completion problems are exaggerated by high temperature and deviation. The field operator aims to gravel pack up to a minimum of 10 m inside the casing shoe with the top of the slotted liner or wire wrap screen also inside the casing. The Photon Log now is being used to indicate the quality of the gravel packing operation, particularly the gravel top, thus aiding decision-making on whether or not corrective action is needed. The objective is to obtain all the information from one logging trip into the hole after the gravel pack operation, without needing a base log run beforehand. This work discusses the theory of operation and calibration technique, results of logs with field examples, and plans for the future.

  14. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Lofquist, William S.

    1998-01-01

    Provides data on prices of U.S. and foreign materials; book title output and average prices, 1996 final and 1997 preliminary figures; book sales statistics, 1997--AAP preliminary estimates; U.S. trade in books, 1997; international book title output, 1990-95; book review media statistics; and number of book outlets in the U.S. and Canada. (PEN)

  15. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Greco, Albert N.

    1999-01-01

    Presents: "Prices of United States and Foreign Published Materials"; "Book Title Output and Average Prices"; "Book Sales Statistics, 1998"; "United States Book Exports and Imports: 1998"; "International Book Title Output: 1990-96"; "Number of Book Outlets in the United States and Canada"; and "Book Review Media Statistics". (AEF)

  16. Processing time-correlated single photon counting data to acquire range images

    E-print Network

    Buller, Gerald S.

    photon counting (TCSPC) is a statistical sampling technique with single photon detec- tion sensitivity of each optical pulse is split off and sent to a trigger avalanche photodiode (APD), which acts from either the target or reference are detected by an actively quenched single photon avalanche diode

  17. Graded photonic quasicrystals.

    PubMed

    Dyachenko, Pavel N; Pavelyev, Vladimir S; Soifer, Victor A

    2012-06-15

    We introduce graded photonic quasicrystals and investigate properties of such structures on the example of a Luneburg lens based on a dodecagonal photonic quasicrystal. It is shown that the graded photonic quasicrystal lens has better focusing properties as compared with the graded photonic crystal lens in a frequency range suitable for experimental realization. The proposed graded photonic quasicrystals can be used in optical systems where compact and powerful focusing elements are required. PMID:22739847

  18. Modern Statistical Methods for GLAST Event Analysis

    SciTech Connect

    Morris, Robin D.; /RIACS, Mtn. View; Cohen-Tanugi, Johann; /SLAC /KIPAC, Menlo Park

    2007-04-10

    We describe a statistical reconstruction methodology for the GLAST LAT. The methodology incorporates in detail the statistics of the interactions of photons and charged particles with the tungsten layers in the LAT, and uses the scattering distributions to compute the full probability distribution over the energy and direction of the incident photons. It uses model selection methods to estimate the probabilities of the possible geometrical configurations of the particles produced in the detector, and numerical marginalization over the energy loss and scattering angles at each layer. Preliminary results show that it can improve on the tracker-only energy estimates for muons and electrons incident on the LAT.

  19. Modern Statistical Methods for GLAST Event Analysis

    E-print Network

    Robin D. Morris; Johann Cohen-Tanugi

    2007-03-28

    We describe a statistical reconstruction methodology for the GLAST LAT. The methodology incorporates in detail the statistics of the interactions of photons and charged particles with the tungsten layers in the LAT, and uses the scattering distributions to compute the full probability distribution over the energy and direction of the incident photons. It uses model selection methods to estimate the probabilities of the possible geometrical configurations of the particles produced in the detector, and numerical marginalization over the energy loss and scattering angles at each layer. Preliminary results show that it can improve on the tracker-only energy estimates for muons and electrons incident on the LAT.

  20. Statistical Constraints on Joy's Law

    NASA Astrophysics Data System (ADS)

    Amouzou, Ernest C.; Munoz-Jaramillo, Andres; Martens, Petrus C.; DeLuca, Edward E.

    2014-06-01

    Using sunspot data from the observatories at Mt. Wilson and Kodaikanal, active region tilt angles are analyzed for different active region sizes and latitude bins. A number of similarly-shaped statistical distributions were fitted to the data using maximum likelihood estimation. In all cases, we find that the statistical distribution best describing the number of active regions at a given tilt angle is a Laplace distribution with the form (2?)-1*exp(-|x-?|/?), with 2° ? ? ? 11°, and 10° ? ? ? 40°.

  1. STATISTICAL LITERACY: THINKING CRITICALLY ABOUT STATISTICS

    Microsoft Academic Search

    Milo Schield

    Statistical literacy is the ability to read and interpret data: the ability to use statistics as evidence in arg u- ments. Statistical literacy is a competency: the ability to think critically about statistics. This introduction defines statistical literacy as a science of method, com- pares statistical literacy with traditional statistics and reviews some of the elements in reading and interpret-

  2. Photonic crystals for improved light harvesting

    NASA Astrophysics Data System (ADS)

    Clays, Koen; Kolaric, Branko; Baert, Kasper; Vallée, Renaud A. L.

    2008-08-01

    The fluorescence of chromophores embedded in a photonic crystal is inhibited by the presence of a photonic pseudo-gap. We present the influence of such an incomplete bandgap on the emission and energy transfer by studying the steady-state and time-resolved emission properties of both a donor and an acceptor fluorophore in a self-assembled photonic crystal. Our results clearly show an inhibition of the donor emission and a concomitant enhancement of the acceptor emission, indicating improved energy transfer from donor to acceptor. This is explained by the decreased number of available photonic modes for radiative decay for the donor in a suitable engineered photonic crystal with respect to in the effective homogeneous medium.

  3. Teleporting photonic qudits using multimode quantum scissors.

    PubMed

    Goyal, Sandeep K; Konrad, Thomas

    2013-01-01

    Teleportation plays an important role in the communication of quantum information between the nodes of a quantum network and is viewed as an essential ingredient for long-distance Quantum Cryptography. We describe a method to teleport the quantum information carried by a photon in a superposition of a number d of light modes (a "qudit") by the help of d additional photons based on transcription. A qudit encoded into a single excitation of d light modes (in our case Laguerre-Gauss modes which carry orbital angular momentum) is transcribed to d single-rail photonic qubits, which are spatially separated. Each single-rail qubit consists of a superposition of vacuum and a single photon in each one of the modes. After successful teleportation of each of the d single-rail qubits by means of "quantum scissors" they are converted back into a qudit carried by a single photon which completes the teleportation scheme. PMID:24352610

  4. Number Line

    NSDL National Science Digital Library

    Clarity Innovations, Inc.

    2013-11-22

    This iOS app helps students to visualize number sentences and create models for addition, subtractions, multiplication, and division. The number line can be adjusted to represent multiples of numbers from one to one hundred.

  5. UCGE Reports Number 20042

    E-print Network

    Calgary, University of

    -time statistical testing and implementation procedure for use in kinematic GPS positioning is given basedUCGE Reports Number 20042 Quality Control for Differential Kinematic GPS Positioning (URL: http OF CALGARY QUALITY CONTROL FOR DIFFERENTIAL KINEMATIC GPS POSITIONING BY GANG LU A THESIS SUBMITTED

  6. Mystery Number

    NSDL National Science Digital Library

    TERC

    2010-01-01

    Combine logic and numbers in this game for all ages. Players start with a 10x10 grid of the numbers 1 to 100. One person chooses a secret number and announces the range in which it falls. Other players ask yes or no questions to identify the number. They cross out the numbers on the board that are no longer possibilities. The player who identifies the secret number wins. Available as a downloadable pdf and in Spanish.

  7. A physicist's approach to number partitioning

    Microsoft Academic Search

    Stephan Mertens

    2001-01-01

    The statistical physics approach to the number partioning problem, a classical NP- hard problem, is both simple and rewarding. Very basic notions and methods from statistical mechanics are enough to obtain analytical results for the phase boundary that separates the \\

  8. Topological Invariants in Point Group Symmetric Photonic Topological Insulators

    E-print Network

    Chen, Xiao-Dong; Chen, Wen-Jie; Wang, Jia-Rong; Dong, Jian-Wen

    2014-01-01

    We proposed a group-theory method to calculate topological invariant in bi-isotropic photonic crystals invariant under crystallographic point group symmetries. Spin Chern number has been evaluated by the eigenvalues of rotation operators at high symmetry k-points after the pseudo-spin polarized fields are retrieved. Topological characters of photonic edge states and photonic band gaps can be well predicted by total spin Chern number. Nontrivial phase transition is found in large magnetoelectric coupling due to the jump of total spin Chern number. Light transport is also issued at the {\\epsilon}/{\\mu} mismatching boundary between air and the bi-isotropic photonic crystal. This finding presents the relationship between group symmetry and photonic topological systems, which enables the design of photonic nontrivial states in a rational manner.

  9. Collective two-particle resonances induced by photon entanglement

    NASA Astrophysics Data System (ADS)

    Richter, Marten; Mukamel, Shaul

    2011-06-01

    An assembly of noninteracting atoms may become correlated upon interaction with entangled photons, and certain elements of their joint density matrix can then show collective resonances. We explore experimental signatures of these resonances in the nonlinear response of a pair of two-level atoms. We find that these resonances are canceled out in stimulated signals such as pump-probe and two-photon absorption due to the destructive interference of two-photon-absorption and emission pathways in the joint two-particle space. However, they may be observed in photon statistics (Hanbury-Brown-Twiss) measurements through the attenuation of two-time intensity correlations.

  10. Curvature independence of statistical entropy

    E-print Network

    Judy Kupferman

    2014-07-20

    We examine the statistical number of states, from which statistical entropy can be derived, and we show that it is an explicit function of the metric and thus observer dependent. We find a constraint on a transformation of the metric that preserves the number of states but does not preserve curvature. In showing exactly how curvature independence arises in the conventional definition of statistical entropy, we gain a precise understanding of the direction in which it needs to be redefined in the treatment of black hole entropy.

  11. Bayesian reconstruction of photon interaction sequences for high-resolution PET detectors

    PubMed Central

    Pratx, Guillem

    2013-01-01

    Realizing the full potential of high-resolution positron emission tomography (PET) systems involves accurately positioning events in which the annihilation photon deposits all its energy across multiple detector elements. Reconstructing the complete sequence of interactions of each photon provides a reliable way to select the earliest interaction because it ensures that all the interactions are consistent with one another. Bayesian estimation forms a natural framework to maximize the consistency of the sequence with the measurements while taking into account the physics of ?-ray transport. An inherently statistical method, it accounts for the uncertainty in the measured energy and position of each interaction. An algorithm based on maximum a posteriori (MAP) was evaluated for computer simulations. For a high-resolution PET system based on cadmium zinc telluride detectors, 93.8% of the recorded coincidences involved at least one photon multiple-interactions event (PMIE). The MAP estimate of the first interaction was accurate for 85.2% of the single photons. This represents a two-fold reduction in the number of mispositioned events compared to minimum pair distance, a simpler yet efficient positioning method. The point-spread function of the system presented lower tails and higher peak value when MAP was used. This translated into improved image quality, which we quantified by studying contrast and spatial resolution gains. PMID:19652293

  12. Heavy flavor production from photons and hadrons

    SciTech Connect

    Heusch, C.A.

    1982-01-01

    The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e/sup +/e/sup -/ annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy flavors from spacelike photons, heavy flavors from real photons, and heavy flavors from hadron-hadron collisions are discussed. (WHK)

  13. Number Factory

    NSDL National Science Digital Library

    Michiel Doorman

    2003-01-01

    This interactive game develops fluency and flexibility with whole number operations. In each round the player is given 4 single-digit whole numbers, presented in the context of a factory. The player uses each number exactly once with the interactive calculator to arrive as close as possible to a given target number.

  14. Physical meaning of the photon wave function

    NASA Astrophysics Data System (ADS)

    Inagaki, Toshio

    1998-03-01

    Recently, the author [Phys. Rev. A 49, 2839 (1994)] proposed a quantum-mechanical theory of a photon, in which negative energy states can be dismissed from physical photon states without causing any difficulties. In this Brief Report the physical meaning of a photon wave function is investigated more precisely. The interpretation of a photon wave function as a probability amplitude is guaranteed by requiring the coarse-grained condition that the linear dimensions of a volume or a surface concerned in the configuration space are large compared to the photon wavelengths. The calculation made here is essentially based on that presented by Mandel [Phys. Rev. 144, 1071 (1966)] in his analysis of the photon number operator. But our calculation includes that of Mandel as the zeroth-order approximation. As a result, it is shown that although the position operator x⁁ in the ordinary quantum mechanics be considered a correct photon operator strictly cannot, it becomes meaningful to some extent under the coarse-grained condition. In connection with x⁁, we also examine the velocity operator [x⁁,H⁁]/i? (H⁁ is the photon Hamiltonian), and show that the probability current density is definable under the coarse-grained condition.

  15. Multiplexing photons with a binary division strategy

    NASA Astrophysics Data System (ADS)

    Schmiegelow, Christian Tomás; Larotonda, Miguel Antonio

    2014-08-01

    We present a scheme to produce clock-synchronized photons from a single parametric downconversion source with a binary division strategy. The time difference between a clock and detections of the herald photons determines the amount of delay that must be imposed to a photon by actively switching different temporal segments, so that all photons emerge from the output with their wavepackets temporally synchronized with the temporal reference. The operation is performed using a binary division configuration which minimizes the passages through switches. Finally, we extend this scheme to the production of many synchronized photons and find expressions for the optimal amount of correction stages as a function of the pair generation rate and the target coherence time. Our results show that, for the generation of this heralded single-photon per output state at an optimized input photon flux, the output rate of our scheme scales essentially with the reciprocal of the target output photon number. With current technology, rates of up to 104 synchronized pairs per second could be observed with only 7 correction stages.

  16. Photonics: how to get familiar with it

    NASA Astrophysics Data System (ADS)

    Senderáková, Dagmar; Mesaros, Vladimir; Strba, Anton

    2010-12-01

    Year 2010 brought the 50th anniversary of laser. Our century seems to be called the photon-century. Light in our lives plays both pervasive and primordial role. To describe the new role of today "interdisciplinary optics" a new term - photonics appeared. The term was coined in 1967 by Pierre Aigrain, a French scientist, who defined photonics as the science of the harnessing of light. Photonics encompasses the generation of light, the detection of light, the management of light through guidance, manipulation, and amplification, and most importantly, its utilisation for the benefit of mankind. Number of photonics applications proves its importance. On one side, there is a demand for skilled people with photonics training. On the other side, nearly everyone is affected by science in a way and it would be useful to have at least a basic understanding of scientific principles. However, it is not a brand-new idea, an effort to popularise new scientific achievements has still been present. The contribution is based on experience of popularising photonics to high school students and attracting undergraduate University students for basis of optics via photonics. The aim of it is to share and exchange experience.

  17. New photon-added and photon-depleted coherent states associated with inverse q-boson operators: nonclassical properties

    NASA Astrophysics Data System (ADS)

    Naderi, M. H.; Soltanolkotabi, M.; Roknizadeh, R.

    2004-03-01

    In this paper, we introduce a new family of photon-added as well as photon-depleted q-deformed coherent states related to the inverse q-boson operators. These states are constructed via the generalized inverse q-boson operator actions on a newly introduced family of q-deformed coherent states (Quesne C 2002 J. Phys. A: Math. Gen. 35 9213) which are defined by slightly modifying the maths-type q-deformed coherent states. The quantum statistical properties of these photon-added and photon-depleted states, such as quadrature squeezing and photon-counting statistics, are discussed analytically and numerically in the context of both conventional (nondeformed) and deformed quantum optics.

  18. Number Flash

    NSDL National Science Digital Library

    Mitchell Mark

    2013-03-10

    This iOS app helps students make the transition from counting to number recognition by thinking of a number of objects in relation to five and ten. The app displays a set number of items from one to twenty in ten frames then flashes away after the preset number of seconds. The user must identify the number that was shown on the ten frames.

  19. Juvenile Court Statistics 1967. Children's Bureau Statistical Series 93.

    ERIC Educational Resources Information Center

    Children's Bureau (DHEW), Washington, DC.

    A summary of delinquency, traffic, and other cases, sources and limitations of data, and the definition of six terms precedes 14 tables of statistics. Tables cover the following cases disposed of in 1967: number of delinquency cases; manner of handling cases; rate of delinquency cases; percent change in delinquency cases; number and manner of…

  20. Statistical Engineering

    NSDL National Science Digital Library

    Annis, Charles

    A good resource for problems in statistics in engineering. Contains some applets, and good textual examples related to engineering. Some topics include Monte Carlo method, Central Limit Theorem, Risk, Logistic Regression, Generalized Linear Models, and Confidence. Overall, this is a well presented and good site for anyone interested in engineering or mathematics.

  1. Statistical Information

    E-print Network

    Mitchell, Tom

    , or a set of cdf's for a statistical problem based on data. Inference: Making predictions, computing of x that can be used for reasoning, decision making, predicting, communicating, etc. Task is often #12; Inference vs. Learning Estimation/Learning: Selecting parameters, a distribution over parameters

  2. Statistical Java

    NSDL National Science Digital Library

    Anderson-Cook, C.

    This is a collection of applets regarding various topics in statistics. Topics include central limit theorem, probability distributions, hypothesis testing, power, confidence intervals, correlation, control charts, experimental design, data analysis, and regression. Each topic has a description page and links to one or more applets.

  3. Scalable Spatial Superresolution Using Entangled Photons

    NASA Astrophysics Data System (ADS)

    Rozema, Lee A.; Bateman, James D.; Mahler, Dylan H.; Okamoto, Ryo; Feizpour, Amir; Hayat, Alex; Steinberg, Aephraim M.

    2014-06-01

    N00N states—maximally path-entangled states of N photons—exhibit spatial interference patterns sharper than any classical interference pattern. This is known as superresolution. However, even given perfectly efficient number-resolving detectors, the detection efficiency of all previous measurements of such interference would decrease exponentially with the number of photons in the N00N state, often leading to the conclusion that N00N states are unsuitable for spatial measurements. A technique known as the "optical centroid measurement" has been proposed to solve this and has been experimentally verified for photon pairs; here we present the first extension beyond two photons, measuring the superresolution fringes of two-, three-, and four-photon N00N states. Moreover, we compare the N00N-state interference to the corresponding classical superresolution interference. Although both provide the same increase in spatial frequency, the visibility of the classical fringes decreases exponentially with the number of detected photons. Our work represents an essential step forward for quantum-enhanced measurements, overcoming what was believed to be a fundamental challenge to quantum metrology.

  4. Occupational Employment Statistics

    NSDL National Science Digital Library

    US occupations are featured in this information-rich resources from the Bureau of Labor Statistics. The 1996 Occupational Employment Statistics Survey differs from previous surveys in that it includes wage data by occupation for the first time. The site contains a description of the survey and complete national and state data for 760 occupations in seven major areas. Included are occupation title, number of employees, hourly mean and median wage, and an OES code number that provides information about the occupation and its employment distribution by wage range where surveyed (distribution is for the national survey only). An occupational search engine is forthcoming. The site also contains information about previous OES surveys back to 1988.

  5. Four Faculty Positions Applied Statistics & Computational Statistics

    E-print Network

    Shepp, Larry

    Four Faculty Positions Applied Statistics & Computational Statistics The Department of Statistics at the Assistant Professor rank. Two positions are open in the area of Applied Statistics, with a focus on the development of statistical methodology and statistical consulting. The other two positions are open

  6. A square root analog to digital converter to optimally convert photonic signals for computed tomography

    E-print Network

    Bieniosek, Matthew (Matthew F.)

    2010-01-01

    The arrival of photons at a given location is a Poisson process with an associated shot noise which rises with the square root of the number of photons received. An analog-to-digital converter (ADC) with a square root ...

  7. Thermodynamics of cellular statistical inference

    NASA Astrophysics Data System (ADS)

    Lang, Alex; Fisher, Charles; Mehta, Pankaj

    2014-03-01

    Successful organisms must be capable of accurately sensing the surrounding environment in order to locate nutrients and evade toxins or predators. However, single cell organisms face a multitude of limitations on their accuracy of sensing. Berg and Purcell first examined the canonical example of statistical limitations to cellular learning of a diffusing chemical and established a fundamental limit to statistical accuracy. Recent work has shown that the Berg and Purcell learning limit can be exceeded using Maximum Likelihood Estimation. Here, we recast the cellular sensing problem as a statistical inference problem and discuss the relationship between the efficiency of an estimator and its thermodynamic properties. We explicitly model a single non-equilibrium receptor and examine the constraints on statistical inference imposed by noisy biochemical networks. Our work shows that cells must balance sample number, specificity, and energy consumption when performing statistical inference. These tradeoffs place significant constraints on the practical implementation of statistical estimators in a cell.

  8. Isoscaling in statistical models

    Microsoft Academic Search

    M. B. Tsang; C. K. Gelbke; X. D. Liu; W. G. Lynch; W. P. Tan; G. Verde; H. S. Xu; W. A. Friedman; R. Donangelo; S. R. Souza; C. B. Das; S. Das Gupta; D. Zhabinsky

    2001-01-01

    Different statistical multifragmentation models have been used to study isoscaling, i.e., the factorization of the isotope ratios from two reactions, into fugacity terms of proton and neutron number, R21(N,Z)=Y2(N,Z)\\/Y1(N,Z)=C exp(alphaN+betaZ). Even though the primary isotope distributions are quite different from the final distributions due to evaporation from the excited fragments, the values of alpha and beta are not much affected

  9. Optical nonlinearities near single photon level with a quantum dot coupled to a photonic crystal cavity

    NASA Astrophysics Data System (ADS)

    Sridharan, Deepak

    Over the last decade, exponential increase of information bandwidth over the internet and other communication media has increased the total power consumed by the devices associated with information exchange. With ever increasing number of users, and packing of a higher number of devices onto a chip, there is a great need for reduction in not only the power consumption of the devices but also the costs associated with information transfer. Currently, the benchmark in the energy consumption per logic operation is at femtojoule level and is set by the CMOS industry. However, optical devices based on single photon emitters coupled to a microcavity have the potential to reduce the optical power dissipation down to attojoule levels wherein only few 10s of photons are consumed for a logic operation. This work presents our theoretical and experimental efforts towards realization of all optical device based on the enhanced nonlinearities of a single photon emitter in a photonic crystal cavity. We show that a single quantum dot coupled to a photonic crystal cavity can be used to route an incoming optical beam with optical power dissipation of 14 attojoules, corresponding to only 65 photons. This value is well below the operational level for current CMOS devices indicating the potential for chip based optical transistors for reduction in energy consumption. The single photon emitters that we use to create the nonlinearity are the quantum dots, which are semiconductor nanostructures that exhibit a discrete energy spectrum. The interaction of the quantum dot, with light confined inside a photonic crystal cavity, results in strong atom-photon interactions which can be used for ultra-low power all optical switching. The strong interactions between a quantum dot and photonic crystal cavity can be further utilized to realize quantum computation schemes on a chip. I also describe techniques for integrating this transistor into an optical circuit, and discuss methods for post fabrication tuning to make reconfigurable active photonic devices that implement optical data processing at low light levels.

  10. Nifty Numbers!

    NSDL National Science Digital Library

    Miss.Cochran

    2008-03-26

    You will be working with numbers in all sorts of ways. First, you will play cop by picking numbers based on their divisibility. Then you will be adding and subtracting fractions in two fun and exciting games. First, as a cop, you will catch numbers that are divisible by which ever number you pick, avoinding crashing into non-divisible numbers. Number Cop-Divisibility Now, play Fishy Fractions! and help feed the seagull by practicing adding fractions. Make sure you read the instructions before getting started! Make sure to simplify your answers! After you ...

  11. Efficiency vs. multi-photon contribution test for quantum dots

    E-print Network

    Ana Predojevic; Miroslav Jezek; Tobias Huber; Harishankar Jayakumar; Thomas Kauten; Glenn S. Solomon; Radim Filip; Gregor Weihs

    2014-03-19

    The development of linear quantum computing within integrated circuits demands high quality semiconductor single photon sources. In particular, for a reliable single photon source it is not sufficient to have a low multi-photon component, but also to possess high efficiency. We investigate the photon statistics of the emission from a single quantum dot with a method that is able to sensitively detect the trade-off between the efficiency and the multi-photon contribution. Our measurements show, that the light emitted from the quantum dot when it is resonantly excited possess a very low multi-photon content. Additionally, we demonstrated, for the first time, the non-Gaussian nature of the quantum state emitted from a single quantum dot.

  12. Composite Photon Theory Versus Elementary Photon Theory

    E-print Network

    Walton A. Perkins

    2015-03-02

    The purpose of this paper is to show that the composite photon theory measures up well against the Standard Model's elementary photon theory. This is done by comparing the two theories area by area. Although the predictions of quantum electrodynamics are in excellent agreement with experiment (as in the anomalous magnetic moment of the electron), there are some problems, such as the difficulty in describing the electromagnetic field with the four-component vector potential because the photon has only two polarization states. In most areas the two theories give similar results, so it is impossible to rule out the composite photon theory. Pryce's arguments in 1938 against a composite photon theory are shown to be invalid or irrelevant. Recently, it has been realized that in the composite theory the antiphoton does not interact with matter because it is formed of a neutrino and an antineutrino with the wrong helicity. This leads to experimental tests that can determine which theory is correct.

  13. Plasma photonic crystal

    Microsoft Academic Search

    Wei Li; Yong Zhao; Ruizhen Cui; Haitao Zhang

    2009-01-01

    Plasma photonic crystals are presented in this paper. A plasma photonic crystal can control the propagation of electromagnetic\\u000a waves. Similar to other photonic crystals, the permittivity of a plasma photonic crystal is distributed as periodic arrays.\\u000a The properties of periodic arrays of plasma can broaden the range of frequency and enhance the efficiency of beam-wave interaction.\\u000a In special uses, the

  14. Thermonuclear reaction rates from statistical model calculations

    Microsoft Academic Search

    Friedrich-Karl Thielemann; James W. Truran; Marcel Arnould

    1986-01-01

    The quality of statistical model predictions for thermonuclear reaction rates is based on the accuracy of theoretical determinations of particle and photon transmission coefficients as well as that of the level densities of excited states in nuclei. The square well potentials for neutrons, protons, and alpha particles, used in previous approaches, have been replaced in this work by realistic optical

  15. Problems on Non-Equilibrium Statistical Physics 

    E-print Network

    Kim, Moochan

    2011-08-08

    Four problems in non-equilibrium statistical physics are investigated: 1. The thermodynamics of single-photon gas; 2. Energy of the ground state in Multi-electron atoms; 3. Energy state of the H2 molecule; and 4. The Condensation behavior in N...

  16. Denoising by Higher Order Statistics Tanja Teubera

    E-print Network

    Steidl, Gabriele

    data. In literature, e.g., when considering detector noise or in case of high photon counts, where Steidla a Mathematical Image Processing and Data Analysis Group, University of Kaiserslautern, Germany b of the reconstructed noise components follows the statistics of the assumed noise model. In this paper, we propose

  17. Problems on Non-Equilibrium Statistical Physics

    E-print Network

    Kim, Moochan

    2011-08-08

    Four problems in non-equilibrium statistical physics are investigated: 1. The thermodynamics of single-photon gas; 2. Energy of the ground state in Multi-electron atoms; 3. Energy state of the H2 molecule; and 4. The Condensation behavior in N...

  18. Learning Statistics By Doing Statistics

    NSDL National Science Digital Library

    Smith, Gary

    This article, created by Gary Smith of Pomona College, discusses a project-based approach to teaching statistics. The article focuses on the team aspect of learning, it introduces concepts such as: working with data, learning by doing, learning by writing, learning by speaking, and authentic assessment of material. An appendix contains a list of twenty projects that have been successfully assigned.

  19. Multiple photon emission in heavy particle decays

    NASA Technical Reports Server (NTRS)

    Asakimori, K.; Burnett, T. H.; Cherry, M. L.; Christl, M. J.; Dake, S.; Derrickson, J. H.; Fountain, W. F.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1994-01-01

    Cosmic ray interactions, at energies above 1 TeV/nucleon, in emulsion chambers flown on high altitude balloons have yielded two events showing apparent decays of a heavy particle into one charged particle and four photons. The photons converted into electron pairs very close to the decay vertex. Attempts to explain this decay topology with known particle decays are presented. Unless both events represent a b yields u transition, which is statistically unlikely, then other known decay modes for charmed or bottom particles do not account satisfactorily for these observations. This could indicate, possibly, a new decay channel.

  20. Photon counting processor for laser velocimetry

    NASA Technical Reports Server (NTRS)

    Mayo, W. T., Jr.

    1977-01-01

    In some of the more difficult applications of laser Doppler velocimetry such as in combustion research, transonic flow, transverse wind, and others, the optical signals are too small for classical detection methods. This paper summarizes the theory, experimental prototype hardware, and test results for a new type of high-speed photon-correlation signal processor which is being developed for weak laser velocimeter signals and other photon-resolved signals. The new system may also be considered to be a statistical digital frequency discriminator. It uses full multiplication with 10-nsec delay time and has the potential for extension to the measurement of the velocity correlations and spectra.

  1. U. S. Teenage Pregnancy Statistics

    NSDL National Science Digital Library

    The Alan Guttmacher Institute (AGI) is a nonpartisan organization that provides research, policy analysis, and public education about reproductive health. Recently, the AGI posted this special statistical report on teenage pregnancy in the US. The report consists of two large data tables synthesizing pregnancy statistics from 1972 to 1996. The first table provides the number of births, number of legal abortions, number of estimated miscarriages, and total number of pregnancies in the US between 1972 and 1996 for five different age distributions: fourteen or younger, fifteen to seventeen, eighteen to nineteen, fifteen to nineteen, and under twenty. The second table provides birth rates, abortion rates, and pregnancy rates per 1,000 women for the same years and age distributions as the first table. For both tables, data refer to the age of the women at time of pregnancy outcome, not at the time of conception. A list of statistical sources are included.

  2. Statistical mechanics of nonlinear elasticity Oliver Penrose

    E-print Network

    Penrose, Oliver

    Statistical mechanics of nonlinear elasticity Oliver Penrose Department of Mathematics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, Scotland, UK July 24, 2003 Running title: statistical mechanics Reviews classification numbers: 82B05 classical equilibrium statistical mechanics (general), 74B20

  3. ANTHROPOLOGICAL STATISTICS I THE UNIVERSITY OF TENNESSEE

    E-print Network

    Auerbach, Benjamin M.

    1 ANTHROPOLOGICAL STATISTICS I ANTH 504 THE UNIVERSITY OF TENNESSEE Instructor: Benjamin Auerbach Stadium Hall Course description: "There are three kinds of lies: lies, damn lies, and statistics." - Mark: statistics can be conducted on any set of numbers, but if the methods are used improperly, the results

  4. Quick statistics Survey 55563 'Privacy Survey'

    E-print Network

    Kaiser, Gail E.

    Quick statistics Survey 55563 'Privacy Survey' Results Survey 55563 Number of records in this query: 277 Total records in survey: 277 Percentage of total: 100.00% Page 1 / 94 #12;Quick statistics Survey 55563 'Privacy Survey' Page 2 / 94 #12;Quick statistics Survey 55563 'Privacy Survey' Field summary

  5. Singular statistics

    E-print Network

    E. Bogomolny; U. Gerland; C. Schmit

    2000-12-04

    We consider the statistical distribution of zeros of random meromorphic functions whose poles are independent random variables. It is demonstrated that correlation functions of these zeros can be computed analytically and explicit calculations are performed for the 2-point correlation function. This problem naturally appears in e.g. rank-one perturbation of an integrable Hamiltonian and, in particular, when a $\\delta$-function potential is added to an integrable billiard.

  6. Statistics I

    NSDL National Science Digital Library

    2013-06-21

    Students will encounter the concept of a distribution, along with parameters that describe a distribution's "typical" values (average) and a distribution's spread (variance). To understand simple distributions and uncertainty propagation in the coming sections, it is necessary to be familiar with the concept of statistical independence. When two variables fluctuate independently, their covariance vanishes, and the variance of their sum is the sum of their variances.

  7. BCSC Statistics

    Cancer.gov

    This section of the BCSC web site details the information collected and used in research by the BCSC. Statistics includes charts and tables that provide an overview of the data collected. These data are used in a wide range of studies that evaluate the performance of mammography in community settings. Some studies analyze data collected from individual sites; others examine data pooled from two or more sites.

  8. Leftist Numbers

    ERIC Educational Resources Information Center

    Rich, Andrew

    2008-01-01

    The leftist number system consists of numbers with decimal digits arranged in strings to the left, instead of to the right. This system fails to be a field only because it contains zerodivisors. The same construction with prime base yields the p-adic numbers.

  9. Number theory

    Microsoft Academic Search

    M. R. Schroeder

    1989-01-01

    Number theory, an abstract branch of mathematics that deals with relationships between whole numbers, has provided highly useful answers to numerous real-world problems. The author briefly reviews earlier uses of number theory and then examines recent applications to music, cryptography, and error-correction codes

  10. VOLUME 88, NUMBER 6 P H Y S I C A L R E V I E W L E T T E R S 11 FEBRUARY 2002 Waiting-Time Statistics of Self-Organized-Criticality Systems

    E-print Network

    Newman, David

    -Time Statistics of Self-Organized-Criticality Systems R. Sánchez,1,* D. E. Newman,2 and B. A. Carreras3 1- acteristics strikingly similar to those found in systems following the self-organized-criticality (SOC the threshold is locally overcome and the system then self- organizes itself via fast relaxation events

  11. VOLUME 82, NUMBER 9 P H Y S I C A L R E V I E W L E T T E R S 1 MARCH 1999 Statistical Properties of Genealogical Trees

    E-print Network

    Derrida, Bernard

    of Genealogical Trees Bernard Derrida,1 Susanna C. Manrubia,2 and Damián H. Zanette3 1 Laboratoire de Physique´o Negro, Argentina (Received 14 October 1998) We analyze the statistical properties of genealogical trees. By reconstructing the genealogy of an individual from the population evolution, we measure the distribution

  12. VOLUME 89, NUMBER 1 P H Y S I C A L R E V I E W L E T T E R S 1 JULY 2002 Statistical Theory of Asteroid Escape Rates

    E-print Network

    Ross, Shane

    of Asteroid Escape Rates Charles Jaffé,1,2,3 Shane D. Ross,1,2 Martin W. Lo,1,2 Jerrold Marsden,1 David to regulate the rate of escape of asteroids temporarily captured in circumplanetary orbits. The transition a statistical semianalytical theory for the rate of escape of asteroids temporarily captured by Mars. Theory

  13. Emitters of N-photon bundles

    NASA Astrophysics Data System (ADS)

    Muñoz, C. Sánchez; Del Valle, E.; Tudela, A. González; Müller, K.; Lichtmannecker, S.; Kaniber, M.; Tejedor, C.; Finley, J. J.; Laussy, F. P.

    2014-07-01

    Controlling the output of a light emitter is one of the basic tasks in photonics, with landmarks such as the development of the laser and single-photon sources. The ever growing range of quantum applications is making it increasingly important to diversify the available quantum sources. Here, we propose a cavity quantum electrodynamics scheme to realize emitters that release their energy in groups (or `bundles') of N photons (where N is an integer). Close to 100% of two-photon emission and 90% of three-photon emission is shown to be within reach of state-of-the-art samples. The emission can be tuned with the system parameters so that the device behaves as a laser or as an N-photon gun. Here, we develop the theoretical formalism to characterize such emitters, with the bundle statistics arising as an extension of the fundamental correlation functions of quantum optics. These emitters will be useful for quantum information processing and for medical applications.

  14. The Statistical Drake Equation

    NASA Astrophysics Data System (ADS)

    Maccone, Claudio

    2010-12-01

    We provide the statistical generalization of the Drake equation. From a simple product of seven positive numbers, the Drake equation is now turned into the product of seven positive random variables. We call this "the Statistical Drake Equation". The mathematical consequences of this transformation are then derived. The proof of our results is based on the Central Limit Theorem (CLT) of Statistics. In loose terms, the CLT states that the sum of any number of independent random variables, each of which may be ARBITRARILY distributed, approaches a Gaussian (i.e. normal) random variable. This is called the Lyapunov Form of the CLT, or the Lindeberg Form of the CLT, depending on the mathematical constraints assumed on the third moments of the various probability distributions. In conclusion, we show that: The new random variable N, yielding the number of communicating civilizations in the Galaxy, follows the LOGNORMAL distribution. Then, as a consequence, the mean value of this lognormal distribution is the ordinary N in the Drake equation. The standard deviation, mode, and all the moments of this lognormal N are also found. The seven factors in the ordinary Drake equation now become seven positive random variables. The probability distribution of each random variable may be ARBITRARY. The CLT in the so-called Lyapunov or Lindeberg forms (that both do not assume the factors to be identically distributed) allows for that. In other words, the CLT "translates" into our statistical Drake equation by allowing an arbitrary probability distribution for each factor. This is both physically realistic and practically very useful, of course. An application of our statistical Drake equation then follows. The (average) DISTANCE between any two neighboring and communicating civilizations in the Galaxy may be shown to be inversely proportional to the cubic root of N. Then, in our approach, this distance becomes a new random variable. We derive the relevant probability density function, apparently previously unknown and dubbed "Maccone distribution" by Paul Davies. DATA ENRICHMENT PRINCIPLE. It should be noticed that ANY positive number of random variables in the Statistical Drake Equation is compatible with the CLT. So, our generalization allows for many more factors to be added in the future as long as more refined scientific knowledge about each factor will be known to the scientists. This capability to make room for more future factors in the statistical Drake equation, we call the "Data Enrichment Principle," and we regard it as the key to more profound future results in the fields of Astrobiology and SETI. Finally, a practical example is given of how our statistical Drake equation works numerically. We work out in detail the case, where each of the seven random variables is uniformly distributed around its own mean value and has a given standard deviation. For instance, the number of stars in the Galaxy is assumed to be uniformly distributed around (say) 350 billions with a standard deviation of (say) 1 billion. Then, the resulting lognormal distribution of N is computed numerically by virtue of a MathCad file that the author has written. This shows that the mean value of the lognormal random variable N is actually of the same order as the classical N given by the ordinary Drake equation, as one might expect from a good statistical generalization.

  15. Bias-free true random-number generator

    Microsoft Academic Search

    Wei Wei; Hong Guo

    2009-01-01

    We propose a new approach to nondeterministic random number generation. In theory, the randomness originated from the uncorrelated nature of consecutive laser pulses with Poissonian photon number distribution and that of the consecutive single photon detections is used to generate random bit. In experiment, von Neumann correction method is applied to extract the final random bit. This method is proved

  16. String compactification, QCD axion and axion-photon-photon coupling

    E-print Network

    Kang-Sin Choi; Ian-Woo Kim; Jihn E. Kim

    2007-01-13

    It is pointed out that there exist a few problems to be overcome toward an observable sub-eV QCD axion in superstring compactification. We give a general expression for the axion decay constant. For a large domain wall number $N_{DW}$, the axion decay constant can be substantially lowered from a generic value of a scalar singlet VEV. The Yukawa coupling structure in the recent $Z_{12-I}$ model is studied completely, including the needed nonrenormalizable terms toward realistic quark and lepton masses. In this model we find an approximate global symmetry and vacuum so that a QCD axion results but its decay constant is at the GUT scale. The axion-photon-photon coupling is calculated for a realistic vacuum satisfying the quark and lepton mass matrix conditions. It is the first time calculation of $c_{a\\gamma\\gamma}$ in realistic string compactifications: $c_{a\\gamma\\gamma}={5/3}-1.93\\simeq -0.26$.

  17. Microwave photon antibunching at the modulation of the resonance frequency of a qubit emitter

    NASA Astrophysics Data System (ADS)

    Saiko, A. P.; Fedaruk, R.; Markevich, S. A.

    2015-02-01

    The statistics of photons in the resonance fluorescence of a qubit excited by microwave and radio-frequency (RF) fields have been studied. It has been established that the coherent dissipative dynamics of the qubit with allowance for multiphoton emission and absorption of RF photons in each act of emission and absorption of a microwave photon results in periodic alternation of photon bunching and antibunching. It has been shown that periodically varying statistics of photons can be smoothly transformed to the purely sub-Poisson statistics by varying the parameters of the RF field. The conditions for the formation of the "collapse-revival" of oscillations in the second-order correlation function of photons have been determined. The described effects can be implemented on spin and superconducting qubits, quantum dots, and qubit-mechanical hybrid systems.

  18. Single-photon detection timing jitter in a visible light photon counter

    E-print Network

    Baek, Burm; Stevens, Martin J; Kim, Jungsang; Hogue, Henry H; Nam, Sae Woo

    2009-01-01

    Visible light photon counters (VLPCs) offer many attractive features as photon detectors, such as high quantum efficiency and photon number resolution. We report measurements of the single-photon timing jitter in a VLPC, a critical performance factor in a time-correlated single-photon counting measurement, in a fiber-coupled closed-cycle cryocooler. The measured timing jitter is 240 ps full-width-at-half-maximum at a wavelength of 550 nm, with a dark count rate of 25 000 counts per second. The timing jitter increases modestly at longer wavelengths to 300 ps at 1000 nm, and increases substantially at lower bias voltages as the quantum efficiency is reduced.

  19. Single-Photon Detection Timing Jitter in a Visible Light Photon Counter

    NASA Astrophysics Data System (ADS)

    Baek, B.; McKay, K. S.; Stevens, M. J.; Kim, Jungsang; Hogue, H. H.; Nam, Sae Woo

    2010-06-01

    Visible light photon counters (VLPCs) offer many attractive features as photon detectors, such as high quantum efficiency and photon number resolution. We report measurements of the single-photon timing jitter in a VLPC, a critical performance factor in a time-correlated single-photon counting measurement, in a fiber-coupled closed-cycle cryocooler. The measured timing jitter is 240 ps full-width-at-half-maximum at a wavelength of 550 nm, with a dark count rate of 25 000 counts per second. The timing jitter increases modestly at longer wavelengths to 300 ps at 1000 nm, and increases substantially at lower bias voltages as the quantum efficiency is reduced.

  20. Photons from Heavy-Ion Collisions at Fermi Velocity

    E-print Network

    Ko, Che Ming; Alchelin, J.

    1987-01-01

    'I ~ (+l Ii & & .~ I + I I 'f Il I I PHYSICAL REVIEW C VOLUME 35, NUMBER 5 MAY 1987 Photons from heavy-ion collisions at Fermi velocity Che Ming Ko Center for Theoretical Physics, Physics Department and Cyclotron Institute, Texas Ad... December 1986) The production of photons from heavy-ion collisions at intermediate energies is studied in the model based on the Boltzmann-Uehling-Uhlenbeck equation. Taking into account photon produc- tion from nucleon-nucleon collisions...

  1. Investigation of Ti\\/Pd Bilayer for Single Photon Detection

    Microsoft Academic Search

    Emanuele Taralli; Chiara Portesi; Roberto Rocci; Mauro Rajteri; Eugenio Monticone

    2009-01-01

    Transition-edge sensor (TES) microcalorimeters are promising for application in the field of quantum information and quantum computation thanks to their outstanding single photon detection capabilities. Good energy resolution and photon number discrimination at visible and near-infrared wavelengths make them extensively used as single photon detectors. In this work we report details on the fabrication of Pd\\/Ti TESs deposited by e-beam

  2. Large-scale production techniques for photonic nanostructures

    Microsoft Academic Search

    Wim Bogaerts; Vincent Wiaux; Pieter Dumon; Dirk Taillaert; Johan Wouters; Stephan Beckx; Joris Van Campenhout; Bert Luyssaert; Dries Van Thourhout; Roel Baets

    2003-01-01

    Nanophotonic ICs promise to play a major role in the future of opto-electronic signal processing and telecommunications. But for these devices, which consist of large numbers of wavelength-scale photonic components, to be successful, reliable and cost-effective mass-fabrication technology is needed. Photonic components, and among them photonic crystals, require a high degree of accuracy, which translates to low fabrication tolerances. Today,

  3. Real time statistical field theory

    E-print Network

    M. E. Carrington; T. Fugleberg; D. S. Irvine; D. Pickering

    2006-08-28

    We have written a {\\it Mathematica} program that calculates the integrand corresponding to any amplitude in the closed-time-path formulation of real time statistical field theory. The program is designed so that it can be used by someone with no previous experience with {\\it Mathematica}. It performs the contractions over the tensor indices that appear in real time statistical field theory and gives the result in the 1-2, Keldysh or RA basis. We have used the program to calculate the ward identity for the QED 3-point function, the QED 4-point function for two photons and two fermions, and the QED 5-point function for three photons and two fermions. In real time statistical field theory, there are seven 3-point functions, 15 4-point functions and 31 5-point functions. We produce a table that gives the results for all of these functions. In addition, we give a simple general expression for the KMS conditions between $n$-point green functions and vertex functions, in both the Keldysh and RA bases

  4. Methodological and Statistical Problems in Uvulopalatopharyngoplasty Research

    Microsoft Academic Search

    Uchechukwu C. Megwalu; Jay F. Piccirillo

    Results: Overall, the articles demonstrated fair meth- odological and statistical quality. Compared with the pre- vious review by Schechtman et al, there was a slight in- crease in the number of articles that discussed statistical power and reported confidence intervals. There were in- creases in the mean sample size, the percentage of ran- domized controlled studies, the number of end

  5. VOLUME 76, NUMBER 8 P HY S I CA L REV I EW L E T T ER S 19 FEBRUARY 1996 Quantum Optical SpinGlass State of Impurity TwoLevel Atoms in a Photonic Band Gap

    E-print Network

    John, Sajeev

    long­ range nature of RDDI, this state is the quantum optical analog of a classical neural network [7VOLUME 76, NUMBER 8 P HY S I CA L REV I EW L E T T ER S 19 FEBRUARY 1996 Quantum Optical Spin at a given site is nonzero. Glassy behavior may also arise in quantum systems. Interacting electrons

  6. Jet energy scale setting with "photon+Jet" events at LHC energies. Selection of events with a clean "photon+Jet" topology and photon Pt - jet Pt disbalance

    E-print Network

    D. V. Bandourin; V. F. Konoplyanikov; N. B. Skachkov

    2001-04-27

    It is shown in the paper that Pt activity limitation (modulus of the vector sum) of all particle beyond "photon+Jet" system Pt^out leads to the noticeable photon Pt - jet Pt disbalance decreasing. On a simultaneous restriction of the cluster Pt and Pt^out from above it is possible to reach an acceptable balance between photon Pt - jet Pt with a sufficient number of the photon Pt - jet Pt events for the jet energy scale setting and hadron calorimeter calibratiom of the CMS detector at LHC.

  7. Thiophene dendrimers as entangled photon sensor materials.

    PubMed

    Harpham, Michael R; Süzer, Ozgün; Ma, Chang-Qi; Bäuerle, Peter; Goodson, Theodore

    2009-01-28

    The ability to do spectroscopy with a small number of entangled photons is an important development in the area of materials and sensing. This report investigates the effects of increasing thiophene dendrimer generation on the cross-section for both entangled (sigmaE) and random (deltaE) two-photon absorption cross-sections. Nonlinear optical properties of dendrimers are an interesting area of study because of potential applications in optical signal processing and remote sensing, and the use of a nonlinear optical material as a sensor for entangled photons offers great possibilities for applications in quantum lithography. Entangled two-photon absorption (ETPA) experiments and two-photon excited fluorescence (TPEF) experiments vary by at least 10 orders of magnitude in the photon flux used to probe the material. ETPA cross-sections from liquid samples as well as those of thin-film samples are investigated. An increase in sigmaE and de;taR with increasing dendrimer generation is observed, suggesting that the thiophene groups within the dendrimer nonlinearly absorb in a cooperative manner, which is further evidenced in the variation of cross-section per thiophene group. The nonlinear spectroscopic features obtained by the TPEF measurements were also obtained by the ETPA experiments, despite the fact that 10 orders of magnitude fewer photons are used in the latter technique. All dendrimer generations investigated in this work are found to have great potential for applications in quantum optical devices. PMID:19123819

  8. Study of squeezed state on free electron lasers 1 Work supported by the Office of Naval Research under grant Number N00014-94-1-0818. 1

    Microsoft Academic Search

    Teng Chen; J. M. J. Madey

    1998-01-01

    Preliminary investigations on squeezed state of FEL have been undertaken at the Duke FEL lab by means of photon counting experiments. We report photon statistics for spontaneous undulator radiation from Duke Storage Ring. Photon counting measurements have also been constructed on the Mark III FEL to obtain the statistical behavior of the visible harmonics of the infrared radiation. The initial

  9. QUANTUM STATISTICAL CORRECTIONS TO ASTROPHYSICAL PHOTODISINTEGRATION RATES

    SciTech Connect

    Mathews, G. J. [Center for Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Pehlivan, Yamac [Mimar Sinan Fine Arts University Besiktas, Istanbul 34349 (Turkey); Kajino, Toshitaka [National Astronomical Observatory of Japan 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 (Japan); Balantekin, A. B. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Kusakabe, Motohiko, E-mail: gmathews@nd.edu, E-mail: yamac@physics.wisc.edu, E-mail: kajino@nao.ac.jp, E-mail: baha@physics.wisc.edu, E-mail: kusakabe@icrr.u-tokyo.ac.jp [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

    2011-01-20

    Tabulated rates for astrophysical photodisintegration reactions make use of Boltzmann statistics for the photons involved as well as the interacting nuclei. Here, we derive analytic corrections for the Planck-spectrum quantum statistics of the photon energy distribution. These corrections can be deduced directly from the detailed balance condition without the assumption of equilibrium as long as the photons are represented by a Planck spectrum. Moreover, we show that these corrections affect not only the photodisintegration rates but also modify the conditions of nuclear statistical equilibrium as represented in the Saha equation. We deduce new analytic corrections to the classical Maxwell-Boltzmann statistics which can easily be added to the reverse reaction rates of existing reaction network tabulations. We show that the effects of quantum statistics, though generally quite small, always tend to speed up photodisintegration rates and are largest for nuclei and environments for which Q/kT {approx} 1. As an illustration, we examine possible effects of these corrections on the r-process, the rp-process, explosive silicon burning, the {gamma}-process, and big bang nucleosynthesis. We find that in most cases one is quite justified in neglecting these corrections. The correction is largest for reactions near the drip line for an r-process with very high neutron density, or an rp-process at high temperature.

  10. Simulations of avalanche breakdown statistics: probability and timing

    Microsoft Academic Search

    Jo Shien Ng; Chee Hing Tan; John P. R. David

    2010-01-01

    Important avalanche breakdown statistics for Single Photon Avalanche Diodes (SPADs), such as avalanche breakdown probability, dark count rate, and the distribution of time taken to reach breakdown (providing mean time to breakdown and jitter), were simulated. These simulations enable unambiguous studies on effects of avalanche region width, ionization coefficient ratio and carrier dead space on the avalanche statistics, which are

  11. Avalanche photodiode detection statistics for direct detection laser radar

    Microsoft Academic Search

    Douglas G. Youmans

    1992-01-01

    The detection statistics of avalanche photodiode detectors when used in laser radar systems are examined. In the laser radar systems considered here, a diffuse hard target is illuminated by a transmitted laser beam and the photons subtended by the receiving aperture and focused onto the detector obey negative-binomial statistics. The specific negative-binomial distribution is determined by the coherence length of

  12. Spike statistics

    E-print Network

    J. Mark Heinzle; Claes Uggla

    2012-12-21

    In this paper we explore stochastical and statistical properties of so-called recurring spike induced Kasner sequences. Such sequences arise in recurring spike formation, which is needed together with the more familiar BKL scenario to yield a complete description of generic spacelike singularities. In particular we derive a probability distribution for recurring spike induced Kasner sequences, complementing similar available BKL results, which makes comparisons possible. As examples of applications, we derive results for so-called large and small curvature phases and the Hubble-normalized Weyl scalar.

  13. CT number definition

    NASA Astrophysics Data System (ADS)

    Bryant, J. A.; Drage, N. A.; Richmond, S.

    2012-04-01

    The accuracy of CT number plots has been found lacking in several medical applications. This is of concern since the ability to compare and evaluate results on a reproducible and standard basis is essential to long term development. Apart from the technical limitations arising from the CT scanner and the data treatment, there are fundamental issues with the definition of the Hounsfield number, namely the absence of a standard photon energy and the need to specify the attenuation mechanism for standard measurements. This paper presents calculations to demonstrate the shortcomings of the present definition with a brief discussion. The remedy is straightforward, but probably of long duration as it would require an international agreement.

  14. Superdense teleportation using hyperentangled photons.

    PubMed

    Graham, Trent M; Bernstein, Herbert J; Wei, Tzu-Chieh; Junge, Marius; Kwiat, Paul G

    2015-01-01

    Transmitting quantum information between two remote parties is a requirement for many quantum applications; however, direct transmission of states is often impossible because of noise and loss in the communication channel. Entanglement-enhanced state communication can be used to avoid this issue, but current techniques require extensive experimental resources to transmit large quantum states deterministically. To reduce these resource requirements, we use photon pairs hyperentangled in polarization and orbital angular momentum to implement superdense teleportation, which can communicate a specific class of single-photon ququarts. We achieve an average fidelity of 87.0(1)%, almost twice the classical limit of 44% with reduced experimental resources than traditional techniques. We conclude by discussing the information content of this constrained set of states and demonstrate that this set has an exponentially larger state space volume than the lower-dimensional general states with the same number of state parameters. PMID:26018201

  15. Tissue characterization with ballistic photons

    NASA Astrophysics Data System (ADS)

    Strojnik, Marija; Paez, Gonzalo

    2009-08-01

    We propose tissue characterization with ballistic photons, those whose direction or propagation speed is not affected by the presence of tissue. The most critical aspect of the tissue characterization problem is calibration of experimental measurements. The calibration method relates the fringe irradiance (power modulation in one interferometer arm) with the sample concentration under controlled conditions. During this step, the absorption and scattering indices ?a and ?sc are determined as a function of concentration for each material or tissue of interest, using a set of containers to vary travel distance D. It is assumed that linear scattering coefficient, ksc (absorption coefficient, ?a), is proportional to the number of scattering particles per unit volume, or particle concentration, c, in [ml/l]. Attenuation is proportional to concentration of scattering (absorption) centers and the sample length. The sensitivity of method is estimated at 10-19 with uncoated plate beam-splitters and intensified photon-counting detector.

  16. Superdense teleportation using hyperentangled photons

    PubMed Central

    Graham, Trent M.; Bernstein, Herbert J.; Wei, Tzu-Chieh; Junge, Marius; Kwiat, Paul G

    2015-01-01

    Transmitting quantum information between two remote parties is a requirement for many quantum applications; however, direct transmission of states is often impossible because of noise and loss in the communication channel. Entanglement-enhanced state communication can be used to avoid this issue, but current techniques require extensive experimental resources to transmit large quantum states deterministically. To reduce these resource requirements, we use photon pairs hyperentangled in polarization and orbital angular momentum to implement superdense teleportation, which can communicate a specific class of single-photon ququarts. We achieve an average fidelity of 87.0(1)%, almost twice the classical limit of 44% with reduced experimental resources than traditional techniques. We conclude by discussing the information content of this constrained set of states and demonstrate that this set has an exponentially larger state space volume than the lower-dimensional general states with the same number of state parameters. PMID:26018201

  17. Investigating the Randomness of Numbers

    ERIC Educational Resources Information Center

    Pendleton, Kenn L.

    2009-01-01

    The use of random numbers is pervasive in today's world. Random numbers have practical applications in such far-flung arenas as computer simulations, cryptography, gambling, the legal system, statistical sampling, and even the war on terrorism. Evaluating the randomness of extremely large samples is a complex, intricate process. However, the…

  18. National Statistical Service of Greece

    NSDL National Science Digital Library

    Greece is one of the oldest countries in the world, and for those seeking current and historical information about the country in terms of a variety of statistics, this website will be quite useful. On the site, visitors can download a recent publication titled "Greece in Numbers" which is a 27-page document produced by the Statistical Service that features some basic demographic data, along with information about the country's manufacturing output and natural resources. Within the section titled "Statistical Data", visitors can also view more specialized data such as yearly information about the number of live births and the labor market. Visitors looking to learn about the new products released on the site should consult the "News" section or read through their press release section as well for various statistical indices.

  19. SOCR: Statistics Online Computational Resource

    PubMed Central

    Dinov, Ivo D.

    2011-01-01

    The need for hands-on computer laboratory experience in undergraduate and graduate statistics education has been firmly established in the past decade. As a result a number of attempts have been undertaken to develop novel approaches for problem-driven statistical thinking, data analysis and result interpretation. In this paper we describe an integrated educational web-based framework for: interactive distribution modeling, virtual online probability experimentation, statistical data analysis, visualization and integration. Following years of experience in statistical teaching at all college levels using established licensed statistical software packages, like STATA, S-PLUS, R, SPSS, SAS, Systat, etc., we have attempted to engineer a new statistics education environment, the Statistics Online Computational Resource (SOCR). This resource performs many of the standard types of statistical analysis, much like other classical tools. In addition, it is designed in a plug-in object-oriented architecture and is completely platform independent, web-based, interactive, extensible and secure. Over the past 4 years we have tested, fine-tuned and reanalyzed the SOCR framework in many of our undergraduate and graduate probability and statistics courses and have evidence that SOCR resources build student’s intuition and enhance their learning. PMID:21451741

  20. Number Sense

    NSDL National Science Digital Library

    Mrs. Black

    2007-10-03

    Students will practice counting to 100 and making numbers with base ten blocks Let\\'s have some fun with math! First, practice counting to 100. Listen to the instructions on this website. Count to 100 Now that you have worked on counting to 100, let\\'s make some numbers! Use the base ten blocks to make the numbers shown on the screen! Base Ten Blocks Great work! The next ...