The experimental demonstration of the Josephson effect is a direct manifestation of the quantum phase of the superconductive order parameter and of the coupling of this phase to the electromagnetic field. The ac Josephson effect links the time evolution o...

Based on the differences between superfluid helium and superconductors in the dissipation mechanism of a weakly coupled system, an attempt is made to explain the possibility of observing an ac Josephson effect in superfluid helium with an orifice much larger than the coherence length of the superfluid helium. The temperature criterion ...

The magnetic field dependence of the maximum dc Josephson current and of the ac Josephson-effect-induced step structure has been measured for sputter Nb--NbO/sub x/--Pb Josephson junctions and found to be in very good agreement with theoretical predictions, even for junctions made with 'dirty' Nb ...

We report the first observations of the a.c. and d.c. Josephson effects in a single BEC Josephson junction [1]. We also measure the chemical potential -- current relation of the BEC Josephson junction. The coherent tunneling of the BEC is qualitatively altered by the thermal cloud, whose ...

Experiments utilizing the ac Josephson effect already provide a precise means of monitoring the stability of some of the nationally maintained standards of voltage. The advantages to be gained from operating most components of such a system at cryogenic t...

An experiment is proposed which will investigate any possible dependence of the superconducting flux quantum on material. The time variation of the circulating supercurrent in a ring containing two Josephson junctions is discussed, taking into account the...

We analyze the dc and ac Josephson effects in SaINISb junctions in which an additional bias current flows in the N layer. The case of low temperatures and voltages \\(eV, T<Josephson current may change sign, and the considered SINIS junction ...

In this article we comment on the relation between the ac Josephson effect and the coherent oscillations of a Bose-Einstein condensate confined to a double-well potential. The goal is to elucidate the extent to which the latter is a realization of the former. We detail the correspondence between the two oscillation frequencies, that ...

... AC susceptibility measurements near the critical temperature of a Y-Ba-Cu-O superconductor, in: "High Temperature Superconductors," DU ...

We have performed a variety of precision measurements by comparing ac and dc waveforms generated by two independent ac programmable Josephson voltage standard (ACPJVS) systems. The objective of these experiments was to demonstrate the effectiveness of using a sampling digital voltmeter to measure small differences ...

We have performed a variety of precision measurements by comparing ac and dc waveforms generated by two independent ac programmable Josephson voltage standard (ACPJVS) systems. The objective of these experiments was to demonstrate the effectiveness of using a sampling digital voltmeter to measure small differences ...

The detection of the ac Josephson current in Nb microbridges with dimensions larger than the coherence length but smaller than the effective penetration depth is reported at frequencies between 1.7 and 180 GHz. Precise Josephson linewidth measurements are performed as a function of dc bias and frequency and the ...

We develop a theory for the AC Josephson effect in 2-gap intrinsic Josephson junction stacks. The coupled dynamical equations which the phase differences obey are derived from the phenomenological effective Lagrangian. The equations can describe the longitudinal Josephson ...

Experiments searching for the AC Josephson effect in superfluid /sup 3/He, analogous to phenomena observed in superconducting microbridges, have been performed. Measurements of this type test the fundamental properties of the superfluid described by a macroscopic wave function. Small orifices were employed as the weak link between two ...

We have measured the ac Josephson effect in small-area superconducting tunnel junctions at 604 GHz (lambda = 496 ..mu..m) using a resonant planar dipole antenna to couple the radiation into the junction. In a 176-..cap omega.. junction, we have observed up to the 7th Josephson step (at 8.75 mV), a performance ...

We propose a threshold detector with an operating principle based on a parametric period-doubling bifurcation in an externally pumped nonlinear resonance circuit. The ac-driven resonance circuit includes a dc-current�biased Josephson junction ensuring parametric frequency conversion (period-doubling bifurcation) due to its quadratic nonlinearity. A sharp ...

Intrinsic current steps in the I-V characteristics of thin film superconducting bridges were observed using a dielectric rutile resonator as a high-Q resonator. It is shown that the observation of these steps proves the existence of the ac Josephson effect in these bridges. (MHR)

Pure spin currents can be injected and detected in conductors via ferromagnetic contacts. We consider the case when the conductors become superconducting. A dc pure spin current flowing in one superconducting wire toward another superconductor via a ferromagnet contact induces ac voltage oscillations caused by Josephson tunneling of condensate electrons. ...

ac Josephson effect in one-dimensional Tomonaga-Luttinger liquid (TLL) adiabatically connected to superconducting electrodes is theoretically investigated. It is found that density fluctuations due to repulsive electron-electron interactions in TLL inhibit Josephson oscillations, whereas they do not affect ...

We describe an optical system that allows for direct observation of the photonic Josephson effects in two weakly linked microcavities containing ultracold two-level atoms. We show that, by moving the ultracold atoms within one cavity, we could simulate an analogous superconducting circuit and realize both the alternating- and direct-current ...

Subterahertz radiation emitted from a variety of short rectangular-, square-, and disk-shaped mesas of intrinsic Josephson junctions fabricated from a Bi2Sr2CaCu2O8+? single crystal was studied from the observed I-V characteristics, far-infrared spectra, and spatial radiation patterns. In all cases, the radiation frequency satisfies the conditions both for the ...

We present experiments on photon-assisted tunneling and ac Josephson effect using microwaves in an energy range 1.05

We report on the observation of spontaneous coherent oscillations in a microcavity polariton bosonic Josephson junction. Condensation of exciton polaritons here takes place under incoherent excitation in a double potential well naturally formed in the disorder. Coherent oscillations set on at an excitation power well above the condensation threshold. The time resolved ...

We report on the observation of spontaneous coherent oscillations in a microcavity polariton bosonic Josephson junction. Condensation of exciton polaritons here takes place under incoherent excitation in a double potential well naturally formed in the disorder. Coherent oscillations set on at an excitation power well above the condensation threshold. The time resolved ...

We report on the observation of spontaneous coherent oscillations in a microcavity polariton bosonic Josephson junction. Condensation of exciton polaritons here takes place under incoherent excitation in a double potential well naturally formed in the disorder. Coherent oscillations set on at an excitation power well above the condensation threshold. The time resolved ...

Experimental equipment and measurement procedures are described which are used in developing a primary voltage standard based on the ac Johnson effect in order to link the national voltage unit to the universal constant 2 e/h. Use was made of niobium poin...

We present a dynamical theory for the phase differences along a stacked direction of intrinsic Josephson junctions (IJJ's) in layered multigap superconductors, motivated by the discovery of highly anisotropic iron-based superconductors with thick perovskite-type blocking layers. The dynamical equations describing ac and dc intrinsic ...

We present a dynamical theory for the phase differences along a stacked direction of intrinsic Josephson junctions (IJJ�s) in layered multigap superconductors, motivated by the discovery of highly anisotropic iron-based superconductors with thick perovskite-type blocking layers. The dynamical equations describing ac and dc intrinsic ...

The simple theory of the ac Josephson effect in a tunnel junction is presented and recent work on the development and implementation of a national voltage standard based on measurements of the fundamental physical constant 2e/h is reviewed. The principle ...

Enhancement of the critical current of clean point contacts made of bulk superconducting aluminum is measured when the contacts are in a 1--10 GHz microwave field. This enhancement interferes with the ac Josephson effect. (AIP)

Detailed measurements of the second sound excess attenuation in vertical counter flow show the existence of a zero critical velocity and of steps which can be interpreted as a Josephson ac effect related to vortex motion. (auth)

This document reports the first observations of photon-assisted quasiparticle tunneling and AC Josephson effect in superconducting tunnel junctions irradiated with far-infrared radiation.

We propose a new technique for accurate measurement of ac voltages with Josephson junctions. Based on the counting of pulses generated by a Josephson junction, the method may be capable of precision at the ppm level for frequencies less than 100 kHz.

I propose a new mechanism of intense high-frequency electromagnetic wave generation by spatially uniform stacked Josephson junctions at zero magnetic field. The ac-Josephson effect converts the dc-bias voltage into ac supercurrent; however, in the absence of spatial variation of the Josephson ...

The quantum Smoluchowski equation for the reduced Wigner function in configuration space pertaining to the quantum Brownian motion of a particle in a tilted cosine potential in the high dissipation (or noninertial) limit as applied to a model point Josephson junction (namely, a resistively shunted junction in the presence of noise and an arbitrarily large microwave ...

The ac Josephson effect provides a convenient source of electromagnetic oscillations which are voltage-tunable according to the relation f = 2eV/h. In principle, the frequency of oscillation can be anything from zero to a few terahertz for junctions made of lead- or niobium-based superconductors. In practice, the available power of a ...

Experimental equipment and measurement procedures are described which are used in developing a primary voltage standard based on the ac Johnson effect in order to link the national voltage unit to the universal constant 2 e/h. Use was made of niobium point Josephson junctions producing a voltage of about 1 mV. This voltage was measured ...

We have measured the ac Josephson effect in Nb point contacts at 604 GHz (496 ..mu..m). We find the coupling of the far-infrared radiation to the point contact to depend in a simple manner on the resistance of the contact. The behavior of the high-resistance point contacts (50< or =R< or =200 ..cap omega..) is very reproducible, ...

We have studied niobium point contacts which are very consistent and reproducible from junction to junction, in both their dc and high-frequency behavior. We find a strong correlation between the sharpness of the gap structure and the ac Josephson effect, and we present the first quantitative measurements of the far-infrared frequency ...

I solve numerically a full set of nonlinear kinetic balance equations for stacked Josephson junctions, which allows analysis of strongly nonequilibrium phenomena. It is shown that nonlinearity becomes significant already at very small disequilibrium. The following new, nonlinear effects are obtained: (i) At even-gap voltages V=2n?/e (n=2,3,�) ...

We calculate the ac and dc current-voltage (I-V) relation when a tunnel barrier is placed in the normal region of a superconductor{endash}normal-metal{endash}superconductor (S{sub 1}NS{sub 2}) junction, where the two superconducting contacts have different gaps ({Delta}{sub 2}{ge}{Delta}{sub 1}{ge}0). The voltages at which subharmonic gap structure (SGS) appears in the ...

The influence of microwave phase noise on rf-induced constant voltage steps generated by the ac Josephson effect is studied. Different circuit models for the junction excitation are considered: dc and rf voltage generators, dc and rf current generators, dc current and rf voltage generators. The analysis has been carried out assuming a ...

We consider a nanoelectromechanical Josephson junction, where a suspended nanowire serves as a superconducting weak link, and show that an applied dc bias voltage can result in suppression of the flexural vibrations of the wire. This cooling effect is achieved through the transfer of vibronic energy quanta first to voltage-driven Andreev states and then to ...

We consider a nanoelectromechanical Josephson junction, where a suspended nanowire serves as a superconducting weak link, and show that an applied dc bias voltage can result in suppression of the flexural vibrations of the wire. This cooling effect is achieved through the transfer of vibronic energy quanta first to voltage-driven Andreev states and then to ...

We propose a new method to create an asymmetric two-dimensional magnetic lattice which exhibits magnetic band gap structure similar to semiconductor devices. The quantum device is assumed to host bound states of collective excitations formed in a magnetically trapped quantum degenerate gas of ultracold atoms such as a Bose-Einstein condensate (BEC) or a degenerate Fermi gas. A theoretical ...

A simple explanation, via a pendulum analogy, is given for the Josephson effect. Uses of Josephson junctions and SQUIDs are discussed.(AIP)

YBa/sub 2/Cu/sub 3/O/sub 7-x/ thick films were fabricated by the method of screen printing. A zero resistance state was achieved at 90K. The highest critical current density was about 150 A/cm/sup 2/ at 77K. Bridge type Josephson junction and dc SQUID were fabricated from thick films and operated at 77K. The induced steps produced by the ac ...

A new ac loss behaviour is observed in the superconducting state of Bi(2)Sr(2)CaCu(2)O(8) single crystals using a novel technique of measuring dissipation at radio frequencies. It is found that�the ac loss in the superconducting state is larger than that in the normal state. This counter-intuitive result is explained in terms of the cumulative ...

A detailed numerical study on the directed motion of ac-driven vortices and antivortices in 2D Josephson junction arrays with an asymmetric periodic pinning potential is reported. dc-voltage rectification shows a strong dependence on vortex density as well as an inversion of the vortex flow direction with ac amplitude for a wide range ...

We investigate the ac Josephson effect in superconductor-graphene-superconductor (SGS) junctions by using the Floquet-Green's function formalism to solve the Dirac-Bogoliubov-de Gennes equation. The numerical results show rich subharmonic gap structures such as the negative differential conductance (NDC) in the dc current. The ...

In this paper we study the Josephson tunneling for a quantum fluid (a Bose-Einstein condensate) in the presence of a weak gravitational wave. Starting from a Lagrangian formulation in the framework of linearized gravity, we deduce the Gross-Pitaevskii equation for the fluid in a weak gravitational background. We use such an equation to investigate the influence of a ...

The Josephson junction is the only radio-frequency electrical element which can be both non-dissipative and non-linear at low temperatures. While the stability of the junction dynamics in presence of a DC drive has been extensively studied, the microwave drive case is relatively poorly understood, at least experimentally. It is explored by driving an increasing ...

Low-frequency ac currents have been observed to induce a dc voltage {ital V}{sub dc} across macroscopic percolating films of lead and aluminum in the vicinity of their superconducting transition. This conversion is observed down to a frequency of 10 Hz, which rules out an inverse-Josephson-effect interpretation. {ital V}{sub dc} shows sharp oscillations as ...

We have investigated PAT (Photon-AssistedTunneling) effect induced by SMMW (Submillimeter-Wave) in SIS point-contacts with an insulating barrier containing magnetic impurities: a magnetic barrier. The junctions turned out to have severely suppressed dc and ac Josephson currents, which makes them promising junctions for a high frequency ...

Experiments based on an analogy to the ac Josephson effect have shown in both $sup 3$He-A and $sup 3$He-B that a pairing theory of the superfluidity of $sup 3$He is essentially correct. Additional observations of parallel ringing are not in agreement with the simple ''pendulum models'' used to ...

The AC susceptibility, ?, at zero DC magnetic field of a polycrystalline sample of LaFeAsO0.94F0.06 ( T c ?24 K) has been investigated as a function of the temperature, the amplitude of the AC magnetic field (in the range H ac =0.003 Oe�4 Oe) and the frequency (in the range f=10 kHz�100 kHz). The ?( T) curve exhibits the typical ...

Contents: NBS to maintain U.S. legal volt using 2e/h via the AC Josephson effect; NBS and the development of computer technology; NSRDS news; High-accuracy spectrophotometry; High-precision rotary-vane attenuator; Laser beam tests pressure transducers; Co...

The nature of the low frequency plasma in cuprate superconductors and the electromagnetic phenomena related to the plasma excitation are theoretically studied. The interaction of electromagnetic wave with the transverse part of the low frequency plasma causes a peculiar frequency and magnetic field dependence of the reflectivity and transmissivity for a film of cuprate superconductor. It is ...

We have frequency analyzed the voltage oscillation of a current-biased resistively lshunted Josephson-junction (RSJ) model. In particular we have been interested in the situation where there is an ac (microwave) -induced step in the I-V characteristic. Conversion of the Josephson oscillation into other frequency modes is studied under ...

The Josephson effect is generally described as Cooper-pair tunneling but it can also be understood in a more general context. The dc Josephson effect is the pseudo-Goldstone boson of two coupled systems with a broken continuous Abelian U(1) symmetry. Hence, an analog should exist for systems with broken ...

Image-force effects in normal state tunneling through lead-oxide-lead junctions exhibiting Josephson

The power of direct tunable radiation into free space induced by Josephson oscillations in intrinsic Josephson junctions of highly anisotropic layered superconductors is derived. The super-radiation regime in a current biased crystal is considered when no dc magnetic field is applied. It is assumed that crystal is cut in the form of thin plate parallel to ...

The high-frequency behavior of niobium cat-whisker point contacts has been studied using radiation from an optically pumped far-infrared laser. When the point contacts are classified on the basis of their high-frequency performance, their dc I-V curves fall into recognizable groups. We find that the ac Josephson effect has a strong ...

... Accession Number : ADA001027. Title : Noise in Josephson Effect mm-Wave Mixers,. Corporate Author : CALIFORNIA UNIV ...

... Accession Number : ADA201483. Title : Josephson Effect Research in High-Temperature Superconductors. Descriptive Note : Interim rept. ...

The Ginzburg-Landau equation is used to investigate the Josephson effect in superconductive tunnelling in which condensed electron pairs tunnel through the barrier. (C.E.S.)

We demonstrate that the two-level atomic picture of the Josephson effect is valid for realistic tunneling models. In addition, we extend the analogy between two-level quantum systems and Josephson junctions to include stimulated emission and absorption processes. (AIP)

We have measured the far-infrared frequency dependence of the strength of the ac Josephson effect in Nb cat-whisker point contacts, which have consistent and reproducible behavior and minimal extrinsic high-frequency limitations due to capacitance and heating. We monitor the constant-voltage Josephson steps induced ...

Josephson effects are macroscopic quantum phenomena that can be understood at the undergraduate level with the help of mechanical analogs. Although Josephson junctions in zero magnetic field can be modeled by pendulum analogs, a simple mechanical model of Josephson junctions in nonzero fields has been elusive. We ...

The macroscopic quantum effects in superconducting point contacts weakly connecting two superconductors are described. In the case of a single point contact attention is paid to the resistivesuperconductive region, the current-- voltage characteristic and the radiative properties. The point contact is treated using a twofluid model in which the total current is the ...

We theoretically study the macroscopic quantum tunneling (MQT) in a hetero Josephson junction formed by a conventional single-gap superconductor and a multigap superconductor such as iron-based superconductors and MgB2. In such a Josephson junction more than one phase difference is defined. We clarify their phase dynamics and construct a theory for the MQT ...

Spielman et al. [Phys. Rev. Lett. 84, 5808 (2000] recently observed a large and sharp Josephson-like zero-bias peak in the tunnel conductance of a bilayer system in a quantum Hall ferromagnet state. We argue that disorder-induced topological defects in the pseudospin order parameter limit the peak size and destroy the predicted Josephson ...

We have performed a systematic study of planar thin film YBCO weak links fabricated using nanolithography and a conventional 200 keV ion implanter. The samples showed clear d.c. and a.c. Josephson effects. Supercurrent modulation of up to 65% of the maximum Ic at 77 K was observed for small applied magnetic fields. Irradiation of a ...

We consider a system of two semifluxons of opposite polarity in a 0-?-0 long Josephson junction, which classically can be in one of two degenerate states: ?? or ??. When the distance a between the 0-? boundaries (semifluxon�s centers) is a bit larger than the crossover distance ac , the system can switch from one state to the other due to thermal ...

Studies have been carried out to develop methods to couple Josephson junction oscillators at frequencies near 100GHz so as to demonstrate the feasibility of Josephson effect sources of reasonable power and impedance. Phase-locking of junctions separated b...

An expression for the oscillatory part of the Josephson current in a short superconducting contact is obtained in the high-voltage limit (V>>..delta..).

Josephson junctions with an antiferromagnetic metal as a link are described. The junction can be switched off by a relatively small magnetic field. The amplitude of the current oscillates as a function of the field.

... TITLE (lInclude Security Clauificationl Experimental Studies of Josephson ... we began work to test predictions that macroscopic ... 0 ~ 03 Mj o. '6 2 - ->, l ...

... [16] (Attached) 3. Investigation of Josephson interferometer potentials by ac excitations, Ref ... Figure 2. Power spectrum of femtosecond laser pulse ...

The dc voltage output from an hysteretic Josephson junction which is locked to an ac frequency source differs from the ideal Josephson relation if the junction drives a current about a closed superconducting circuit. The difference in voltage (Delta)V fro...

We have fabricated Nb/sub 3/Ge/amorphous-silicon/Pb Josephson tunnel junctions using high T/sub c/(> or =20 K) and stoichiometric (25 +- 1 at. %Ge) Nb/sub 3/Ge films. Good I-V characteristic with large Josephson current I/sub c/ and high gap voltage is obtained when the amorphous-silicon barrier is sputter deposited at low rf voltage and high Ar ...

Josephson weak links from in situ laser-deposited four-layer structures of YBa2Cu3O(7-x)/PrBa2Cu3O(7-x)/YBa2Cu3O(7-x)/Au. These devices show superconductor/-normal-metal/superconductor-like current-voltage characteristics with good areal scaling of both the critical currents I(c) and resistances R(j) with I(c)R(j) of about 3.5 mV. Constant-voltage current steps observed in ...

Intense and coherent terahertz electromagnetic wave (THz-wave) emission from the intrinsic Josephson junctions (IJJs) in single crystalline high-Tc superconductor Bi2Sr2CaCu2O8+? (Bi-2212) was reported in 2007 [L. Ozyuzer et al., Science 318, (2007) 1291.]. In the present work, we demonstrate the relationship between the bias condition and the resonance state by controlling ...

A novel high-Tc superconducting (HTS) buffered step-edge Josephson junction is fabricated. A 250 nm PrBa2Cu3O7 (PBCO) layer was epitaxially grown on a (001) MgO substrate by PLD, which acts as a buffered template for a step-edge. Argon-ion milling was used to obtain a step-edge with a step angle of 25�. The step-edge is analysed in terms of an extended Wu and Chen model (Wu ...

A thin ferromagnetic layer on a bulk equal-spin-pairing triplet superconductor is shown to mediate a Josephson coupling between the spin ? and ? condensates of the superconductor. By deriving analytic expressions for the bound states at the triplet superconductor-ferromagnet interface, we show that this spin Josephson effect ...

The document describes the procedures used at NIST to calibrate dc voltage standards in terms of the NIST volt. Three calibration services are offered by the Electricity Division: Regular Calibration Service (RCS) of client standard cells at NIST; the Volt Transfer Program (VTP) a process to determine the difference between the NIST volt and the volt as maintained by a group of standard cells in a ...

We consider the first order differential equation with a sinusoidal nonlinearity and periodic time dependence, that is, the periodically driven overdamped pendulum. The problem is studied in the case that the explicit time dependence has symmetries common to pure ac-driven systems. The only bifurcation that exists in the system is a degenerate pitchfork bifurcation, which ...

The bifurcations and transitions to chaos in the dc- and ac-current biased Josephson junction are investigated by numerically integrating the Stewart-McCumber model with an interference ''epsilon cosphi'' term. The initial transient method is proposed and successfully applied to construct the model one-dimensional (1D) ...

Superconductor/normal conductor/superconductor (SNS) Josephson junction series arrays are the subject of research for the realization of a Josephson arbitrary waveform synthesizer (JAWS) based on pulse-driven Josephson junctions. Lumped arrays of SNS Josephson junctions are investigated for this application at the ...

An extended Josephson junction can be described as a microwave cavity coupled to a Josephson oscillator. This is formally equivalent to a Fabry-Perot cavity with a freely vibrating mirror, where it has been shown that radiation pressure from photons in the cavity can reduce (increase) the vibrations of the mirror, effectively cooling ...

An extended Josephson junction can be described as a microwave cavity coupled to a Josephson oscillator. This is formally equivalent to a Fabry-Perot cavity with a freely vibrating mirror, where it has been shown that radiation pressure from photons in the cavity can reduce (increase) the vibrations of the mirror, effectively cooling ...

We apply the time-dependent Ginzburg-Landau (TDGL) equations to study small ac currents of frequency ? in superconducting channels narrow on the scale of London penetration depth. We show that TDGL equations have t -dependent and spatially uniform solutions that describe the order parameter with an oscillating part of the double frequency coexisting with an ...

Equations describing the resistive state of a layered superconductor with anisotropic pairing are derived. The similarity with a stack of Josephson junctions is found at small voltages only, when current density in the direction perpendicular to the layers can be interpreted as a sum of the Josephson superconducting, the Ohmic dissipative, and the ...

We discuss how to control dc Josephson current by influencing the structure and nonequilibrium population of Andreev levels via external electrostatic gates, current injection and electromagnetic radiation. In particular we will consider the `giant' Josephson critical current in `long' SIS tunnel junctions and the regular and anomalous nonequilibrium ...

We calculate the angular dependence of the power of stimulated terahertz amplified radiation (STAR) emitted from a dc voltage applied across a stack of intrinsic Josephson junctions. During coherent emission, we assume a spatially uniform ac Josephson current density in the stack acts as a surface electric current density antenna ...

... through submillimeter radiation; B. Conformation of general relativistic effects, equivalent to the red shift, for charged particles, and C. Studies of the ...

The steady-state Josephson effect is studied in superconductor-semiconductor-superconductor junctions (S-Sc-S). The dependence of the critical current on effective mass and charge-carrier density is obtained for arbitrary temperatures.

The value of the Josephson current in an S-M-S system, where M contains low-dimensional electron gas, can be affected noticeably by an applied voltage (field effect). This effect is directly related to the possibility of building a three-terminal device. ...

We analyze theoretically the phenomena related to the Josephson effect for exciton and polariton condensates, taking into account their specific spin degrees of freedom. We distinguish between two types of Josephson effects: the extrinsic effect, related to the coherent tunneling of particles ...

We develop a theory for the Josephson effects in 2-gap intrinsic Josephson junction stacks (IJJ's). The coupled dynamical equations for the phase differences are derived from the low-energy effective Lagrangian. The equations can describe the longitudinal Josephson plasma and the ...

By using a highly sensitive homemade AC magnetic susceptibility technique, the magnetic flux penetration has been measured in YBa2Cu3O7 ? ? single crystals with giant screw dislocations (having the structure of the Archimedean spirals) exhibiting a = 3 spiral turnings, the pitch b = 18.7 ?m and the step height c = 1.2 nm (the last parameter is responsible for creation of ...

A theory of the nonsteady Josephson effect in superconducting contacts of constant voltage V (or V to vary only slightly in time of the order of ..delta../sup -1/) is examined. (AIP)

Significant progress has been made during the past two years in the development of millimeter wave superconducting devices. The present status of bolometric detectors and mixers, Josephson effect mixers, quasiparticle mixers, and Josephson effect parametric amplifiers will be reviewed.

Significant progress has been made during the past two years in the development of millimeter wave superconducting devices. The present status of bolometric detectors and mixers, Josephson-effect mixers, quasiparticle mixers, and Josephson-effect parametric amplifiers will be reviewed.

This paper discusses the observation of quantum effects in the macroscopic system of a Josephson tunnel junction. The macroscopic degree of freedom is the phase difference delta between the phases of the order parameters in the two superconductors on eith...

S>It is shown that first- and second-sound resonance can lead to the appearance of spurious stable states and pumping phenomena in the Richards- Anderson experiment on the Josephson effecet in superfluid helium, and proposals are made for their elimination. (auth)

Coherent microwave-induced effects in 2D arrays of hysteretic Josephson junctions placed in a perpendicular magnetic field are theoretically investigated. Two new phenomena: fractional inverse giant Josephson effect and modification of the V-A characteristic beyond Shapiro steps are found. A theory of these ...

In order to establish a quantum ac voltage standard at NMIJ/AIST, we have developed a Josephson arbitrary waveform synthesizer based on overdamped Josephson junction arrays (JJAs) using optoelectronics and a liquid helium free compact cryocooler. We have succeeded in the generation of sine waves at 60 Hz and 152.6 kHz. To verify the ...

It is shown that a voltage-biased Josephson junction with sufficientlu low dissipation is a macroscopic analog of an atomic system with discrete energy levels. Each of the energy levels is a periodic function of the bias voltage with a period of 2e/C, where C is the intrinsic junction capacitance. Macroscopic spectra can be obtained by measuring the AC ...

This paper reports the phenomena produced in transmission line containing multi-Josephson junctions. The presented model consists of a distributed Josephson line connected by successive inductances and Josephson junctions, and a lossless transmission line. In this paper, a procedure of modeling the multiJosephson ...

... THIN FILMS, *CRYOGENICS, *PROXIMITY DEVICES, METALS, MAGNETIC FIELDS, INTERFACES, MOLYBDENUM, SURFACES, NIOBIUM, ...

The data is reviewed about superconductor-normal-superconductor (SNS) devices, and the conclusion is

Jan 21, 2000... characteristic typical of the Josephson effect. The critical current for the flow was also measured as a function of temperature. ...

... effect relates to a supercurrent flow thru a thin barrier between two superconductors by quantum mechanical tunneling of electron pairs; in other ...

... FLUX(RATE), THIN FILMS, FABRICATION, MOLYBDENUM, MICROWAVES, NIOBIUM, GERMANIUM, CRYOGENICS, FREQUENCY AGILITY ...

... Accession Number : ADD519805. Title : Characterization of Niobium Point Contacts Showing Josephson Effects in the Far Infrared. ...