Science.gov

Sample records for high-capacity optical storage

  1. Promising Rapid Access High-Capacity Mass Storage Technique For Diagnostic Information Utilizing Optical Disc

    NASA Astrophysics Data System (ADS)

    Colby, R. L.; Bartuska, A. J.; Herzog, D. G.

    1982-01-01

    The optical disc has become a new technique for mass digital data storage of X-ray images from examinations and films in todays hospitals. Up to 36,000 X-ray images can be stored on one side of a 12-inch disc by melting holes 0.015 mils in size in an ablative material such as tellerium with a laser beam. This unique characteristic makes the disc suitable for storage and retrieval of X-rays in a record and playback system in either a single disc or multiple disc "jukebox" configuration. Doctors, nurses, technicians and other hospital personnel can call up a particular X-ray in less than 0.6 of a second in an on-line single disc system and up to less than 6 seconds in an on-line "jukebox" system. The jukebox is configured to hold up to 100 discs, thus storing 3,600,000 X-rays in hospitals with a bed size of greater than 500. The estimated exposed films on file in those hospitals is 327,400,000 and the estimated annual X-ray exams are 44,300. Thus, a single disc system could be used for an all electronic X-ray scanning system for annual X-ray exams. The jukebox configuration, which has expansion capability for servicing multiple simultaneous user request, can be applied to large archival mass storage. These systems could store the existing exposed films in hospitals with bed size greater than 500 at record and playback data rates of 50 Mb/s with access times of less than 15 seconds.

  2. Development of high-capacity antimatter storage

    NASA Astrophysics Data System (ADS)

    Howe, Steven D.; Smith, Gerald A.

    2000-01-01

    Space is vast. Over the next few decades, humanity will strive to send probes farther and farther into space to establish long baselines for interferometry, to visit the Kuiper Belt, to identify the heliopause, or to map the Oort cloud. In order to solve many of the mysteries of the universe or to explore the solar system and beyond, one single technology must be developed-high performance propulsion. In essence, future missions to deep space will require specific impulses between 50,000 and 200,000 seconds and energy densities greater than 1014 j/kg in order to accomplish the mission within the career lifetime of an individual, 40 years. Only two technologies available to mankind offer such performance-fusion and antimatter. Currently envisioned fusion systems are too massive. Alternatively, because of the high energy density, antimatter powered systems may be relatively compact. The single key technology that is required to enable the revolutionary concept of antimatter propulsion is safe, reliable, high-density storage. Under a grant from the NASA Institute of Advanced Concepts, we have identified two potential mechanisms that may enable high capacity antimatter storage systems to be built. We will describe planned experiments to verify the concepts. Development of a system capable of storing megajoules per gram will allow highly instrumented platforms to make fast missions to great distances. Such a development will open the universe to humanity. .

  3. High capacity hydrogen storage nanocomposite materials

    DOEpatents

    Zidan, Ragaiy; Wellons, Matthew S

    2015-02-03

    A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

  4. Towards green high capacity optical networks

    NASA Astrophysics Data System (ADS)

    Glesk, I.; Mohd Warip, M. N.; Idris, S. K.; Osadola, T. B.; Andonovic, I.

    2012-02-01

    The demand for fast, secure, energy efficient high capacity networks is growing. It is fuelled by transmission bandwidth needs which will support among other things the rapid penetration of multimedia applications empowering smart consumer electronics and E-businesses. All the above trigger unparallel needs for networking solutions which must offer not only high-speed low-cost "on demand" mobile connectivity but should be ecologically friendly and have low carbon footprint. The first answer to address the bandwidth needs was deployment of fibre optic technologies into transport networks. After this it became quickly obvious that the inferior electronic bandwidth (if compared to optical fiber) will further keep its upper hand on maximum implementable serial data rates. A new solution was found by introducing parallelism into data transport in the form of Wavelength Division Multiplexing (WDM) which has helped dramatically to improve aggregate throughput of optical networks. However with these advancements a new bottleneck has emerged at fibre endpoints where data routers must process the incoming and outgoing traffic. Here, even with the massive and power hungry electronic parallelism routers today (still relying upon bandwidth limiting electronics) do not offer needed processing speeds networks demands. In this paper we will discuss some novel unconventional approaches to address network scalability leading to energy savings via advance optical signal processing. We will also investigate energy savings based on advanced network management through nodes hibernation proposed for Optical IP networks. The hibernation reduces the network overall power consumption by forming virtual network reconfigurations through selective nodes groupings and by links segmentations and partitionings.

  5. Towards green high capacity optical networks

    NASA Astrophysics Data System (ADS)

    Glesk, I.; Mohd Warip, M. N.; Idris, S. K.; Osadola, T. B.; Andonovic, I.

    2011-09-01

    The demand for fast, secure, energy efficient high capacity networks is growing. It is fuelled by transmission bandwidth needs which will support among other things the rapid penetration of multimedia applications empowering smart consumer electronics and E-businesses. All the above trigger unparallel needs for networking solutions which must offer not only high-speed low-cost "on demand" mobile connectivity but should be ecologically friendly and have low carbon footprint. The first answer to address the bandwidth needs was deployment of fibre optic technologies into transport networks. After this it became quickly obvious that the inferior electronic bandwidth (if compared to optical fiber) will further keep its upper hand on maximum implementable serial data rates. A new solution was found by introducing parallelism into data transport in the form of Wavelength Division Multiplexing (WDM) which has helped dramatically to improve aggregate throughput of optical networks. However with these advancements a new bottleneck has emerged at fibre endpoints where data routers must process the incoming and outgoing traffic. Here, even with the massive and power hungry electronic parallelism routers today (still relying upon bandwidth limiting electronics) do not offer needed processing speeds networks demands. In this paper we will discuss some novel unconventional approaches to address network scalability leading to energy savings via advance optical signal processing. We will also investigate energy savings based on advanced network management through nodes hibernation proposed for Optical IP networks. The hibernation reduces the network overall power consumption by forming virtual network reconfigurations through selective nodes groupings and by links segmentations and partitionings.

  6. Robo-line storage: Low latency, high capacity storage systems over geographically distributed networks

    NASA Technical Reports Server (NTRS)

    Katz, Randy H.; Anderson, Thomas E.; Ousterhout, John K.; Patterson, David A.

    1991-01-01

    Rapid advances in high performance computing are making possible more complete and accurate computer-based modeling of complex physical phenomena, such as weather front interactions, dynamics of chemical reactions, numerical aerodynamic analysis of airframes, and ocean-land-atmosphere interactions. Many of these 'grand challenge' applications are as demanding of the underlying storage system, in terms of their capacity and bandwidth requirements, as they are on the computational power of the processor. A global view of the Earth's ocean chlorophyll and land vegetation requires over 2 terabytes of raw satellite image data. In this paper, we describe our planned research program in high capacity, high bandwidth storage systems. The project has four overall goals. First, we will examine new methods for high capacity storage systems, made possible by low cost, small form factor magnetic and optical tape systems. Second, access to the storage system will be low latency and high bandwidth. To achieve this, we must interleave data transfer at all levels of the storage system, including devices, controllers, servers, and communications links. Latency will be reduced by extensive caching throughout the storage hierarchy. Third, we will provide effective management of a storage hierarchy, extending the techniques already developed for the Log Structured File System. Finally, we will construct a protototype high capacity file server, suitable for use on the National Research and Education Network (NREN). Such research must be a Cornerstone of any coherent program in high performance computing and communications.

  7. High Capacity High Speed Optical Data Storage System Based on Diffraction-Free Nanobeam. Final Report, 09-02-98 to 03-17-99

    SciTech Connect

    Tin Aye

    1999-06-16

    Physical Optics Corporation (POC) investigated the development of an optical data storage system built around a current well-engineered high-speed optical disk system with an innovative diffraction-free micro-optical element to produce a beam {approximately}250 nm wide with {approximately}4-5 mm depth of focus, allowing the system to address data at {approximately}100 Mbits/second and to store it 100 to 1,000 times more densely ({approximately}10 Gbit/in.{sup 2}) than in present systems. In Phase 1 of this project POC completed a thorough feasibility study by system design and analysis, successfully demonstrated fabrication of the key components, and conducted a proof-of-principle experimental demonstration. Specifically, production of a subwavelength ({approximately}380 nm) large depth of focus ({approximately}4-5 mm) addressing beam was demonstrated by fabricating a special microdiffractive optical element and recording this beam on a standard optical recording disk coated with a photopolymer material.

  8. Charged fullerenes as high-capacity hydrogen storage media.

    PubMed

    Yoon, Mina; Yang, Shenyuan; Wang, Enge; Zhang, Zhenyu

    2007-09-01

    Using first-principles calculations within density functional theory, we explore systematically the capacity of charged carbon fullerenes Cn (20 storage media. We find that the binding strength of molecular hydrogen on either positively or negatively charged fullerenes can be dramatically enhanced to 0.18-0.32 eV, a desirable range for potential room-temperature, near ambient applications. The enhanced binding is delocalized in nature, surrounding the whole surface of a charged fullerene, and is attributed to the polarization of the hydrogen molecules by the high electric field generated near the surface of the charged fullerene. At full hydrogen coverage, these charged fullerenes can gain storage capacities of up to approximately 8.0 wt %. We also find that, contrary to intuitive expectation, fullerenes containing encapsulated metal atoms only exhibit negligible enhancement in the hydrogen binding strength, because the charge donated by the metal atoms is primarily confined inside the fullerene cages. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage media. PMID:17718530

  9. Charged Fullerenes as High Capacity Hydrogen Storage Media

    SciTech Connect

    Yoon, Mina; Yang, Shenyuan; Wang, Enge; Zhang, Zhenyu

    2007-01-01

    Using first-principles calculations within density functional theory, we explore systematically the capacity of charged carbon fullerenes Cn (20≤n≤84) as hydrogen storage media. We find that the binding strength of molecular hydrogen on either positively or negatively charged fullerenes can be dramatically enhanced to 0.18-0.32 eV, a desirable range for potential room-temperature, near ambient applications. The enhanced binding is delocalized in nature, surrounding the whole surface of a charged fullerene, and is attributed to the polarization of the hydrogen molecules by the high electric field generated near the surface of the charged fullerene. At full hydrogen coverage, these charged fullerenes can gain storage capacities of up to ~8.0wt%. We also find that, contrary to intuitive expectation, fullerenes containing intercalated metal atoms only exhibit negligible enhancement in the hydrogen binding strength, because the charge donated by the metal atoms is primarily confined inside the fullerene cages. These predictions may prove to be instrumental in searching for a new class of high capacity hydrogen storage media.

  10. Design of high-capacity fiber-optic transport systems

    NASA Astrophysics Data System (ADS)

    Liao, Zhi Ming

    2001-08-01

    We study the design of fiber-optic transport systems and the behavior of fiber amplifiers/lasers with the aim of achieving higher capacities with larger amplifier spacing. Solitons are natural candidates for transmitting short pulses for high-capacity fiber-optic networks because of its innate ability to use two of fiber's main defects, fiber dispersion and fiber nonlinearity to balance each other. In order for solitons to retain its dynamic nature, amplifiers must be placed periodically to restore powers to compensate for fiber loss. Variational analysis is used to study the long-term stability of a periodical- amplifier system. A new regime of operation is identified which allows the use of a much longer amplifier spacing. If optical fibers are the blood vessels of an optical communication system, then the optical amplifier based on erbium-doped fiber is the heart. Optical communication systems can avoid the use of costly electrical regenerators to maintain system performance by being able to optically amplify the weakened signals. The length of amplifier spacing is largely determined by the gain excursion experienced by the solitons. We propose, model, and demonstrate a distributed erbium-doped fiber amplifier which can drastically reduce the amount of gain excursion experienced by the solitons, therefore allowing a much longer amplifier spacing and superior stability. Dispersion management techniques have become extremely valuable tools in the design of fiber-optic communication systems. We have studied in depth the advantage of different arnplification schemes (lumped and distributed) for various dispersion compensation techniques. We measure the system performance through the Q factor to evaluate the added advantage of effective noise figure and smaller gain excursion. An erbium-doped fiber laser has been constructed and characterized in an effort to develop a test bed to study transmission systems. The presence of mode-partition noise in an erbium

  11. Metal-diboride nanotubes as high capacity hydrogen storage media

    SciTech Connect

    Meng, Sheng; Kaxiras, Efthimios; Zhang, Zhenyu

    2007-01-01

    We investigate the potential for hydrogen storage of a new class of nanomaterials, metal-diboride nanotubes. These materials have the merits of high density of binding sites on the tubular surfaces without the adverse effects of metal clustering. Using the TiB2 (8,0) and (5,5) nanotube as prototype examples, we show through first-principles calculations that each Ti atom can host two intact H2 units, leading to a retrievable hydrogen storage capacity of 5.5 wt%. Most strikingly, the binding energies fall in the desirable range of 0.2-0.6 eV per H2 molecule, endowing these structures with the potential for room temperature, near ambient pressure applications.

  12. Carbon Honeycomb High Capacity Storage for Gaseous and Liquid Species

    NASA Astrophysics Data System (ADS)

    Krainyukova, Nina V.; Zubarev, Evgeniy N.

    2016-02-01

    We report an exceptionally stable honeycomb carbon allotrope obtained by deposition of vacuum-sublimated graphite. The allotrope structures are derived from our low temperature electron diffraction and electron microscopy data. These structures can be both periodic and random and are built exclusively from s p2 -bonded carbon atoms, and may be considered as three-dimensional graphene. They demonstrate high levels of physical absorption of various gases unattainable in other carbon forms such as fullerites or nanotubes. These honeycomb structures can be used not only for storage of various gases and liquids but also as a matrix for new composites.

  13. Carbon Honeycomb High Capacity Storage for Gaseous and Liquid Species.

    PubMed

    Krainyukova, Nina V; Zubarev, Evgeniy N

    2016-02-01

    We report an exceptionally stable honeycomb carbon allotrope obtained by deposition of vacuum-sublimated graphite. The allotrope structures are derived from our low temperature electron diffraction and electron microscopy data. These structures can be both periodic and random and are built exclusively from sp^{2}-bonded carbon atoms, and may be considered as three-dimensional graphene. They demonstrate high levels of physical absorption of various gases unattainable in other carbon forms such as fullerites or nanotubes. These honeycomb structures can be used not only for storage of various gases and liquids but also as a matrix for new composites. PMID:26894716

  14. High-capacity hydrogen storage medium: Ti doped fullerene

    NASA Astrophysics Data System (ADS)

    Guo, Jun; Liu, Zhiguo; Liu, Suqin; Zhao, Xuehui; Huang, Kelong

    2011-01-01

    Using density functional theory, it is shown that titanium doped heterofullerene has superior property of hydrogen storage. The single titanium atom lies at a double bond position of C60 and bonds to four carbons by Dewar interaction. Each titanium atom binds up to six hydrogen molecules. The first and second hydrogen molecules are dissociated to form carbon hydrides with binding energy of -0.43 eV/H. The other four adsorptions are molecular with binding energy of -0.14 eV/H2. For substitutionally dope C60 with six titanium atoms, the gravimetric density of hydrogen reaches the 7.7 wt % limit necessary for applications in the mobile industry.

  15. The H60Si6C54 heterofullerene as high-capacity hydrogen storage medium

    NASA Astrophysics Data System (ADS)

    Yong, Yongliang; Zhou, Qingxiao; Li, Xiaohong; Lv, Shijie

    2016-07-01

    With the great success in Si atoms doped C60 fullerene and the well-established methods for synthesis of hydrogenated carbon fullerenes, this leads naturally to wonder whether Si-doped fullerenes are possible for special applications such as hydrogen storage. Here by using first-principles calculations, we design a novel high-capacity hydrogen storage material, H60Si6C54 heterofullerene, and confirm its geometric stability. It is found that the H60Si6C54 heterofullerene has a large HOMO-LUMO gap and a high symmetry, indicating it is high chemically stable. Further, our finite temperature simulations indicate that the H60Si6C54 heterofullerene is thermally stable at 300 K. H2 molecules would enter into the cage from the Si-hexagon ring because of lower energy barrier. Through our calculation, a maximum of 21 H2 molecules can be stored inside the H60Si6C54 cage in molecular form, leading to a gravimetric density of 11.11 wt% for 21H2@H60Si6C54 system, which suggests that the hydrogenated Si6C54 heterofullerene could be suitable as a high-capacity hydrogen storage material.

  16. Optical Storage.

    ERIC Educational Resources Information Center

    Vanderstar, John

    1987-01-01

    Classifies and briefly describes several types of optical storage media available today--read-only and write-once analog disks, read-only and write-once digital disks and erasable disks. The appropriateness of CD-ROM (compact disk read-only memory) for use in libraries of developing nations is discussed in terms of users' information needs and…

  17. Free space optical communications for ultra high-capacity PON system

    NASA Astrophysics Data System (ADS)

    Shahpari, Ali; Sousa, Artur N.; Ferreira, Ricardo; Lima, Mário; Teixeira, António

    2014-08-01

    We experimentally demonstrate a set of ultra-high capacity free space passive optical networks (PONs) using quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (16-QAM) Nyquist pulse shaped and orthogonal frequency-division multiplexing (OFDM) modulations. Moreover, these technologies support up to 10 Gb/s services per user and allow a smooth and full integration between fiber and optical wireless access networks.

  18. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis?

    NASA Technical Reports Server (NTRS)

    Halem, M.; Shaffer, F.; Palm, N.; Salmon, E.; Raghavan, S.; Kempster, L.

    1998-01-01

    This technology assessment of long-term high capacity data storage systems identifies an emerging crisis of severe proportions related to preserving important historical data in science, healthcare, manufacturing, finance and other fields. For the last 50 years, the information revolution, which has engulfed all major institutions of modem society, centered itself on data-their collection, storage, retrieval, transmission, analysis and presentation. The transformation of long term historical data records into information concepts, according to Drucker, is the next stage in this revolution towards building the new information based scientific and business foundations. For this to occur, data survivability, reliability and evolvability of long term storage media and systems pose formidable technological challenges. Unlike the Y2K problem, where the clock is ticking and a crisis is set to go off at a specific time, large capacity data storage repositories face a crisis similar to the social security system in that the seriousness of the problem emerges after a decade or two. The essence of the storage crisis is as follows: since it could take a decade to migrate a peta-byte of data to a new media for preservation, and the life expectancy of the storage media itself is only a decade, then it may not be possible to complete the transfer before an irrecoverable data loss occurs. Over the last two decades, a number of anecdotal crises have occurred where vital scientific and business data were lost or would have been lost if not for major expenditures of resources and funds to save this data, much like what is happening today to solve the Y2K problem. A pr-ime example was the joint NASA/NSF/NOAA effort to rescue eight years worth of TOVS/AVHRR data from an obsolete system, which otherwise would have not resulted in the valuable 20-year long satellite record of global warming. Current storage systems solutions to long-term data survivability rest on scalable architectures

  19. Array of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance.

    PubMed

    Chao, Dongliang; Zhu, Changrong; Yang, Peihua; Xia, Xinhui; Liu, Jilei; Wang, Jin; Fan, Xiaofeng; Savilov, Serguei V; Lin, Jianyi; Fan, Hong Jin; Shen, Ze Xiang

    2016-01-01

    Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructures, in which a maximized extrinsic pseudocapacitance contribution is identified and verified by kinetics analysis. The graphene foam supported tin(II) sulfide nanoarray anode delivers a high reversible capacity of ∼1,100 mAh g(-1) at 30 mA g(-1) and ∼420 mAh g(-1) at 30 A g(-1), which even outperforms its lithium-ion storage performance. The surface-dominated redox reaction rendered by our tailored ultrathin tin(II) sulfide nanostructures may also work in other layered materials for high-performance sodium-ion storage. PMID:27358085

  20. Array of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance

    NASA Astrophysics Data System (ADS)

    Chao, Dongliang; Zhu, Changrong; Yang, Peihua; Xia, Xinhui; Liu, Jilei; Wang, Jin; Fan, Xiaofeng; Savilov, Serguei V.; Lin, Jianyi; Fan, Hong Jin; Shen, Ze Xiang

    2016-06-01

    Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructures, in which a maximized extrinsic pseudocapacitance contribution is identified and verified by kinetics analysis. The graphene foam supported tin(II) sulfide nanoarray anode delivers a high reversible capacity of ~1,100 mAh g-1 at 30 mA g-1 and ~420 mAh g-1 at 30 A g-1, which even outperforms its lithium-ion storage performance. The surface-dominated redox reaction rendered by our tailored ultrathin tin(II) sulfide nanostructures may also work in other layered materials for high-performance sodium-ion storage.

  1. Array of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance

    PubMed Central

    Chao, Dongliang; Zhu, Changrong; Yang, Peihua; Xia, Xinhui; Liu, Jilei; Wang, Jin; Fan, Xiaofeng; Savilov, Serguei V.; Lin, Jianyi; Fan, Hong Jin; Shen, Ze Xiang

    2016-01-01

    Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructures, in which a maximized extrinsic pseudocapacitance contribution is identified and verified by kinetics analysis. The graphene foam supported tin(II) sulfide nanoarray anode delivers a high reversible capacity of ∼1,100 mAh g−1 at 30 mA g−1 and ∼420 mAh g−1 at 30 A g−1, which even outperforms its lithium-ion storage performance. The surface-dominated redox reaction rendered by our tailored ultrathin tin(II) sulfide nanostructures may also work in other layered materials for high-performance sodium-ion storage. PMID:27358085

  2. High capacity fiber optic sensor networks using hybrid multiplexing techniques and their applications

    NASA Astrophysics Data System (ADS)

    Sun, Qizhen; Li, Xiaolei; Zhang, Manliang; Liu, Qi; Liu, Hai; Liu, Deming

    2013-12-01

    Fiber optic sensor network is the development trend of fiber senor technologies and industries. In this paper, I will discuss recent research progress on high capacity fiber sensor networks with hybrid multiplexing techniques and their applications in the fields of security monitoring, environment monitoring, Smart eHome, etc. Firstly, I will present the architecture of hybrid multiplexing sensor passive optical network (HSPON), and the key technologies for integrated access and intelligent management of massive fiber sensor units. Two typical hybrid WDM/TDM fiber sensor networks for perimeter intrusion monitor and cultural relics security are introduced. Secondly, we propose the concept of "Microstructure-Optical X Domin Refecltor (M-OXDR)" for fiber sensor network expansion. By fabricating smart micro-structures with the ability of multidimensional encoded and low insertion loss along the fiber, the fiber sensor network of simple structure and huge capacity more than one thousand could be achieved. Assisted by the WDM/TDM and WDM/FDM decoding methods respectively, we built the verification systems for long-haul and real-time temperature sensing. Finally, I will show the high capacity and flexible fiber sensor network with IPv6 protocol based hybrid fiber/wireless access. By developing the fiber optic sensor with embedded IPv6 protocol conversion module and IPv6 router, huge amounts of fiber optic sensor nodes can be uniquely addressed. Meanwhile, various sensing information could be integrated and accessed to the Next Generation Internet.

  3. Dual-Size Silicon Nanocrystal-Embedded SiO(x) Nanocomposite as a High-Capacity Lithium Storage Material.

    PubMed

    Park, Eunjun; Yoo, Hyundong; Lee, Jaewoo; Park, Min-Sik; Kim, Young-Jun; Kim, Hansu

    2015-07-28

    SiOx-based materials attracted a great deal of attention as high-capacity Li(+) storage materials for lithium-ion batteries due to their high reversible capacity and good cycle performance. However, these materials still suffer from low initial Coulombic efficiency as well as high production cost, which are associated with the complicated synthesis process. Here, we propose a dual-size Si nanocrystal-embedded SiOx nanocomposite as a high-capacity Li(+) storage material prepared via cost-effective sol-gel reaction of triethoxysilane with commercially available Si nanoparticles. In the proposed nanocomposite, dual-size Si nanocrystals are incorporated into the amorphous SiOx matrix, providing a high capacity (1914 mAh g(-1)) with a notably improved initial efficiency (73.6%) and stable cycle performance over 100 cycles. The highly robust electrochemical and mechanical properties of the dual-size Si nanocrystal-embedded SiOx nanocomposite presented here are mainly attributed to its peculiar nanoarchitecture. This study represents one of the most promising routes for advancing SiOx-based Li(+) storage materials for practical use. PMID:26132999

  4. Test results for a high capacity cryocooler with internal thermal storage

    NASA Astrophysics Data System (ADS)

    Bertele, Ted; Glaister, Dave; Gully, Wilfred; Hendershott, Paul; Levenduski, Robert; Marquardt, Eric; Wilson, Colin

    2012-06-01

    Ball Aerospace and Redstone Aerospace are developing a space cryocooler for cooling complex optical systems whose loads are intermittent. An example of such a system would be an Earth observation satellite that images for only a fraction of its orbit. If a cooler can store refrigeration during the lull and provide it when the system is active, the cooler can be considerably smaller than one sized to provide the full load continuously. Our cooler provides two stages of refrigeration, a stage of intermittent cooling at 35 K for a focal plane assembly and a stage of continuous cooling at 85 K for the surrounding thermal shields. The cooler provides the intermittent cooling by collecting liquid neon in a unique internal thermal storage tank and forwarding it to the focal plane when the heat loads are high. Our paper presents extensive performance data for neon at 35 K. It carries 2 W at 35 K for 30 minutes plus the 8.5 W of continuous cooling at 85 K for less than 300 W DC power. It is ready to cool again in an hour. For contrast, the same hardware was filled with nitrogen and tested at 82 K. It carries 5 W for 25 minutes plus 15 W of continuous cooling at 130 K for less than 220 W DC power. It is ready to cool again in a little over an hour. The system has many features for space system compatibility. Because the storage is located within an active control loop, the cooler can maintain the 35 K interface temperature to better than ± 0.1 K. Because it circulates liquid it can be located remotely, which solves many compatibility issues. And with careful liquid management, it can work in any orientation and in 0-g. In this paper our flight like equipment will be described, and its continuing evolution to flight will be discussed.

  5. Optical signal processing for enabling high-speed, highly spectrally efficient and high capacity optical systems

    NASA Astrophysics Data System (ADS)

    Fazal, Muhammad Irfan

    The unabated demand for more capacity due to the ever-increasing internet traffic dictates that the boundaries of the state of the art maybe pushed to send more data through the network. Traditionally, this need has been satisfied by multiple wavelengths (wavelength division multiplexing), higher order modulation formats and coherent communication (either individually or combined together). WDM has the ability to reduce cost by using multiple channels within the same physical fiber, and with EDFA amplifiers, the need for O-E-O regenerators is eliminated. Moreover the availability of multiple colors allows for wavelength-based routing and network planning. Higher order modulation formats increases the capacity of the link by their ability to encode data in both the phase and amplitude of light, thereby increasing the bits/sec/Hz as compared to simple on-off keyed format. Coherent communications has also emerged as a primary means of transmitting and receiving optical data due to its support of formats that utilize both phase and amplitude to further increase the spectral efficiency of the optical channel, including quadrature amplitude modulation (QAM) and quadrature phase shift keying (QPSK). Polarization multiplexing of channels can double capacity by allowing two channels to share the same wavelength by propagating on orthogonal polarization axis and is easily supported in coherent systems where the polarization tracking can be performed in the digital domain. Furthermore, the forthcoming IEEE 100 Gbit/s Ethernet Standard, 802.3ba, provides greater bandwidth, higher data rates, and supports a mixture of modulation formats. In particular, Pol-MUX QPSK is increasingly becoming the industry's format of choice as the high spectral efficiency allows for 100 Gbit/s transmission while still occupying the current 50 GHz/channel allocation of current 10 Gbit/s OOK fiber systems. In this manner, 100 Gbit/s transfer speeds using current fiber links, amplifiers, and filters

  6. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis

    NASA Technical Reports Server (NTRS)

    Halem, M.; Shaffer, F.; Palm, N.; Salmon, E.; Raghavan, S.; Kempster, L.

    1998-01-01

    The density of digital storage media in our information-intensive society increases by a factor of four every three years, while the rate at which this data can be migrated to viable long-term storage has been increasing by a factor of only four every nine years. Meanwhile, older data stored on increasingly obsolete media, are at considerable risk. When the systems for which the media were designed are no longer serviced by their manufacturers (many of whom are out of business), the data will no longer be accessible. In some cases, older media suffer from a physical breakdown of components - tapes simply lose their magnetic properties after a long time in storage. The scale of the crisis is compatible to that facing the Social Security System. Greater financial and intellectual resources to the development and refinement of new storage media and migration technologies in order to preserve as much data as possible.

  7. High capacity hydrogen storage materials: attributes for automotive applications and techniques for materials discovery.

    PubMed

    Yang, Jun; Sudik, Andrea; Wolverton, Christopher; Siegel, Donald J

    2010-02-01

    Widespread adoption of hydrogen as a vehicular fuel depends critically upon the ability to store hydrogen on-board at high volumetric and gravimetric densities, as well as on the ability to extract/insert it at sufficiently rapid rates. As current storage methods based on physical means--high-pressure gas or (cryogenic) liquefaction--are unlikely to satisfy targets for performance and cost, a global research effort focusing on the development of chemical means for storing hydrogen in condensed phases has recently emerged. At present, no known material exhibits a combination of properties that would enable high-volume automotive applications. Thus new materials with improved performance, or new approaches to the synthesis and/or processing of existing materials, are highly desirable. In this critical review we provide a practical introduction to the field of hydrogen storage materials research, with an emphasis on (i) the properties necessary for a viable storage material, (ii) the computational and experimental techniques commonly employed in determining these attributes, and (iii) the classes of materials being pursued as candidate storage compounds. Starting from the general requirements of a fuel cell vehicle, we summarize how these requirements translate into desired characteristics for the hydrogen storage material. Key amongst these are: (a) high gravimetric and volumetric hydrogen density, (b) thermodynamics that allow for reversible hydrogen uptake/release under near-ambient conditions, and (c) fast reaction kinetics. To further illustrate these attributes, the four major classes of candidate storage materials--conventional metal hydrides, chemical hydrides, complex hydrides, and sorbent systems--are introduced and their respective performance and prospects for improvement in each of these areas is discussed. Finally, we review the most valuable experimental and computational techniques for determining these attributes, highlighting how an approach that

  8. Towards practical, high-capacity, low-maintenance information storage in synthesized DNA.

    PubMed

    Goldman, Nick; Bertone, Paul; Chen, Siyuan; Dessimoz, Christophe; LeProust, Emily M; Sipos, Botond; Birney, Ewan

    2013-02-01

    Digital production, transmission and storage have revolutionized how we access and use information but have also made archiving an increasingly complex task that requires active, continuing maintenance of digital media. This challenge has focused some interest on DNA as an attractive target for information storage because of its capacity for high-density information encoding, longevity under easily achieved conditions and proven track record as an information bearer. Previous DNA-based information storage approaches have encoded only trivial amounts of information or were not amenable to scaling-up, and used no robust error-correction and lacked examination of their cost-efficiency for large-scale information archival. Here we describe a scalable method that can reliably store more information than has been handled before. We encoded computer files totalling 739 kilobytes of hard-disk storage and with an estimated Shannon information of 5.2 × 10(6) bits into a DNA code, synthesized this DNA, sequenced it and reconstructed the original files with 100% accuracy. Theoretical analysis indicates that our DNA-based storage scheme could be scaled far beyond current global information volumes and offers a realistic technology for large-scale, long-term and infrequently accessed digital archiving. In fact, current trends in technological advances are reducing DNA synthesis costs at a pace that should make our scheme cost-effective for sub-50-year archiving within a decade. PMID:23354052

  9. Carbon Nanofiber/3D Nanoporous Silicon Hybrids as High Capacity Lithium Storage Materials.

    PubMed

    Park, Hyeong-Il; Sohn, Myungbeom; Kim, Dae Sik; Park, Cheolho; Choi, Jeong-Hee; Kim, Hansu

    2016-04-21

    Carbon nanofiber (CNF)/3D nanoporous (3DNP) Si hybrid materials were prepared by chemical etching of melt-spun Si/Al-Cu-Fe alloy nanocomposites, followed by carbonization using a pitch. CNFs were successfully grown on the surface of 3DNP Si particles using residual Fe impurities after acidic etching, which acted as a catalyst for the growth of CNFs. The resulting CNF/3DNP Si hybrid materials showed an enhanced cycle performance up to 100 cycles compared to that of the pristine Si/Al-Cu-Fe alloy nanocomposite as well as that of bare 3DNP Si particles. These results indicate that CNFs and the carbon coating layer have a beneficial effect on the capacity retention characteristics of 3DNP Si particles by providing continuous electron-conduction pathways in the electrode during cycling. The approach presented here provides another way to improve the electrochemical performances of porous Si-based high capacity anode materials for lithium-ion batteries. PMID:26970098

  10. Sc-coated Si@Al12 as high-capacity hydrogen storage medium

    NASA Astrophysics Data System (ADS)

    Lu, Q. L.; Wan, J. G.

    2010-06-01

    Hydrogen molecules adsorption and storage in Sc coated Si@Al12 cluster were investigated using density functional theory methods. Scandium atoms can bind strongly to the surfaces of Si@Al12 due to the charge transfer between Sc and Si@Al12, and do not suffer from clustering on the substrate. Si@Al12 cluster coated with three and four Sc atoms can adsorb 16 and 18 H2 molecules with a binding energy of 0.28-0.63 eV/H2, corresponding to hydrogen storage capacity of 6.0 and 6.3 wt %, respectively. The stable Si@Al12 can be applied as one of candidates for hydrogen storage materials at ambient conditions.

  11. Li and Ca Co-decorated carbon nitride nanostructures as high-capacity hydrogen storage media

    NASA Astrophysics Data System (ADS)

    Wang, Yusheng; Ji, Yong; Li, Meng; Yuan, Pengfei; Sun, Qiang; Jia, Yu

    2011-11-01

    Using first-principles method based on density functional theory, we perform a detailed study of the hydrogen storage properties of Li and Ca co-decorated graphene-like carbon nitride (g-CN) nanostructures. The results show that the average adsorption energy of the molecular hydrogen is ˜0.26 eV/H2, which is acceptable for reversible H2 adsorption/desorption near ambient temperature. Moreover, the findings also show that the storage capacity of the Li and Ca co-decorated g-CN can reach up to 9.17 wt %, presenting a good potential as hydrogen storage material. Regarding the H2 adsorption mechanism, it is demonstrated that the Li adatoms become positively charged through charge transferring to g-CN and then bind hydrogen molecules via the polarization mechanism.

  12. Charge/discharge characteristics of high-capacity methane adsorption storage systems

    SciTech Connect

    Blazek, C.F.; Jasionowski, W.J.; Tiller, A.J. ); Gauthier, S.W. )

    1990-01-01

    The physical and economic barriers restricting a broad acceptance of natural gas as an alternative fuel in the transportation market have proven to be formidable. In order to succeed in the marketplace, systems for storing, dispensing, and utilizing natural gas which are low-cost, lightweight, compact, and efficient must be developed and evaluated. Experiments and numerical modeling indicate that methane storage and delivery are enhanced by low flow rates, high pressures, and designs with low adsorbent-to-cylinder mass ratios. When the adsorbent-to-cylinder mass ratio is greater than 0.3, systems behavior changes from near isothermal to adiabatic. Incorporation and utilization of in-situ thermal energy storage (TES) aids heat management, maintains near isothermal conditions and improves overall performance. TES thermally buffers the charging and discharging of an adsorbent system at or near the phase change temperature of the TES media thereby, enhancing storage and delivery of methane. 1 ref., 7 figs., 3 tabs.

  13. Yttrium-dispersed C60 fullerenes as high-capacity hydrogen storage medium

    NASA Astrophysics Data System (ADS)

    Tian, Zi-Ya; Dong, Shun-Le

    2014-02-01

    Interaction between hydrogen molecules and functionalized C60 is investigated using density functional theory method. Unlike transition metal atoms that tend to cluster on the surface, C60 decorated with 12 Yttrium atoms on each of its 12 pentagons is extremely stable and remarkably enhances the hydrogen adsorption capacity. Four H2 molecules can be chemisorbed on a single Y atom through well-known Dewar-Chatt-Duncanson interaction. The nature of bonding is a weak physisorption for the fifth adsorbed H2 molecule. Consequently, the C60Y12 complex with 60 hydrogen molecules has been demonstrated to lead to a hydrogen storage capacity of ˜6.30 wt. %.

  14. Lithium decoration of three dimensional boron-doped graphene frameworks for high-capacity hydrogen storage

    SciTech Connect

    Wang, Yunhui; Meng, Zhaoshun; Liu, Yuzhen; You, Dongsen; Wu, Kai; Lv, Jinchao; Wang, Xuezheng; Deng, Kaiming; Lu, Ruifeng E-mail: rflu@njust.edu.cn; Rao, Dewei E-mail: rflu@njust.edu.cn

    2015-02-09

    Based on density functional theory and the first principles molecular dynamics simulations, a three-dimensional B-doped graphene-interconnected framework has been constructed that shows good thermal stability even after metal loading. The average binding energy of adsorbed Li atoms on the proposed material (2.64 eV) is considerably larger than the cohesive energy per atom of bulk Li metal (1.60 eV). This value is ideal for atomically dispersed Li doping in experiments. From grand canonical Monte Carlo simulations, high hydrogen storage capacities of 5.9 wt% and 52.6 g/L in the Li-decorated material are attained at 298 K and 100 bars.

  15. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis?

    NASA Technical Reports Server (NTRS)

    Halem, Milton

    1999-01-01

    In a recent address at the California Science Center in Los Angeles, Vice President Al Gore articulated a Digital Earth Vision. That vision spoke to developing a multi-resolution, three-dimensional visual representation of the planet into which we can roam and zoom into vast quantities of embedded geo-referenced data. The vision was not limited to moving through space, but also allowing travel over a time-line, which can be set for days, years, centuries, or even geological epochs. A working group of Federal Agencies, developing a coordinated program to implement the Vice President's vision, developed the definition of the Digital Earth as a visual representation of our planet that enables a person to explore and interact with the vast amounts of natural and cultural geo-referenced information gathered about the Earth. One of the challenges identified by the agencies was whether the technology existed that would be available to permanently store and deliver all the digital data that enterprises might want to save for decades and centuries. Satellite digital data is growing by Moore's Law as is the growth of computer generated data. Similarly, the density of digital storage media in our information-intensive society is also increasing by a factor of four every three years. The technological bottleneck is that the bandwidth for transferring data is only growing at a factor of four every nine years. This implies that the migration of data to viable long-term storage is growing more slowly. The implication is that older data stored on increasingly obsolete media are at considerable risk if they cannot be continuously migrated to media with longer life times. Another problem occurs when the software and hardware systems for which the media were designed are no longer serviced by their manufacturers. Many instances exist where support for these systems are phased out after mergers or even in going out of business. In addition, survivability of older media can suffer from

  16. Yttrium-dispersed C{sub 60} fullerenes as high-capacity hydrogen storage medium

    SciTech Connect

    Tian, Zi-Ya; Dong, Shun-Le

    2014-02-28

    Interaction between hydrogen molecules and functionalized C{sub 60} is investigated using density functional theory method. Unlike transition metal atoms that tend to cluster on the surface, C{sub 60} decorated with 12 Yttrium atoms on each of its 12 pentagons is extremely stable and remarkably enhances the hydrogen adsorption capacity. Four H{sub 2} molecules can be chemisorbed on a single Y atom through well-known Dewar-Chatt-Duncanson interaction. The nature of bonding is a weak physisorption for the fifth adsorbed H{sub 2} molecule. Consequently, the C{sub 60}Y{sub 12} complex with 60 hydrogen molecules has been demonstrated to lead to a hydrogen storage capacity of ∼6.30 wt. %.

  17. Feasibility assessment of optical technologies for reliable high capacity feeder links

    NASA Astrophysics Data System (ADS)

    Witternigg, Norbert; Schönhuber, Michael; Leitgeb, Erich; Plank, Thomas

    2013-08-01

    Space telecom scenarios like data relay satellite and broadband/broadcast service providers require reliable feeder links with high bandwidth/data rate for the communication between ground station and satellite. Free space optical communication (FSOC) is an attractive alternative to microwave links, improving performance by offering abundant bandwidth at small apertures of the optical terminals. At the same time Near-Earth communication by FSOC avoids interference with other services and is free of regulatory issues. The drawback however is the impairment by the laser propagation through the atmosphere at optical wavelengths. Also to be considered are questions of eye safety for ground personnel and aviation. In this paper we assess the user requirements for typical space telecom scenarios and compare these requirements with solutions using optical data links through the atmosphere. We suggest a site diversity scheme with a number of ground stations and a switching scheme using two optical terminals on-board the satellite. Considering the technology trade-offs between four different optical wavelengths we recommend the future use of 1.5 μm laser technology and calculate a link budget for an atmospheric condition of light haze on the optical path. By comparing link budgets we show an outlook to the future potential use of 10 μm laser technology.

  18. Optical information storage in cellular mobile terminals

    NASA Astrophysics Data System (ADS)

    Makela, Jakke S.; Aikio, Janne K.; Vadde, Venkatesh; Kolehmainen, Timo T.; Karioja, Pentti

    2001-11-01

    The trend towards so-called digital convergence (multiple functionality within a single terminal) is opening up a need for high-capacity storage within the cellular mobile terminals (CMT). Solid-state memories and magnetic microdrives are the most commercially mature options. Optical disk technology in this size range is immature, but has a unique potential: no other medium at present has the capability to be simultaneously low-cost, high-capacity, and exchangeable. In this paper, we explore the requirements for the implementation of optical disk storage in a CMT environment. From the technical point of view, these requirements include small form factor, high-enough data density and throughput, low power consumption, robustness, low cost, mass productability, and modularity. Although current technologies may satisfy some of these requirements individually, there is a need for combined optimization of all of these parameters. From the commercial point of view, the most crucial requirement is global standardization. Such standardization is crucial if wide interoperability is wanted (between CMT manufacturers, and even more crucially between CMTs and other appliances). Current optical storage standards are industry-driven and tend to be proprietary and/or incompatible. Even if the technical challenges can be met, optical data storage is not likely to be accepted in CMT applications unless global standardization proceeds more quickly than it is doing at present.

  19. Optically amplified high capacity transmission at 20 Gbit/s by TDM

    NASA Astrophysics Data System (ADS)

    Lee, W. S.; Pettitt, G. A.; Wakefield, J.; Patel, B. L.; Hadjifotiou, A.

    1994-03-01

    Optical transmission at 20 Gbit/s over standard singlemode and dispersion-shifted fiber has been investigated. By exploiting the chirp characteristic of the LiNbO3 modulator, a sensitivity penalty of less than 1 dB has been demonstrated over 20 km of standard fiber. With dispersion compensation, transmission over a single 80 km span of standard fiber was achieved with -32.7 dBm sensitivity. Transmission over 420 km of dispersion-shifted fiber was also demonstrated with an optical sensitivity of -31.1 dBm.

  20. Orbital Angular Momentum-based Space Division Multiplexing for High-capacity Underwater Optical Communications.

    PubMed

    Ren, Yongxiong; Li, Long; Wang, Zhe; Kamali, Seyedeh Mahsa; Arbabi, Ehsan; Arbabi, Amir; Zhao, Zhe; Xie, Guodong; Cao, Yinwen; Ahmed, Nisar; Yan, Yan; Liu, Cong; Willner, Asher J; Ashrafi, Solyman; Tur, Moshe; Faraon, Andrei; Willner, Alan E

    2016-01-01

    To increase system capacity of underwater optical communications, we employ the spatial domain to simultaneously transmit multiple orthogonal spatial beams, each carrying an independent data channel. In this paper, we show up to a 40-Gbit/s link by multiplexing and transmitting four green orbital angular momentum (OAM) beams through a single aperture. Moreover, we investigate the degrading effects of scattering/turbidity, water current, and thermal gradient-induced turbulence, and we find that thermal gradients cause the most distortions and turbidity causes the most loss. We show systems results using two different data generation techniques, one at 1064 nm for 10-Gbit/s/beam and one at 520 nm for 1-Gbit/s/beam; we use both techniques since present data-modulation technologies are faster for infrared (IR) than for green. For the 40-Gbit/s link, data is modulated in the IR, and OAM imprinting is performed in the green using a specially-designed metasurface phase mask. For the 4-Gbit/s link, a green laser diode is directly modulated. Finally, we show that inter-channel crosstalk induced by thermal gradients can be mitigated using multi-channel equalisation processing. PMID:27615808

  1. Holographic Optical Data Storage

    NASA Technical Reports Server (NTRS)

    Timucin, Dogan A.; Downie, John D.; Norvig, Peter (Technical Monitor)

    2000-01-01

    Although the basic idea may be traced back to the earlier X-ray diffraction studies of Sir W. L. Bragg, the holographic method as we know it was invented by D. Gabor in 1948 as a two-step lensless imaging technique to enhance the resolution of electron microscopy, for which he received the 1971 Nobel Prize in physics. The distinctive feature of holography is the recording of the object phase variations that carry the depth information, which is lost in conventional photography where only the intensity (= squared amplitude) distribution of an object is captured. Since all photosensitive media necessarily respond to the intensity incident upon them, an ingenious way had to be found to convert object phase into intensity variations, and Gabor achieved this by introducing a coherent reference wave along with the object wave during exposure. Gabor's in-line recording scheme, however, required the object in question to be largely transmissive, and could provide only marginal image quality due to unwanted terms simultaneously reconstructed along with the desired wavefront. Further handicapped by the lack of a strong coherent light source, optical holography thus seemed fated to remain just another scientific curiosity, until the field was revolutionized in the early 1960s by some major breakthroughs: the proposition and demonstration of the laser principle, the introduction of off-axis holography, and the invention of volume holography. Consequently, the remainder of that decade saw an exponential growth in research on theory, practice, and applications of holography. Today, holography not only boasts a wide variety of scientific and technical applications (e.g., holographic interferometry for strain, vibration, and flow analysis, microscopy and high-resolution imagery, imaging through distorting media, optical interconnects, holographic optical elements, optical neural networks, three-dimensional displays, data storage, etc.), but has become a prominent am advertising

  2. An open, parallel I/O computer as the platform for high-performance, high-capacity mass storage systems

    NASA Technical Reports Server (NTRS)

    Abineri, Adrian; Chen, Y. P.

    1992-01-01

    APTEC Computer Systems is a Portland, Oregon based manufacturer of I/O computers. APTEC's work in the context of high density storage media is on programs requiring real-time data capture with low latency processing and storage requirements. An example of APTEC's work in this area is the Loral/Space Telescope-Data Archival and Distribution System. This is an existing Loral AeroSys designed system, which utilizes an APTEC I/O computer. The key attributes of a system architecture that is suitable for this environment are as follows: (1) data acquisition alternatives; (2) a wide range of supported mass storage devices; (3) data processing options; (4) data availability through standard network connections; and (5) an overall system architecture (hardware and software designed for high bandwidth and low latency). APTEC's approach is outlined in this document.

  3. From Fundamental Understanding To Predicting New Nanomaterials For High Capacity Hydrogen/Methane Storage and Carbon Capture

    SciTech Connect

    Yildirim, Taner

    2015-03-03

    On-board hydrogen/methane storage in fuel cell-powered vehicles is a major component of the national need to achieve energy independence and protect the environment. The main obstacles in hydrogen storage are slow kinetics, poor reversibility and high dehydrogenation temperatures for the chemical hydrides; and very low desorption temperatures/energies for the physisorption materials (MOF’s, porous carbons). Similarly, the current methane storage technologies are mainly based on physisorption in porous materials but the gravimetric and volumetric storage capacities are below the target values. Finally, carbon capture, a critical component of the mitigation of CO2 emissions from industrial plants, also suffers from similar problems. The solid-absorbers such as MOFs are either not stable against real flue-gas conditions and/or do not have large enough CO2 capture capacity to be practical and cost effective. In this project, we addressed these challenges using a unique combination of computational, synthetic and experimental methods. The main scope of our research was to achieve fundamental understanding of the chemical and structural interactions governing the storage and release of hydrogen/methane and carbon capture in a wide spectrum of candidate materials. We studied the effect of scaffolding and doping of the candidate materials on their storage and dynamics properties. We reviewed current progress, challenges and prospect in closely related fields of hydrogen/methane storage and carbon capture.[1-5] For example, for physisorption based storage materials, we show that tap-densities or simply pressing MOFs into pellet forms reduce the uptake capacities by half and therefore packing MOFs is one of the most important challenges going forward. For room temperature hydrogen storage application of MOFs, we argue that MOFs are the most promising scaffold materials for Ammonia-Borane (AB) because of their unique interior active metal-centers for AB binding and well

  4. Ternary MgTiX-alloys: a promising route towards low-temperature, high-capacity, hydrogen-storage materials.

    PubMed

    Vermeulen, Paul; van Thiel, Emile F M J; Notten, Peter H L

    2007-01-01

    In the search for hydrogen-storage materials with a high gravimetric capacity, Mg(y)Ti((1-y)) alloys, which exhibit excellent kinetic properties, form the basis for more advanced compounds. The plateau pressure of the Mg--Ti--H system is very low (approximately 10(-6) bar at room temperature). A way to increase this pressure is by destabilizing the metal hydride. The foremost effect of incorporating an additional element in the binary Mg--Ti system is, therefore, to decrease the stability of the metal hydride. A model to calculate the effect on the thermodynamic stability of alloying metals was developed by Miedema and co-workers. Adopting this model offers the possibility to select promising elements beforehand. Thin films consisting of Mg and Ti with Al or Si were prepared by means of e-beam deposition. The electrochemical galvanostatic intermittent titration technique was used to obtain pressure-composition isotherms for these ternary materials and these isotherms reveal a reversible hydrogen-storage capacity of more than 6 wt. %. In line with the calculations, substitution of Mg and Ti by Al or Si indeed shifts the plateau pressure of a significant part of the isotherms to higher pressures, while remaining at room temperature. It has been proven that, by controlling the chemistry of the metal alloy, the thermodynamic properties of Mg-based hydrides can be regulated over a wide range. Hence, the possibility to increase the partial hydrogen pressure, while maintaining a high gravimetric capacity creates promising opportunities in the field of hydrogen-storage materials, which are essential for the future of the hydrogen economy. PMID:17879246

  5. Synergistic Na-storage reactions in Sn4P3 as a high-capacity, cycle-stable anode of Na-ion batteries.

    PubMed

    Qian, Jiangfeng; Xiong, Ya; Cao, Yuliang; Ai, Xinping; Yang, Hanxi

    2014-01-01

    Room-temperature Na-ion batteries have attracted great interest as a low cost and environmentally benign technology for large scale electric energy storage, however their development is hindered by the lack of suitable anodic host materials. In this paper, we described a green approach for the synthesis of Sn4P3/C nanocomposite and demonstrated its excellent Na-storage performance as a novel anode of Na-ion batteries. This Sn4P3/C anode can deliver a very high reversible capacity of 850 mA h g(-1) with a remarkable rate capability with 50% capacity output at 500 mA g(-1) and can also be cycled with 86% capacity retention over 150 cycles due to a synergistic Na-storage mechanism in the Sn4P3 anode, where the Sn nanoparticles act as electronic channels to enable electrochemical activation of the P component, while the elemental P and its sodiated product Na3P serve as a host matrix to alleviate the aggregation of the Sn particles during Na insertion reaction. This mechanism may offer a new approach to create high capacity and cycle-stable alloy anodes for Na-ion batteries and other electrochemical energy storage applications. PMID:24611662

  6. Calcium as a superior coating metal in functionalization of carbon fullerenes for high-capacity hydrogen storage

    SciTech Connect

    Yoon, Mina; Yang, Shenyuan; Hicke, Christian; Wang, Enge; Geohegan, David B; Zhang, Zhenyu

    2008-01-01

    We explore theoretically the feasibility of functionalizing carbon nanostructures for hydrogen storage, focusing on the coating of C60 fullerenes with light alkaline-earth metals. Our first-principles density functional theory studies show that both Ca and Sr can bind strongly to the C60 surface, and highly prefer monolayer coating, thereby explaining existing experimental observations. The strong binding is attributed to an intriguing charge transfer mechanism involving the empty d levels of the metal elements. The charge redistribution, in turn, gives rise to electric fields surrounding the coated fullerenes, which can now function as ideal attractors upon molecular hydrogen adsorption with binding strengths strong enough for potential room temperature applications but weak enough to avoid H2 dissociation. With a hydrogen uptake of >8.4wt% on Ca32C60, Ca is superior to all the recently suggested metal coating elements.

  7. Ab initio Design of Ca-Decorated Organic Frameworks for High Capacity Molecular Hydrogen Storage with Enhanced Binding

    SciTech Connect

    Sun, Y. Y.; Lee, K.; Kim, Y. H.; Zhang, S. B.

    2009-01-01

    Ab initio calculations show that Ca can decorate organic linkers of metal-organic framework, MOF-5, with a binding energy of 1.25 eV. The Ca-decorated MOF-5 can store molecular hydrogen (H{sub 2}) in both high gravimetric (4.6 wt %) and high volumetric (36 g/l) capacities. Even higher capacities (5.7 wt % and 45 g/l) can be obtained in a rationally designed covalent organic framework system, COF-{alpha}, with decorated Ca. Both density functional theory and second-order Moller-Plesset perturbation calculations show that the H{sub 2} binding in these systems is significantly stronger than the van der Waals interactions, which is required for H{sub 2} storage at near ambient conditions.

  8. Air-stable magnesium nanocomposites provide rapid and high-capacity hydrogen storage without using heavy-metal catalysts.

    PubMed

    Jeon, Ki-Joon; Moon, Hoi Ri; Ruminski, Anne M; Jiang, Bin; Kisielowski, Christian; Bardhan, Rizia; Urban, Jeffrey J

    2011-04-01

    Hydrogen is a promising alternative energy carrier that can potentially facilitate the transition from fossil fuels to sources of clean energy because of its prominent advantages such as high energy density (142 MJ kg(-1); ref. 1), great variety of potential sources (for example water, biomass, organic matter), light weight, and low environmental impact (water is the sole combustion product). However, there remains a challenge to produce a material capable of simultaneously optimizing two conflicting criteria--absorbing hydrogen strongly enough to form a stable thermodynamic state, but weakly enough to release it on-demand with a small temperature rise. Many materials under development, including metal-organic frameworks, nanoporous polymers, and other carbon-based materials, physisorb only a small amount of hydrogen (typically 1-2 wt%) at room temperature. Metal hydrides were traditionally thought to be unsuitable materials because of their high bond formation enthalpies (for example MgH(2) has a ΔHf~75 kJ mol(-1)), thus requiring unacceptably high release temperatures resulting in low energy efficiency. However, recent theoretical calculations and metal-catalysed thin-film studies have shown that microstructuring of these materials can enhance the kinetics by decreasing diffusion path lengths for hydrogen and decreasing the required thickness of the poorly permeable hydride layer that forms during absorption. Here, we report the synthesis of an air-stable composite material that consists of metallic Mg nanocrystals (NCs) in a gas-barrier polymer matrix that enables both the storage of a high density of hydrogen (up to 6 wt% of Mg, 4 wt% for the composite) and rapid kinetics (loading in <30 min at 200 °C). Moreover, nanostructuring of the Mg provides rapid storage kinetics without using expensive heavy-metal catalysts. PMID:21399630

  9. Dual hybrid strategy towards achieving high capacity and long-life lithium storage of ZnO

    NASA Astrophysics Data System (ADS)

    Xiao, Ying; Cao, Minhua

    2016-02-01

    In this work, we propose a facile and efficient strategy for mitigating capacity fading of ZnO by co-hybridization of cobalt (Co) and N-doped carbon (C-N). The ZnO-based hybrid (ZnO/Co/C-N) is prepared by calcining metal-organic frameworks (MOFs) under a vacuum condition. In view of the unique microstructure of MOFs used in our case, the resultant hybrid displays a three dimensional (3D) spherical morphology with abundant pore structure. The electrochemical tests indicate that the ZnO/Co/C-N nanospheres exhibit excellent cycling stability, high specific capacity, and good rate capability. This work proposes a facile strategy for the synthesis of nanomaterials with unique microstructure, desired composition and high surface area, endowing an excellent lithium storage performance. The current route is convenient and cost-effective, and therefore it is highly promising for scaled-up production. Moreover, the method we adopted may be extended to synthesize other porous nanomaterials with desired composition.

  10. Optical Disks Compete with Videotape and Magnetic Storage Media: Part II.

    ERIC Educational Resources Information Center

    Urrows, Henry; Urrows, Elizabeth

    1988-01-01

    Describes capabilities of Digi-Data's high-capacity computer storage tape drive, Gigastore, and FileTek's Storage Machine/1. Optical digital disk (ODD) leaders' reactions, opinions, and new products are reported. A directory of 13 ODD sources is included. (MES)

  11. Diffractive optical element for optical data storage

    NASA Astrophysics Data System (ADS)

    Yoshida, S.; Unno, N.; Akamatsu, H.; Yamada, K.; Taniguchi, J.; Yamamoto, M.

    2013-05-01

    The diffractive optical element (DOE) has the transformation function of wavefront, and its applications are forming or homogenization of beam, and aberration correction, and so on. In this study, we evaluate possibility as storage application of the DOE. The optical data storage using the DOE is thought of as a kind of holographic data storage (HDS). In the HDS, digital data is recorded and read out as modulated 2-dimensional page data, instead of bit-by-bit recording in conventional optical storages. Therefore, HDS actualize high data transfer rate. We design and optimize phase distribution of the DOE using the iterative method with regularization. In the optimization process, we use iterative Fourier transform algorithm (IFTA) that is known as Gerchberg-Saxton (GS) algorithm. At this time, the regularization method is adopted to suppress minute oscillation of the diffraction pattern. Designed and optimized DOE is fabricated by ultraviolet (UV) nanoimprinting technology. High productivity can be expected by adopting nanoimprinting technology. DOEs are duplicated on the silicon (Si) substrate as reflection-type elements. Fabricated DOE is evaluated in the experiment. We verify that DOE for optical data storage can be actualized through our approach.

  12. High capacity multicomponent hydrogen storage materials: Investigation of the effect of stoichiometry and decomposition conditions on the cycling behaviour of LiBH 4-MgH 2

    NASA Astrophysics Data System (ADS)

    Walker, Gavin S.; Grant, David M.; Price, Tobias C.; Yu, Xuebin; Legrand, Vincent

    LiBH 4-MgH 2 is an attractive reversible hydrogen storage system, it combines two high capacity hydrides (18.3 and 7.6 wt.%, respectively) and the concerted dehydrogenation reaction has a smaller enthalpy change than either species on its own. The latter effect leads to a destabilisation of the hydrided products and results in a lowering of the dehydrogenation temperature. In situ neutron diffraction experiments have been undertaken to characterise the mechanism of decomposition of the LiBD 4-MgD 2 system, with an emphasis on investigating the synergistic effects of the components during cycling under various conditions. This study compares the effect of stoichiometry of the multicomponent system on the cycling mechanism. Results show that LiBD 4-MgD 2 in a 2:1 molar ratio can be reversibly dehydrogenated under low pressures of hydrogen or under vacuum, contrary to earlier reports in the literature, although the reaction was only partially reversed for the 2:1 mixture decomposed under vacuum. This work shows that the reaction pathway was affected by dehydrogenation conditions, but the stoichiometry of the multicomponent system played a minor role.

  13. Optical storage device

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.

    1991-01-01

    A new holographic image storage device which uses four-wave mixing in two photorefractive crystals is described. Photorefractive crystals promise information storage densities on the order of 10(exp 9) to 10(exp 12) bits per cubic centimeter at real-time rates. Several studies in recent years have investigated the use of photorefractive crystals for storing holographic image information. However, all of the previous studies have focused on techniques for storing information in a single crystal. The disadvantage of using a single crystal is that the read process is destructive. Researchers have developed techniques for fixing the information in a crystal so that it may be read many times. However, when fixed, the information cannot be readily erased and overwritten with new information. It two photorefractive crystals are used, holographic image information may be stored dynamically. That is, the stored image information may be read out more than once, and it may be easily erased and overwritten with new image information.

  14. Optical Storage Performance Modeling and Evaluation.

    ERIC Educational Resources Information Center

    Behera, Bailochan; Singh, Harpreet

    1990-01-01

    Evaluates different types of storage media for long-term archival storage of large amounts of data. Existing storage media are reviewed, including optical disks, optical tape, magnetic storage, and microfilm; three models are proposed based on document storage requirements; performance analysis is considered; and cost effectiveness is discussed.…

  15. PLZT optical information storage devices

    SciTech Connect

    Land, C.E.; Schwartz, R.W.; Butler, M.A.; Martin, S.J.

    1990-01-01

    The application of ferroelectric thin films to optical information storage devices depends first on their capability to store optical information, i.e., their intrinsic and/or extrinsic photosensitivities, and then upon some means of detecting and reading the stored optical information with a reasonable signal-to-noise ratio. Based on the method of reading the stored information, the latter capability depends either on the magnitude of the longitudinal electrooptic coefficients or the photocurrent generation efficiency of the films. This paper briefly discusses PZT and PLZT thin film longitudinal electrooptic effects, photosensitivities and photocurrent generation characteristics and some proposed optical information storage devices which will use these properties. 18 refs., 5 figs., 1 tab.

  16. Advanced optical disk storage technology

    NASA Technical Reports Server (NTRS)

    Haritatos, Fred N.

    1996-01-01

    There is a growing need within the Air Force for more and better data storage solutions. Rome Laboratory, the Air Force's Center of Excellence for C3I technology, has sponsored the development of a number of operational prototypes to deal with this growing problem. This paper will briefly summarize the various prototype developments with examples of full mil-spec and best commercial practice. These prototypes have successfully operated under severe space, airborne and tactical field environments. From a technical perspective these prototypes have included rewritable optical media ranging from a 5.25-inch diameter format up to the 14-inch diameter disk format. Implementations include an airborne sensor recorder, a deployable optical jukebox and a parallel array of optical disk drives. They include stand-alone peripheral devices to centralized, hierarchical storage management systems for distributed data processing applications.

  17. ICI optical data storage tape

    NASA Technical Reports Server (NTRS)

    Mclean, Robert A.; Duffy, Joseph F.

    1992-01-01

    Optical data storage tape is now a commercial reality. The world's first successful development of a digital optical tape system is complete. This is based on the Creo 1003 optical tape recorder with ICI 1012 write-once optical tape media. Flexible optical media offers many benefits in terms of manufacture; for a given capital investment, continuous, web-coating techniques produce more square meters of media than batch coating. The coated layers consist of a backcoat on the non-active side; on the active side there is a subbing layer, then reflector, dye/polymer, and transparent protective overcoat. All these layers have been tailored for ease of manufacture and specific functional characteristics.

  18. Optical Storage Developments--Write-Once Media.

    ERIC Educational Resources Information Center

    Edwards, Ian C.

    1987-01-01

    Discusses the user benefits of write-once optical storage devices; describes typical applications in archival storage, one-off complex instruction sets, and information storage and retrieval systems; and identifies current trends toward standardization of equipment. (CLB)

  19. Optical storage in quantized media

    NASA Astrophysics Data System (ADS)

    Djotyan, G. P.; Sandor, N.; Bakos, J. S.; Sörlei, Zs.

    2011-07-01

    The schemes of storing of images in quantum states of atoms being used nowadays are based on electromagnetically induced transparency. The images are stored in the collective atomic coherence with the storage time limited by different relaxation processes in the system with the transverse relaxation being the most detrimental among them. In this communication, we present a method of coherent writing of optical information (a transverse image) into the populations instead of the coherences of the metastable atomic states. The method is based on an action of a sequence of frequency chirped laser pulses on an atom with lambda-structure of working levels. Such storage results in drastic increase of the storage time. The reading out of the stored information is performed by measuring the population of one of the metastable atomic states.

  20. Review of Optical Data Storage

    NASA Astrophysics Data System (ADS)

    Day, Daniel; Gu, Min; Smallridge, Andrew

    As the computer industry grows, so will the requirements for data storage. Magnetic memory has been the most stable method in terms of capacity and recording/reading speed. However, we have reached the point where a substantial increase in the capacity cannot be produced without increasing the size of the system. When compact discs (CDs) were introduced in the 1980s they revolutionized the concept of data storage. Since their inception, the capacity requirements have far exceeded what is available on a compact disc, and they are now following the same path as magnetic memories. Following this trend, it could be assumed that digital versatile discs or digital video discs (DVDs) have a limited lifetime as a storage medium. In fact it has been noted that the maximum capacity of DVDs will be reached in 3-5 years. The question then is what comes next. This chapter aims to illustrate the technology involved in current optical storage methods as well as to introduce several new concepts of optical storage. It is envisaged that a storage system based on either solid immersion lens, holography or three-dimensional bit recording could be the way of the future.The development of optical technology has revolutionized the way we communicate between people or between computers. As society continues to require better tools to communicate more data at higher rates, so does it require the ability to store larger amounts of information. Since the invention of the first computer there has always existed the need for some form of information storage system other than printed hardcopies. One of the first of such systems was computer ribbon; although somewhat awkward it freed the user from having to input the required information at the beginning of every session. At the time this was one of the greatest advances in computer technology. Several other data storage systems have followed over the years, and each time there has been a limit to the amount of information that could be stored.

  1. Optical system storage design with diffractive optical elements

    NASA Technical Reports Server (NTRS)

    Kostuk, Raymond K.; Haggans, Charles W.

    1993-01-01

    Optical data storage systems are gaining widespread acceptance due to their high areal density and the ability to remove the high capacity hard disk from the system. In magneto-optical read-write systems, a small rotation of the polarization state in the return signal from the MO media is the signal which must be sensed. A typical arrangement used for detecting these signals and correcting for errors in tracking and focusing on the disk is illustrated. The components required to achieve these functions are listed. The assembly and alignment of this complex system has a direct impact on cost, and also affects the size, weight, and corresponding data access rates. As a result, integrating these optical components and improving packaging techniques is an active area of research and development. Most designs of binary optic elements have been concerned with optimizing grating efficiency. However, rigorous coupled wave models for vector field diffraction from grating surfaces can be extended to determine the phase and polarization state of the diffracted field, and the design of polarization components. A typical grating geometry and the phase and polarization angles associated with the incident and diffracted fields are shown. In our current stage of work, we are examining system configurations which cascade several polarization functions on a single substrate. In this design, the beam returning from the MO disk illuminates a cascaded grating element which first couples light into the substrate, then introduces a quarter wave retardation, then a polarization rotation, and finally separates s- and p-polarized fields through a polarization beam splitter. The input coupler and polarization beam splitter are formed in volume gratings, and the two intermediate elements are zero-order elements.

  2. CSTI High Capacity Power

    NASA Technical Reports Server (NTRS)

    Winter, Jerry M.

    1989-01-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY-86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY-88, the Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

  3. CSTI high capacity power

    SciTech Connect

    Winter, J.M.

    1994-09-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase I of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY88, the Advanced Technology Program was incorporated into NASA`s new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

  4. Laser beam modeling in optical storage systems

    NASA Technical Reports Server (NTRS)

    Treptau, J. P.; Milster, T. D.; Flagello, D. G.

    1991-01-01

    A computer model has been developed that simulates light propagating through an optical data storage system. A model of a laser beam that originates at a laser diode, propagates through an optical system, interacts with a optical disk, reflects back from the optical disk into the system, and propagates to data and servo detectors is discussed.

  5. High capacity oil burner

    SciTech Connect

    Pedrosa, O.A. Jr.; Couto, N.C.; Fanqueiro, R.C.C.

    1983-11-01

    The present invention relates to a high capacity oil burner comprising a cylindrical atomizer completely surrounded by a protective cylindrical housing having a diameter from 2 to 3 times greater than the diameter of said atomizer; liquid fuels being injected under pressure into said atomizer and accumulating within said atomizer in a chamber for the accumulation of liquid fuels, and compressed air being injected into a chamber for the accumulation of air; cylindrical holes communicating said chamber for the accumulation of liquid fuels with the outside and cylindrical holes communicating said chamber for the accumulation of air with said cylindrical holes communicating the chamber for the accumulation of liquids with the outside so that the injection of compressed air into said liquid fuel discharge holes atomizes said fuel which is expelled to the outside through the end portions of said discharge holes which are circumferentially positioned to be burnt by a pilot flame; said protecting cylindrical housing having at its ends perforated circular rings into which water is injected under pressure to form a protecting fan-like water curtain at the rear end of the housing and a fan-like water curtain at the flame to reduce the formation of soot; the burning efficiency of said burner being superior to 30 barrels of liquid fuel per day/kg of the apparatus.

  6. Use Of A Digital Optical Storage System

    NASA Astrophysics Data System (ADS)

    Collins, M. W.

    1983-01-01

    The Common File System (CFS) is a file management and file storage system for the Los Alamos National Laboratory's computer network. The CFS is organized as a hierarchical storage system: active files are stored on fast-access storage devices, larger, less active files are stored on slower, less expensive devices, and archival files are stored offline. Files are automatically moved between the various classes of storage by a file migration program that analyzes file activity, file size, and storage device capabilities. This has resulted in a cost-effective system that provides both fast access and large data storage capability (over 9 trillion bits currently stored). A large capacity (1014 bits), reliable Digital Optical Storage System would replace the offline storage as the archival part of the CFS and might also be used for active storage if it had a reasonable file access time.

  7. ICI optical data storage tape: An archival mass storage media

    NASA Technical Reports Server (NTRS)

    Ruddick, Andrew J.

    1993-01-01

    At the 1991 Conference on Mass Storage Systems and Technologies, ICI Imagedata presented a paper which introduced ICI Optical Data Storage Tape. This paper placed specific emphasis on the media characteristics and initial data was presented which illustrated the archival stability of the media. More exhaustive analysis that was carried out on the chemical stability of the media is covered. Equally important, it also addresses archive management issues associated with, for example, the benefits of reduced rewind requirements to accommodate tape relaxation effects that result from careful tribology control in ICI Optical Tape media. ICI Optical Tape media was designed to meet the most demanding requirements of archival mass storage. It is envisaged that the volumetric data capacity, long term stability and low maintenance characteristics demonstrated will have major benefits in increasing reliability and reducing the costs associated with archival storage of large data volumes.

  8. 3D intra-stacked CoO/carbon nanocomposites welded by Ag nanoparticles for high-capacity, reversible lithium storage.

    PubMed

    Chae, Changju; Kim, Ki Woong; Kim, Sue Jin; Lee, Daehee; Jo, Yejin; Yun, Young Jun; Moon, Jooho; Choi, Youngmin; Lee, Sun Sook; Choi, Sungho; Jeong, Sunho

    2015-06-21

    A wet-chemical, facile strategy is proposed for forming three-dimensional intra-structured nanocomposites to facilitate the development of high performance anodes for lithium ion batteries. The nanocomposites are composed of cobalt oxide nanoparticles, reduced graphene oxides, and Ag nanoparticles, and all the constituent materials are incorporated homogenously in a layer-by-layer structured geometry by a simple sono-chemical hybridizing process in a single, one-pot batch. Herein, it is revealed that the homogenously intra-stacked oxide, carbon, and metallic phases play critical roles in determining electrochemical performance (i.e. high capacity, rate capability, and cycling stability) of nanocomposite-based anodes, owing to the characteristic chemical/physical nature of constituent materials welded by partial melting of the metallic nanoparticles. In particular, by virtue of a characteristic role of a nano-Ag phase in suppressing the irreversible capacity, a critical drawback for metal oxide-based anodes, excellent capacities are demonstrated (983 and 770 mA h g(-1) at current densities of 100 and 2000 mA g(-1), respectively). PMID:25928095

  9. A System Architect's View Of Optical Storage

    NASA Astrophysics Data System (ADS)

    McIntosh, John W.; Harness, Kent; Parham, Frederick

    1983-11-01

    The design and the development of optical storage creates a significant impact on system architecture. Some of the highlights of optical storage include the following: both direct and sequential access are supported, large units of data are divided into bands that act as the unit of physical and logical data addressahility, and the user deals with logical records that can be of variable length, up to two megabytes. Ease of use is enhanced by the simplicity of data manipulation and access. Future consideratons will allow rapid retrieval of a platter from a library for subsequent automatic insertion of the cartridge into an optical storage unit.

  10. 3D intra-stacked CoO/carbon nanocomposites welded by Ag nanoparticles for high-capacity, reversible lithium storage

    NASA Astrophysics Data System (ADS)

    Chae, Changju; Kim, Ki Woong; Kim, Sue Jin; Lee, Daehee; Jo, Yejin; Yun, Young Jun; Moon, Jooho; Choi, Youngmin; Lee, Sun Sook; Choi, Sungho; Jeong, Sunho

    2015-06-01

    A wet-chemical, facile strategy is proposed for forming three-dimensional intra-structured nanocomposites to facilitate the development of high performance anodes for lithium ion batteries. The nanocomposites are composed of cobalt oxide nanoparticles, reduced graphene oxides, and Ag nanoparticles, and all the constituent materials are incorporated homogenously in a layer-by-layer structured geometry by a simple sono-chemical hybridizing process in a single, one-pot batch. Herein, it is revealed that the homogenously intra-stacked oxide, carbon, and metallic phases play critical roles in determining electrochemical performance (i.e. high capacity, rate capability, and cycling stability) of nanocomposite-based anodes, owing to the characteristic chemical/physical nature of constituent materials welded by partial melting of the metallic nanoparticles. In particular, by virtue of a characteristic role of a nano-Ag phase in suppressing the irreversible capacity, a critical drawback for metal oxide-based anodes, excellent capacities are demonstrated (983 and 770 mA h g-1 at current densities of 100 and 2000 mA g-1, respectively).A wet-chemical, facile strategy is proposed for forming three-dimensional intra-structured nanocomposites to facilitate the development of high performance anodes for lithium ion batteries. The nanocomposites are composed of cobalt oxide nanoparticles, reduced graphene oxides, and Ag nanoparticles, and all the constituent materials are incorporated homogenously in a layer-by-layer structured geometry by a simple sono-chemical hybridizing process in a single, one-pot batch. Herein, it is revealed that the homogenously intra-stacked oxide, carbon, and metallic phases play critical roles in determining electrochemical performance (i.e. high capacity, rate capability, and cycling stability) of nanocomposite-based anodes, owing to the characteristic chemical/physical nature of constituent materials welded by partial melting of the metallic

  11. Diffused holographic information storage and retrieval using photorefractive optical materials

    NASA Astrophysics Data System (ADS)

    McMillen, Deanna Kay

    Holography offers a tremendous opportunity for dense information storage, theoretically one bit per cubic wavelength of material volume, with rapid retrieval, of up to thousands of pages of information simultaneously. However, many factors prevent the theoretical storage limit from being reached, including dynamic range problems and imperfections in recording materials. This research explores new ways of moving closer to practical holographic information storage and retrieval by altering the recording materials, in this case, photorefractive crystals, and by increasing the current storage capacity while improving the information retrieved. As an experimental example of the techniques developed, the information retrieved is the correlation peak from an optical recognition architecture, but the materials and methods developed are applicable to many other holographic information storage systems. Optical correlators can potentially solve any signal or image recognition problem. Military surveillance, fingerprint identification for law enforcement or employee identification, and video games are but a few examples of applications. A major obstacle keeping optical correlators from being universally accepted is the lack of a high quality, thick (high capacity) holographic recording material that operates with red or infrared wavelengths which are available from inexpensive diode lasers. This research addresses the problems from two positions: find a better material for use with diode lasers, and reduce the requirements placed on the material while maintaining an efficient and effective system. This research found that the solutions are new dopants introduced into photorefractive lithium niobate to improve wavelength sensitivities and the use of a novel inexpensive diffuser that reduces the dynamic range and optical element quality requirements (which reduces the cost) while improving performance. A uniquely doped set of 12 lithium niobate crystals was specified and

  12. ``H2 sponge'': pressure as a means for reversible high-capacity hydrogen storage in nanoporous Ca-intercalated covalent organic frameworks

    NASA Astrophysics Data System (ADS)

    Gao, Fei; Sun, Jia Tao; Meng, Sheng

    2015-03-01

    We explore the potential and advantages of Ca-intercalated covalent organic framework-1 (CaCOF-1) as a 3-dimensional (3D) layered material for reversible hydrogen storage. Density functional theory calculations show that by varying the interlayer distance of CaCOF-1, a series of metastable structures can be achieved with the interlayer distance falling in the range of 4.3-4.8 Å. When four hydrogen molecules are adsorbed on each Ca, a high hydrogen uptake of 4.54 wt% can be produced, with the binding energy falling in the ideal range of 0.2-0.6 eV per H2. While H2 absorption is a spontaneous process under H2 rich conditions, tuning the interlayer distance by reasonable external pressure could compress CaCOF-1 to release all of the hydrogen molecules and restore the material to its original state for recyclable use. This provides a new method for gradual, controllable extraction of hydrogen molecules in covalent organic frameworks, satisfying the practical demand for reversible hydrogen storage at ambient temperatures.We explore the potential and advantages of Ca-intercalated covalent organic framework-1 (CaCOF-1) as a 3-dimensional (3D) layered material for reversible hydrogen storage. Density functional theory calculations show that by varying the interlayer distance of CaCOF-1, a series of metastable structures can be achieved with the interlayer distance falling in the range of 4.3-4.8 Å. When four hydrogen molecules are adsorbed on each Ca, a high hydrogen uptake of 4.54 wt% can be produced, with the binding energy falling in the ideal range of 0.2-0.6 eV per H2. While H2 absorption is a spontaneous process under H2 rich conditions, tuning the interlayer distance by reasonable external pressure could compress CaCOF-1 to release all of the hydrogen molecules and restore the material to its original state for recyclable use. This provides a new method for gradual, controllable extraction of hydrogen molecules in covalent organic frameworks, satisfying the

  13. Photorefractive materials for optical storage and display

    NASA Technical Reports Server (NTRS)

    Shah, R. R.; Kim, D. M.; Rabson, T. A.; Tittel, F. K.

    1976-01-01

    Real-time data storage and processing using optical techniques have been considered in recent years. Of particular interest are photosensitive electro-optic crystals which permit volume storage in the form of phase holograms, by means of a charge transfer process. A survey of the state of the art of such holographic memories is presented. The physical mechanism responsible for the formation of phase holograms in such crystals is discussed. Attention is focused on various aspects of materials characterization, development and utilization. Experimental reversible holographic read-write memory systems with fast random access and high storage capacity employing this new class of photosensitive materials have already been demonstrated.

  14. Optical data storage and metallization of polymers

    NASA Technical Reports Server (NTRS)

    Roland, C. M.; Sonnenschein, M. F.

    1991-01-01

    The utilization of polymers as media for optical data storage offers many potential benefits and consequently has been widely explored. New developments in thermal imaging are described, wherein high resolution lithography is accomplished without thermal smearing. The emphasis was on the use of poly(ethylene terephthalate) film, which simultaneously serves as both the substrate and the data storage medium. Both physical and chemical changes can be induced by the application of heat and, thereby, serve as a mechanism for high resolution optical data storage in polymers. The extension of the technique to obtain high resolution selective metallization of poly(ethylene terephthalate) is also described.

  15. Optical Discs: New Storage Media for Education.

    ERIC Educational Resources Information Center

    Helgerson, Linda W.

    1987-01-01

    Discusses three new advances in the use of optical disc technology in education. Describes the storage formats and capabilities of the videodisc, the compact disc, and the optical write-once disc. Contrasts the three technologies in terms of their production requirements, the hardware involved, and some projected applications in education. (TW)

  16. Binder-free network-enabled MoS2-PPY-rGO ternary electrode for high capacity and excellent stability of lithium storage

    NASA Astrophysics Data System (ADS)

    Xie, D.; Wang, D. H.; Tang, W. J.; Xia, X. H.; Zhang, Y. J.; Wang, X. L.; Gu, C. D.; Tu, J. P.

    2016-03-01

    A unique MoS2-based composite composed of MoS2 nanosheets wrapped by a conductive polypyrrole (PPY) layer and closely incorporated within reduced graphene oxide (rGO) nanosheets is prepared by all-solution method. As a free-binder electrode for lithium-ion batteries, the ternary electrode delivers an initial discharge capacity of 1428 mAh g-1, maintains 1070 mAh g-1 after 400 cycles at a current density of 200 mA g-1, and also exhibits superior rate capacity of 600 mAh g-1 at a high current density of 2000 A g-1. The enhanced electrochemical performance is attributed to the advantageous combination of the 3D hierarchically rGO skeleton and in-situ formed conductive PPY coating. This design route represents a new direction for high-performance lithium ion batteries and related energy storage application with advanced nanostructured materials.

  17. Storage Ring Optics Measurement, Model, and Correction

    SciTech Connect

    Yan, Yiton T.; /SLAC

    2007-04-04

    To improve the optics of a storage ring, it is very helpful if one has an accurate lattice model. Although the ideal lattice may serve such a purpose to some extent, in most cases, real accelerator optics improvement requires accurate measurement of optics parameters. In this section, we present precision measurements of a complete set of linear orbits from which we can form a linear optics model to match the linear optics of the real machine. We call such a model a virtual machine. We have used a model-independent analysis (MIA) for accurate orbit and phase advance measurement and then used an SVD-enhanced Least Square fitting for building accurate virtual models for PEP-II e+, e- storage rings. The MIA virtual machine matches very well the real-machine linear optics including dispersion. It has successfully improved PEP-II beta beats, linear couplings, half-integer working tunes, and dispersion.

  18. Optical storage: Financial management and budget applications

    SciTech Connect

    Morris, J.D.; Emrich, M.L.

    1988-10-01

    Recent optical storage technology advances have improved the micro-computer's ability to handle large quantities of data. This paper will explain the evolution of this technology including the state of the art. The factors involved in this evolution will be described, namely the division of research into three distinct areas: Compact Disk Read Only Memory (CD-ROM); Write Once Read Many (WORM); and Erasable Optical Storage (EOS). The future implications of these areas will be reported. In addition, practical applications that utilize optical media in the financial environment will be highlighted. 3 figs., 1 tab., 10 refs.

  19. Cobalt carbonate dumbbells for high-capacity lithium storage: A slight doping of ascorbic acid and an enhancement in electrochemical performances

    NASA Astrophysics Data System (ADS)

    Zhao, Shiqiang; Wei, Shanshan; Liu, Rui; Wang, Yuxi; Yu, Yue; Shen, Qiang

    2015-06-01

    Synthesis of materials with desirable nanostructures is a hot research topic owing to their enhanced performances in contrast to the bulk counterparts. Herein, dumbbell-shaped cobalt carbonate (CoCO3) nano architectures and the bulk counterpart of CoCO3 rhombohedra are prepared via a facile hydrothermal route in the presence and absence of ascorbic acid (AA), respectively. By comparison, it has been found that: the addition of AA in the hydrothermal crystallization system changes the shape of the building blocks from Co2CO3(OH)2 nanosheets to CoCO3 nanoparticles, and then further influences the final configuration of the products. When applied as anodes of lithium ion batteries, CoCO3 dumbbells deliver a 100th capacity of 1042 mAh g-1 at 200 mA g-1 and even exhibit a long-term value of 824 mAh g-1 over 500 cycles at 1000 mA g-1, which are much higher than the rhombohedral counterparts with corresponding 540 and 481 mAh g-1 respectively. The much higher capacity, better cycling stability and enhanced rate performance of CoCO3 dumbbells can be attributed to the higher specific surface area, smaller charge transport resistance and better structure stability resulting from the slight doping (∼4.6 wt%) of AA, and also relate with a novel lithium storage mechanism in CoCO3.

  20. Integrated 3D porous C-MoS2/nitrogen-doped graphene electrode for high capacity and prolonged stability lithium storage

    NASA Astrophysics Data System (ADS)

    Xie, D.; Tang, W. J.; Xia, X. H.; Wang, D. H.; Zhou, D.; Shi, F.; Wang, X. L.; Gu, C. D.; Tu, J. P.

    2015-11-01

    Scrupulous design and fabrication of advanced anode materials are of great importance for developing high-performance lithium ion batteries. Herein, we report a facile strategy for construction of free-standing and free-binder 3D porous carbon coated MoS2/nitrogen-doped graphene (C-MoS2/N-G) integrated electrode via a hydrothermal-induced self-assembly process. The preformed carbon coated MoS2 is strongly anchored on the porous nitrogen-doped graphene aerogel architecture. As an anode for lithium ion batteries, the C-MoS2/N-G electrode delivers a high first discharge capacity of 1600 mAh g-1 and maintains 900 mAh g-1 after 500 cycles at a current density of 200 mA g-1. Impressively, superior high-rate capability is achieved for the C-MoS2/N-G with a reversible capacity of 500 mAh g-1 at a high current density of 4000 mA g-1. Furthermore, the lithium storage mechanism of the obtained integrated electrode is investigated by ex-situ X-ray photoelectron spectroscopy and transmission electron microscopy in detail.

  1. Liquid crystals for holographic optical data storage.

    PubMed

    Matharu, Avtar S; Jeeva, Shehzad; Ramanujam, P S

    2007-12-01

    A tutorial review is presented to inform and inspire the reader to develop and integrate strong scientific links between liquid crystals and holographic data storage, from a materials scientist's viewpoint. The principle of holographic data storage as a means of providing a solution to the information storage demands of the 21st century is detailed. Holography is a small subset of the much larger field of optical data storage and similarly, the diversity of materials used for optical data storage is enormous. The theory of polarisation holography which produces holograms of constant intensity, is discussed. Polymeric liquid crystals play an important role in the development of materials for holographic storage and photoresponsive materials based on azobenzene are targeted for discussion due to their ease of photo-reversion between trans- and cis-states. Although the final polymer may not be liquid crystalline, irradiation can induce ordered domains. The mesogens act in a co-operative manner, enhancing refractive indices and birefringences. Surface relief gratings are discussed as a consequence of holographic storage. Cholesteric polymers comprising azobenzene are briefly highlighted. Irradiation causing cis-trans-isomerisation can be used to control helix pitch. A brief mention of liquid crystals is also made since these materials may be of future interest since they are optically transparent and amenable to photo-induced anisotropy. PMID:17982514

  2. Optical CDMA system using bacteriorhodopsin for optical data storage

    PubMed

    Bae; Yang; Jin; Lee; Park

    1999-11-01

    An optical CDMA (code division multiple access) system for the optical data storage using bacteriorhodopsin (BR) is reported as an application of the BR materials. The desired signal of multiple input can be recorded and reconstructed by use of orthogonal codes. An experimental setup is proposed and demonstrated. PMID:10585180

  3. Holographic Optical Storage Using Photorefractive Polymers

    NASA Technical Reports Server (NTRS)

    Hayden, L. Michael; Strutz, Shane J.; Harris, Kristi; Ayachitula, Rajani

    2000-01-01

    The task for this report is to perform the basic research and develop a prototype benchtop holographic optical storage system based on photochromic and/or photorefractive polymers so that both permanent and erasable images may be stored and retrieved in the same mixed polymer medium. The task consist of: assembly and setup of the benchtop holographic storage system, including lasers, optics, and other ancillary equipment in a laboratory setting; and research and development of a suitable polymer matrix that will allow practical storage and retrieval of digital data. This will necessitate molecular design of the matrices involved and subsequent physics test to verify the characteristics of the matrices provide practical storage and retrieval.

  4. Optical Digital Disk Storage: An Application for News Libraries.

    ERIC Educational Resources Information Center

    Crowley, Mary Jo

    1988-01-01

    Describes the technology, equipment, and procedures necessary for converting a historical newspaper clipping collection to optical disk storage. Alternative storage systems--microforms, laser scanners, optical storage--are also retrieved, and the advantages and disadvantages of optical storage are considered. (MES)

  5. Optical Data Storage Capabilities of Bacteriorhodopsin

    NASA Technical Reports Server (NTRS)

    Gary, Charles

    1998-01-01

    We present several measurements of the data storage capability of bacteriorhodopsin films to help establish the baseline performance of this material as a medium for holographic data storage. In particular, we examine the decrease in diffraction efficiency with the density of holograms stored at one location in the film, and we also analyze the recording schedule needed to produce a set of equal intensity holograms at a single location in the film. Using this information along with the assumptions about the performance of the optical system, we can estimate potential data storage densities in bacteriorhodopsin.

  6. Optical storage media data integrity studies

    NASA Technical Reports Server (NTRS)

    Podio, Fernando L.

    1994-01-01

    Optical disk-based information systems are being used in private industry and many Federal Government agencies for on-line and long-term storage of large quantities of data. The storage devices that are part of these systems are designed with powerful, but not unlimited, media error correction capacities. The integrity of data stored on optical disks does not only depend on the life expectancy specifications for the medium. Different factors, including handling and storage conditions, may result in an increase of medium errors in size and frequency. Monitoring the potential data degradation is crucial, especially for long term applications. Efforts are being made by the Association for Information and Image Management Technical Committee C21, Storage Devices and Applications, to specify methods for monitoring and reporting to the user medium errors detected by the storage device while writing, reading or verifying the data stored in that medium. The Computer Systems Laboratory (CSL) of the National Institute of Standard and Technology (NIST) has a leadership role in the development of these standard techniques. In addition, CSL is researching other data integrity issues, including the investigation of error-resilient compression algorithms. NIST has conducted care and handling experiments on optical disk media with the objective of identifying possible causes of degradation. NIST work in data integrity and related standards activities is described.

  7. Optical Imaging versus Paper Records Storage.

    ERIC Educational Resources Information Center

    Baldygo, Robert

    1999-01-01

    States that the maintenance and storage of paper documents has many inherent weaknesses, including hidden costs and attached risks. Asserts that document imaging is a viable, up-to-date technology that could eliminate many of these costs and risks. Describes the system benefits, scope, requirements, and costs and the legality of optically stored…

  8. Challenges and opportunities for optical storage

    NASA Astrophysics Data System (ADS)

    Chen, Di

    2005-09-01

    Optical technique for data storage was driven from the challenges to achieve data storage performance required by the user. The first attempt to address the recording density improvement over HDD using magneto-optic technology started over thirty years ago. Subsequent efforts to develop 15", 12" and 5 and 1/4" WORM disc drives met with limited success. Advances in semiconductor lasers, lithography, and auto focusing and tracking techniques finally allow the development of the Compact Disc to answer the call for improvement in audio recording technology and data distribution in mid to late 1980. Recordable and erasable technology then followed with the introduction of CD-R, CD-RW and MO drives and media. By early 1990, advances in high density recording with the use of shorter wavelength lasers, larger n.a. lenses, improved lithographic and data compression techniques, allows the development of 4.7 GB DVD drives and discs to answer the challenge for recording 2-hour high quality movies on a CD size disc. Recordable and erasable DVD became available in 2000, and Dual Layer DVD was introduced last year . With the advent of HDTV and movie in recent years, Storage of 25 GB data in a DVD disc is needed. Blue-ray and HD-DVD are the leading technologies to answer this challenge. Looking to the future, optical storage areal density of one to two orders of magnitude improvement will be required to compete with HDD which is now reaching 133 Gb/in2 . In addition, high data transfer rate of 1Gb/s, data security, copy protection, ease of use, cost and standards issues sums up the monumental challenges facing the optical recording industry in the years to come. Some of the leading technologies, such as multi-layer, new encoding schemes, volume recording, near-field optics, micro-optics, domain expansion, UV laser, holographic storage, could provide the answers. Meeting these challenges, optical storage could become the dominant recording technology to satisfy the data storage

  9. Optical storage characters of bacteriorhodopsin molecule film

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Yang, Qing; Wu, Hongcai; Hou, Xun

    2002-04-01

    The photochromic retinal protein bacteriorhodopsin (BR) is found in the cell membrane of Halobacterium salinarium. It is the key protein for photosynthetic growth of H.salinarium. BR shows an exceptional stability towards chemical, thermal, and photochemical degradation. The photochromic properties of Bacteriorhodopsin provide the possibility of application in optical information storage. Photoexcition of the O-state of BR, which has an all-trans confirmation, leads to a state with 9-cis configuration, which is thermally stable. The 9-cis containing photoproduct of the O-state was named P-state. It absorbs at 490 nm and can be photochemically reconverted to the initial state. We propose a system of optical information storage in a BR polymer film, which is a reversible optical data recording material and can be rewritten over 106 times without degradation of the film. A three-wavelength EDRAW (Erase Direct Read After Write) experiment was performed. The photoexcited P(490) state shows a permanent storage property confirmed by our contrast ratio experiments. The result of long-term information storage in BR films more than 1 year is obtained.

  10. A biometric access personal optical storage device

    NASA Astrophysics Data System (ADS)

    Davies, David H.; Ray, Steve; Gurkowski, Mark; Lee, Lane

    2007-01-01

    A portable USB2.0 personal storage device that uses built-in encryption and allows data access through biometric scanning of a finger print is described. Biometric image derived templates are stored on the removable 32 mm write once (WO) media. The encrypted templates travel with the disc and allow access to the data providing the biometric feature (e.g. the finger itself) is present. The device also allows for export and import of the templates under secure key exchange protocols. The storage system is built around the small form factor optical engine that uses a tilt arm rotary actuator and front surface media.

  11. Optical Data Storage in Acid Red Dyes

    NASA Astrophysics Data System (ADS)

    Sankar, Deepa; Palanisamy, P. K.

    High-density optical data storage is a current field gaining importance where research work is done in abundance to bring about holographic CDs to light. Dye-doped gelatin films are promising candidates as recording materials for holographic data storage because of the ease of preparation and low cost. In this report we suggest some acid red dyes as useful recording materials for optical data storage. Acid red dyes namely Acid Red 73 and Acid Red 114 that are completely water-soluble are used to sensitize gelatin thin films for data storage. These dyes have their absorption peak around 514 nm. Two coherent beams of Argon ion laser (514.5 nm) are used to form the grating in the dye-sensitized gelatin films. The grating formed is found to be permanent. The diffraction efficiency of each material as a function of different parameters like dye concentration, writing beam intensities and their ratios and spatial frequency has been studied and presented. An attempt to store data in the sample has been made.

  12. A virtual network computer's optical storage virtualization scheme

    NASA Astrophysics Data System (ADS)

    Wang, Jianzong; Hu, Huaixiang; Wan, Jiguang; Wang, Peng

    2008-12-01

    In this paper, we present the architecture and implementation of a virtual network computers' (VNC) optical storage virtualization scheme called VOSV. Its task is to manage the mapping of virtual optical storage to physical optical storage, a technique known as optical storage virtualization. The design of VOSV aims at the optical storage resources of different clients and servers that have high read-sharing patterns. VOSV uses several schemes such as a two-level Cache mechanism, a VNC server embedded module and the iSCSI protocols to improve the performance. The results measured on the prototype are encouraging, and indicating that VOSV provides the high I/O performance.

  13. Legal and records management issue of Optical Disk Storage media

    SciTech Connect

    Nusbaum, A.

    1991-01-01

    The advent of optical storage has made the digital storage of documents a viable option from both a practical and legal perspective. However, the availability of Optical Disk Storage raises questions regarding the destruction of the stored records and standards of longevity, and the admissibility in court of records produced from optical storage has not been tested. This paper will attempt to address these issues. 6 refs.

  14. Realization of high capacity transmission in fiber optic communication systems using Absolute Polar Duty Cycle Division Multiplexing (AP-DCDM) technique

    NASA Astrophysics Data System (ADS)

    Malekmohammadi, Amin; Mahdiraji, Ghafour Amouzad; Abas, Ahmad Fauzi; Abdullah, Mohamad Khazani; Mokhtar, Makhfudzah; Rasid, Mohd Fadlee A.

    2009-08-01

    An electrical multiplexing technique, namely Absolute Polar Duty Cycle Division Multiplexing (AP-DCDM) is reported for high-speed optical fiber communication systems. It is demonstrated that 40 Gb/s (4 × 10 Gb/s) AP-DCDM system shows a clear advantage over conventional 40 Gb/s RZ-OOK with 50% duty cycle in terms of dispersion tolerance and spectral efficiency. At 40 Gb/s its tolerance to chromatic dispersion (CD) is 124 ps/nm and 194 ps/nm for the worst and the best user, respectively. These values are higher than that of 40 Gb/s RZ-OOK, which is around 100 ps/nm. The spectral efficiency, receiver sensitivity and OSNR for different number of channels are discussed. Comparison against other modulation formats namely duobinary, Non-Return-to-Zero (NRZ)-OOK and RZ-Differential Quadrature Phase-Shift Keying (RZ-DQPSK) at 40 Gb/s are made. It is shown that AP-DCDM has the best receiver sensitivity (-32 dBm) and better CD tolerance (±200 ps/nm) than NRZ-OOK and RZ-DQPSK. In reference to duobinary, AP-DCDM has better receiver sensitivity but worse dispersion tolerance.

  15. Balloon borne optical disk mass storage system

    NASA Technical Reports Server (NTRS)

    Vanek, M. D.; Jennings, D. A.

    1991-01-01

    An on-board data recording system for balloon-borne interferometer using a vacuum operable, ruggedized WORM optical drive is presented. This system, as presently under development, provides 320 Mbytes of data storage (or approximately 11 hrs at the 64 kbits/sec telemetry rate of the experiment). It has the capability of recording the unmodified telemetry bit system as transmitted or doing some preprocessing of the data onboard. The system is compact and requires less than 28 watts of battery power to operate.

  16. Research Studies on Advanced Optical Module/Head Designs for Optical Data Storage

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Preprints are presented from the recent 1992 Optical Data Storage meeting in San Jose. The papers are divided into the following topical areas: Magneto-optical media (Modeling/design and fabrication/characterization/testing); Optical heads (holographic optical elements); and Optical heads (integrated optics). Some representative titles are as follow: Diffraction analysis and evaluation of several focus and track error detection schemes for magneto-optical disk systems; Proposal for massively parallel data storage system; Transfer function characteristics of super resolving systems; Modeling and measurement of a micro-optic beam deflector; Oxidation processes in magneto-optic and related materials; and A modal analysis of lamellar diffraction gratings in conical mountings.

  17. Storage Technology: A Review of Options and Their Implications for Electronic Publishing.

    ERIC Educational Resources Information Center

    Arnold, Stephen E.

    1991-01-01

    Describes computer storage devices and suggests implications for electronic publishing. Highlights include magnetic storage media, including digital audio tape (DAT); high-capacity magnetic drives; optical storage technologies, including CD-ROM and WORM; magneto-optical drives; and a sidebar that discusses other storage technologies. (21…

  18. Experimental study of optical storage characteristics of photochromic material: pyrrylfulgide

    NASA Astrophysics Data System (ADS)

    Lei, Ming; Yao, Baoli; Chen, Yi; Han, Yong; Wang, Congmin; Wang, Yingli; Menke, Neimule; Chen, Guofu; Fan, Meigong

    2003-04-01

    Optical data storage is a frontier in the information science. Currently, there are mainly two kinds of storage materials, i.e., thermal-optic and photonic materials. The storage methods are divided into serial and parallel modes. In the market, the mature technique is CD-RW, which uses the thermal-optic material and serial method. The storage density of the CD-RW is restricted by the size of material particles, the conduction of heat, etc. Besides, the recording speed is seriously limited by the process of heating. Photonic materials and parallel method will be the trend in the optical data storage. Because it is based on the photon reaction on the molecule scale, the storage density and speed will be greatly increased. In this paper, a new kind of organic photochromic material -- pyrrylfulgide was studied. A parallel optical data storage system was established. Using the pyrrylfulgide/PMMA film as a recording medium, micro-images and binary digital information could be recorded, readout and erased in this parallel system. The recorded information on the film can be kept for at least 8 months in dark at room temperature. So far, the storage density is 3 x 107 bit/cm2.

  19. Optical Storage Interactive Simulator (oasis): An Interactive Tool for the Analysis of Page-Oriented Optical Memories.

    PubMed

    Betzos, G A; Porter, M S; Hutton, J F; Mitkas, P A

    1998-09-10

    Page-oriented optical memories combine high capacity with massive data-transfer rates and could provide the next generation of secondary storage systems. Several technological barriers need to be overcome before these memories become commercial products. One is the need for efficient interfaces to electronic computers. To assist in the analysis of all issues pertaining to such an interface, we have developed the optical storage interactive simulator (oasis), an interactive software tool. oasis can simulate data-encoding schemes, noise sources present in a particular memory system, and data-recovery mechanisms. Bit-error rates and other useful statistics can also be measured. The user has the option of studying the effects of individual error sources to the system output or of applying several of them in any order dictated by the system architecture. This multifaceted analysis will assist the user in evaluating the effectiveness of a particular error-correcting code and choosing the right one for the system. PMID:18286108

  20. Multiplexed Holographic Optical Data Storage In Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Ozcan, Meric; Smithey, Daniel T.; Crew, Marshall

    1998-01-01

    The optical data storage capacity of photochromic bacteriorhodopsin films is investigated by means of theoretical calculations, numerical simulations, and experimental measurements on sequential recording of angularly multiplexed diffraction gratings inside a thick D85N BR film.

  1. Security optical data storage in Fourier holograms.

    PubMed

    Su, Wei-Chia; Chen, Yu-Wen; Chen, Yu-Jen; Lin, Shiuan-Huei; Wang, Li-Karn

    2012-03-20

    We have proposed and demonstrated a holographic security storage system that is implemented with a shift multiplexing technique. The security function of this storage system is achieved by using a microdiffuser (MD) for random phase encoding of the reference beams. The apparatus of random phase encoding in this system offers an additional and flexible function during the recording processes. The system can generate holographic security memory or nonsecurity holographic memory via using the MD or not. The storage capacity and the average signal-to-noise value of the security storage system are 16 bits/μm(2) and 3.5, respectively. Lateral shifting selectivity in this holographic security storage system is theoretically analyzed and experimentally investigated. PMID:22441475

  2. Achievements in optical data storage and retrieval

    NASA Technical Reports Server (NTRS)

    Nelson, R. H.; Shuman, C. A.

    1977-01-01

    The present paper deals with the current achievements in two technology efforts, one of which is a wideband holographic recorder which uses multichannel recording of data in the form of holograms on roll film for storage and retrieval of large unit records at hundreds of megabit per second. The second effort involves a system (termed DIGIMEN) which uses binary spot recording on photographic film in the form of microfiche to provide a mass storage capability with automatic computer-controlled random access to stored records. Some potential design improvements are noted.

  3. Optical Digital Disks as Mass Storage Media.

    ERIC Educational Resources Information Center

    Boss, Richard W.

    1983-01-01

    Describes the optical digital disk, which stores machine-readable information in digitized form, and discusses their production, cost, present and future applications. The major companies currently active in the disk field are noted. (MBR)

  4. Bacteriorhodopsin films for optical signal processing and data storage

    NASA Technical Reports Server (NTRS)

    Walkup, John F. (Principal Investigator); Mehrl, David J. (Principal Investigator)

    1996-01-01

    This report summarizes the research results obtained on NASA Ames Grant NAG 2-878 entitled 'Investigations of Bacteriorhodopsin Films for Optical Signal Processing and Data Storage.' Specifically we performed research, at Texas Tech University, on applications of Bacteriorhodopisin film to both (1) dynamic spatial filtering and (2) holographic data storage. In addition, measurements of the noise properties of an acousto-optical matrix-vestor multiplier built for NASA Ames by Photonic Systems Inc. were performed at NASA Ames' Photonics Laboratory. This research resulted in two papers presented at major optical data processing conferences and a journal paper which is to appear in APPLIED OPTICS. A new proposal for additional BR research has recently been submitted to NASA Ames Research Center.

  5. Micro-optic lens for data storage

    NASA Technical Reports Server (NTRS)

    Milster, T. D.; Trusty, R. M.; Wang, M. S.; Froehlich, F. F.; Erwin, J. Kevin

    1991-01-01

    A new type of microlens for data storage applications that has improved off-axis performance is described. The lens consists of a micro Fresnel pattern on a curved substrate. The radius of the substrate is equal to the focal length of the lens. If the pattern and substrate are thin, the combination satisfies the Abbe sine condition. Therefore, the lens is free of coma. We analyze a 0.5 numerical aperture, 0.50 mm focal length lens in detail. A 0.16 numerical aperture lens was fabricated holographically, and results are presented.

  6. Method and apparatus for bistable optical information storage for erasable optical disks

    DOEpatents

    Land, Cecil E.; McKinney, Ira D.

    1990-01-01

    A method and an optical device for bistable storage of optical information, together with reading and erasure of the optical information, using a photoactivated shift in a field dependent phase transition between a metastable or a bias-stabilized ferroelectric (FE) phase and a stable antiferroelectric (AFE) phase in an lead lanthanum zirconate titanate (PLZT). An optical disk contains the PLZT. Writing and erasing of optical information can be accomplished by a light beam normal to the disk. Reading of optical information can be accomplished by a light beam at an incidence angle of 15 to 60 degrees to the normal of the disk.

  7. Method and apparatus for bistable optical information storage for erasable optical disks

    DOEpatents

    Land, C.E.; McKinney, I.D.

    1988-05-31

    A method and an optical device for bistable storage of optical information, together with reading and erasure of the optical information, using a photoactivated shift in a field dependent phase transition between a metastable or a bias-stabilized ferroelectric (FE) phase and a stable antiferroelectric (AFE) phase in a lead lanthanum zirconate titanate (PLZT). An optical disk contains the PLZT. Writing and erasing of optical information can be accomplished by a light beam normal to the disk. Reading of optical information can be accomplished by a light beam at an incidence angle of 15 to 60 degrees to the normal of the disk. 10 figs.

  8. ORNL concept would greatly increase optical data storage

    SciTech Connect

    Not Available

    1990-01-01

    ORNL researchers have developed a technique, surface-enhanced Raman optical data storage (SERODS), which uses the light-emitting properties of molecules to pack considerably more information into compact discs. This new technology has the potential to store 10 days of music-instead of just 90 minutes-on a single disc.

  9. Optical Disk for Digital Storage and Retrieval Systems.

    ERIC Educational Resources Information Center

    Rose, Denis A.

    1983-01-01

    Availability of low-cost digital optical disks will revolutionize storage and retrieval systems over next decade. Three major factors will effect this change: availability of disks and controllers at low-cost and in plentiful supply; availability of low-cost and better output means for system users; and more flexible, less expensive communication…

  10. Interactive Optical Disc Systems: Part 1: Analog Storage.

    ERIC Educational Resources Information Center

    Hessler, David W.

    1984-01-01

    Details distinction between digital and analog data, advantages of analog storage, and optical disc use to store analog data. Configuration and potential of three levels of laser disc systems are explained. Selection of display devices for use with laser disc systems and accessing audio data are addressed. (Continued in next issue.) (EJS)

  11. Optical distortions in electron/positron storage rings

    SciTech Connect

    Brown, K.L.; Donald, M.; Servranckx, R.

    1983-01-01

    We have studied the optical distortions in the PEP electron/positron storage ring for various optical configurations using the computer programs DIMAT, HARMON, PATRICIA, and TURTLE. The results are shown graphically by tracing several thousand trajectories from one interaction region to the next using TURTLE and by tracing a few selected rays several hundred turns using the programs DIMAT and PATRICIA. The results show an interesting correlation between the calculated optical cleanliness of a particular lattice configuration and the observed operating characteristics of the machine.

  12. High capacity aerodynamic air bearing (HCAB) for laser scanning applications

    NASA Astrophysics Data System (ADS)

    Coleman, Sean M.

    2005-08-01

    A high capacity aerodynamic air bearing (HCAB) has been developed for the laser scanning market. The need for increasing accuracies in the prepress and print plate-making market is causing a shift from ball bearing to air bearing scanners. Aerostatic air bearings are a good option to meet this demand for better performance however, these bearings tend to be expensive and require an additional air supply, filtering and drying system. Commercially available aerodynamic bearings have been typically limited to small mirrors, on the order of 3.5" diameter and less than 0.5" thick. A large optical facet, hence a larger mirror, is required to generate the high number of pixels needed for this type of application. The larger optic necessitated the development of a high capacity 'self-generating' or aerodynamic air bearing that would meet the needs of the optical scanning market. Its capacity is rated up to 6.0" diameter and 1.0" thick optics. The performance of an aerodynamic air bearing is better than a ball bearing and similar to an aerostatic air bearing. It retains the low costs while eliminating the need for ancillary equipment required by an aerostatic bearing.

  13. Surface-Enhanced Raman Optical Data Storage system

    DOEpatents

    Vo-Dinh, T.

    1991-03-12

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System are disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal. 5 figures.

  14. Surface-enhanced raman optical data storage system

    DOEpatents

    Vo-Dinh, Tuan

    1991-01-01

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System is disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal.

  15. Optical information storage in PLZT thin films

    SciTech Connect

    Land, C.E.

    1989-01-01

    The feasibility of storing and reading high density optical information in lead zirconate titanate (PZT) and in lead lanthanum zirconate titanate (PLZT) thin films depends on both the longitudinal electrooptic coefficients and the photosensitivities of the films. This paper describes the methods used to measure both the longitudinal electrooptic effects and the photosensitivities of the thin films. The results of these measurements were used to evaluate a longitudinal quadratic electrooptic R coefficient, a linear electrooptic r/sub c/ coefficient and the wavelength dependence of the photosensitivity of a composition of PZT polycrystalline thin film. The longitudinal electrooptic R and r/sub c/ coefficients are about an order of magnitude less than the transverse R and R/sub c/ coefficients of the bulk ceramics of similar compositions. This is attributed to clamping of the film by the rigid substrate. The large birefringence after poling (>10/sup /minus/2/) suggests that the optic axes of the films are preferentially oriented normal to the film surface. The techniques used for evaluating the photosensitivities of the thin films are based on measuring the photocurrent generated rather than the reduction in coercive voltage (used previously for bulk ceramics) when the film is exposed to light. The thin film photosensitivities appear to be about three orders of magnitude higher than those of bulk ceramics of similar compositions. 14 refs., 12 figs., 1 tab.

  16. New optical fibres for high-capacity optical communications.

    PubMed

    Richardson, D J

    2016-03-01

    Researchers are within a factor of 2 or so from realizing the maximum practical transmission capacity of conventional single-mode fibre transmission technology. It is therefore timely to consider new technological approaches offering the potential for more cost-effective scaling of network capacity than simply installing more and more conventional single-mode systems in parallel. In this paper, I review physical layer options that can be considered to address this requirement including the potential for reduction in both fibre loss and nonlinearity for single-mode fibres, the development of ultra-broadband fibre amplifiers and finally the use of space division multiplexing. PMID:26809569

  17. New optical fibres for high-capacity optical communications

    PubMed Central

    Richardson, D. J.

    2016-01-01

    Researchers are within a factor of 2 or so from realizing the maximum practical transmission capacity of conventional single-mode fibre transmission technology. It is therefore timely to consider new technological approaches offering the potential for more cost-effective scaling of network capacity than simply installing more and more conventional single-mode systems in parallel. In this paper, I review physical layer options that can be considered to address this requirement including the potential for reduction in both fibre loss and nonlinearity for single-mode fibres, the development of ultra-broadband fibre amplifiers and finally the use of space division multiplexing. PMID:26809569

  18. Electron trapping optical data storage system and applications

    NASA Technical Reports Server (NTRS)

    Brower, Daniel; Earman, Allen; Chaffin, M. H.

    1993-01-01

    A new technology developed at Optex Corporation out-performs all other existing data storage technologies. The Electron Trapping Optical Memory (ETOM) media stores 14 gigabytes of uncompressed data on a single, double-sided 130 mm disk with a data transfer rate of up to 120 megabits per second. The disk is removable, compact, lightweight, environmentally stable, and robust. Since the Write/Read/Erase (W/R/E) processes are carried out photonically, no heating of the recording media is required. Therefore, the storage media suffers no deleterious effects from repeated W/R/E cycling. This rewritable data storage technology has been developed for use as a basis for numerous data storage products. Industries that can benefit from the ETOM data storage technologies include: satellite data and information systems, broadcasting, video distribution, image processing and enhancement, and telecommunications. Products developed for these industries are well suited for the demanding store-and-forward buffer systems, data storage, and digital video systems needed for these applications.

  19. A high capacity 3D steganography algorithm.

    PubMed

    Chao, Min-Wen; Lin, Chao-hung; Yu, Cheng-Wei; Lee, Tong-Yee

    2009-01-01

    In this paper, we present a very high-capacity and low-distortion 3D steganography scheme. Our steganography approach is based on a novel multilayered embedding scheme to hide secret messages in the vertices of 3D polygon models. Experimental results show that the cover model distortion is very small as the number of hiding layers ranges from 7 to 13 layers. To the best of our knowledge, this novel approach can provide much higher hiding capacity than other state-of-the-art approaches, while obeying the low distortion and security basic requirements for steganography on 3D models. PMID:19147891

  20. The NASA CSTI High Capacity Power Project

    NASA Technical Reports Server (NTRS)

    Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Schmitz, P.; Vandersande, J.

    1992-01-01

    The elements of the Civilian Space Technology Initiative (CSTI) High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. The overall project will develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements are presented, along with revised goals and project timelines recently developed.

  1. Light storage in a magnetically dressed optical lattice

    NASA Astrophysics Data System (ADS)

    Dudin, Y. O.; Zhao, R.; Kennedy, T. A. B.; Kuzmich, A.

    2010-04-01

    Differential Stark shift compensation for ground-state Rb87 atoms trapped in an elliptically polarized optical lattice and “magic” magnetic field was recently proposed and demonstrated experimentally by N. Lundblad [e-print arXiv:0912.1528] and analyzed theoretically by A. Derevianko [e-print arXiv:0912.3233]. Here we demonstrate enhanced hyperfine coherence times using the magic field technique. We observe coherent light storage with a 0.32-s lifetime in an atomic Rb gas confined in a one-dimensional optical lattice and magnetic field.

  2. Light storage in a magnetically dressed optical lattice

    SciTech Connect

    Dudin, Y. O.; Zhao, R.; Kennedy, T. A. B.; Kuzmich, A.

    2010-04-15

    Differential Stark shift compensation for ground-state {sup 87}Rb atoms trapped in an elliptically polarized optical lattice and 'magic' magnetic field was recently proposed and demonstrated experimentally by N. Lundblad et al. [e-print arXiv:0912.1528] and analyzed theoretically by A. Derevianko [e-print arXiv:0912.3233]. Here we demonstrate enhanced hyperfine coherence times using the magic field technique. We observe coherent light storage with a 0.32-s lifetime in an atomic Rb gas confined in a one-dimensional optical lattice and magnetic field.

  3. SERODS optical data storage with parallel signal transfer

    DOEpatents

    Vo-Dinh, Tuan

    2003-09-02

    Surface-enhanced Raman optical data storage (SERODS) systems having increased reading and writing speeds, that is, increased data transfer rates, are disclosed. In the various SERODS read and write systems, the surface-enhanced Raman scattering (SERS) data is written and read using a two-dimensional process called parallel signal transfer (PST). The various embodiments utilize laser light beam excitation of the SERODS medium, optical filtering, beam imaging, and two-dimensional light detection. Two- and three-dimensional SERODS media are utilized. The SERODS write systems employ either a different laser or a different level of laser power.

  4. SERODS optical data storage with parallel signal transfer

    DOEpatents

    Vo-Dinh, Tuan

    2003-06-24

    Surface-enhanced Raman optical data storage (SERODS) systems having increased reading and writing speeds, that is, increased data transfer rates, are disclosed. In the various SERODS read and write systems, the surface-enhanced Raman scattering (SERS) data is written and read using a two-dimensional process called parallel signal transfer (PST). The various embodiments utilize laser light beam excitation of the SERODS medium, optical filtering, beam imaging, and two-dimensional light detection. Two- and three-dimensional SERODS media are utilized. The SERODS write systems employ either a different laser or a different level of laser power.

  5. Surface-enhanced raman optical data storage system

    DOEpatents

    Vo-Dinh, Tuan

    1994-01-01

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level.

  6. Surface-Enhanced Raman Optical Data Storage system

    DOEpatents

    Vo-Dinh, T.

    1994-06-28

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level. 18 figures.

  7. High capacity image barcodes using color separability

    NASA Astrophysics Data System (ADS)

    Bulan, Orhan; Oztan, Basak; Sharma, Gaurav

    2011-01-01

    Two-dimensional barcodes are widely used for encoding data in printed documents. In a number of applications, the visual appearance of the barcode constitutes a fundamental restriction. In this paper, we propose high capacity color image barcodes that encode data in an image while preserving its basic appearance. Our method aims at high embedding rates and sacrifices image fidelity in favor of embedding robustness in regions where these two goals conflict with each other. The method operates by utilizing cyan, magenta, and yellow printing channels with elongated dots whose orientations are modulated in order to encode the data. At the receiver, by using the complementary sensor channels to estimate the colorant channels, data is extracted in each individual colorant channel. In order to recover from errors introduced in the channel, error correction coding is employed. Our simulation and experimental results indicate that the proposed method can achieve high encoding rates while preserving the appearance of the base image.

  8. The NASA CSTI High Capacity Power Program

    SciTech Connect

    Winter, J.M.

    1994-09-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil applications. During 1986 and 1987, the NASA Advanced Technology Program was responsible for maintaining the momentum of promising technology advancement efforts started during Phase I of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In 1988, the NASA Advanced Technology Program was incorporated into NASA`s new Civil Space Technology Initiative (CSTI). The CSTI program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA advanced technology project, and provides a bridge to the NASA exploration technology programs. The elements of CSTI high capacity power development include conversion systems - Stirling and thermoelectric, thermal management, power management, system diagnostics, and environmental interactions. Technology advancement in all areas, including materials, is required to provide the growth capability, high reliability and 7 to 10 years lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems while minimizing the impact of day/night operation as well as attitudes and distance from the Sun. Significant accomplishments in all of the program elements will be discussed, along with revised goals and project timelines recently developed.

  9. The NASA CSTI High Capacity Power Program

    NASA Technical Reports Server (NTRS)

    Winter, Jerry M.

    1991-01-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil applications. During 1986 and 1987, the NASA Advanced Technology Program was responsible for maintaining the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In 1988, the NASA Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA advanced technology project, and provides a bridge to the NASA exploration technology programs. The elements of CSTI high capacity power development include conversion systems: Stirling and thermoelectric, thermal management, power management, system diagnostics, and environmental interactions. Technology advancement in all areas, including materials, is required to provide the growth capability, high reliability, and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems while minimizing the impact of day/night operations as well as attitudes and distance from the Sun. Significant accomplishments in all of the program elements will be discussed, along with revised goals and project timelines recently developed.

  10. Experimental determination of storage ring optics using orbit response measurements

    NASA Astrophysics Data System (ADS)

    Safranek, J.

    1997-02-01

    The measured response matrix giving the change in orbit at beam position monitors (BPMs) with changes in steering magnet excitation can be used to accurately calibrate the linear optics in an electron storage ring [1-8]. A computer code called LOCO (Linear Optics from Closed Orbits) was developed to analyze the NSLS X-Ray Ring measured response matrix to determine: the gradients in all 56 quadrupole magnets; the calibration of the steering magnets and BPMs; the roll of the quadrupoles, steering magnets, and BPMs about the electron beam direction; the longitudinal magnetic centers of the orbit steering magnets; the horizontal dispersion at the orbit steering magnets; and the transverse mis-alignment of the electron orbit in each of the sextupoles. Random orbit measurement error from the BPMs propagated to give only 0.04% rms error in the determination of individual quadrupole gradients and 0.4 mrad rms error in the determination of individual quadrupole rolls. Small variations of a few parts in a thousand in the quadrupole gradients within an individual family were resolved. The optics derived by LOCO gave accurate predictions of the horizontal dispersion, the beta functions, and the horizontal and vertical emittances, and it gave good qualitative agreement with the measured vertical dispersion. The improved understanding of the X-Ray Ring has enabled us to increase the synchrotron radiation brightness. The LOCO code can also be used to find the quadrupole family gradients that best correct for gradient errors in quadrupoles, in sextupoles, and from synchrotron radiation insertion devices. In this way the design periodicity of a storage ring's optics can be restored. An example of periodicity restoration will be presented for the NSLS VUV Ring. LOCO has also produced useful results when applied to the ALS storage ring [8].

  11. Holographic memory module with ultra-high capacity and throughput

    SciTech Connect

    Vladimir A. Markov, Ph.D.

    2000-06-04

    High capacity, high transfer rate, random access memory systems are needed to archive and distribute the tremendous volume of digital information being generated, for example, the human genome mapping and online libraries. The development of multi-gigabit per second networks underscores the need for next-generation archival memory systems. During Phase I we conducted the theoretical analysis and accomplished experimental tests that validated the key aspects of the ultra-high density holographic data storage module with high transfer rate. We also inspected the secure nature of the encoding method and estimated the performance of full-scale system. Two basic architectures were considered, allowing for reversible compact solid-state configuration with limited capacity, and very large capacity write once read many memory system.

  12. Optical Disc Utilized As A Data Storage System For Reconnaissance

    NASA Astrophysics Data System (ADS)

    Herzog, Donald G.

    1984-01-01

    Electra-optic and Radar sensing reconnaissance systems have many advantages including remote transmission and image data processing that conventional film camera systems do not have. However, data storage and retrieval that was naturally and easily accomplished with film must now be accommodated by other techniques. The optical disc data storage and retrieval systems offer significant advantage towards fulfilling this need. This paper will provide an overview description of the technology, some of the fundamental alternatives of configuration approach, and some examples of where it may be considered in the reconnaissance system. Silver halide film has been and still is the work horse of the image based reconnaissance field. It will not be replaced in the near future either, but rather a gradual transition to total electronic systems is expected. It is not the intent of this paper to debase film, because in fact it has its advantages. We have learned to optimize its advantages and minimize its disadvantages. However optical disc systems have a definite role to play in the reconnaissance field.

  13. Rewritable three-dimensional holographic data storage via optical forces

    NASA Astrophysics Data System (ADS)

    Yetisen, Ali K.; Montelongo, Yunuen; Butt, Haider

    2016-08-01

    The development of nanostructures that can be reversibly arranged and assembled into 3D patterns may enable optical tunability. However, current dynamic recording materials such as photorefractive polymers cannot be used to store information permanently while also retaining configurability. Here, we describe the synthesis and optimization of a silver nanoparticle doped poly(2-hydroxyethyl methacrylate-co-methacrylic acid) recording medium for reversibly recording 3D holograms. We theoretically and experimentally demonstrate organizing nanoparticles into 3D assemblies in the recording medium using optical forces produced by the gradients of standing waves. The nanoparticles in the recording medium are organized by multiple nanosecond laser pulses to produce reconfigurable slanted multilayer structures. We demonstrate the capability of producing rewritable optical elements such as multilayer Bragg diffraction gratings, 1D photonic crystals, and 3D multiplexed optical gratings. We also show that 3D virtual holograms can be reversibly recorded. This recording strategy may have applications in reconfigurable optical elements, data storage devices, and dynamic holographic displays.

  14. Mechanical and optical characterization of gelled matrices during storage.

    PubMed

    Lorenzo, Gabriel; Zaritzky, Noemí; Califano, Alicia

    2015-03-01

    The effect of composition and storage time on the rheological and optical attributes of multi-component gels containing locust bean gum (LBG), low acyl (LAG) and high acyl (HAG) gellan gums, was determined using three-component mixture design. The generalized Maxwell model was used to fit experimental rheological data. Mechanical and relaxation spectra of gelled systems were determined by the type of gellan gum used, except LBG alone which behaved as a diluted gum dispersion. Storage time dependence of the gels was analyzed using the rubber elasticity theory and to determine changes in network mesh size the equivalent network approach was applied. Destabilization kinetic was obtained from light scattering results; increasing LAG content improved the long-term stability of the matrices. Almost every formulation exhibited an increment in both moduli during the first 10 days remaining practically constant thereafter or until they broke (binary mixtures with LBG); gels with HAG/LBG mixtures were the least stable. PMID:25498706

  15. High capacity 30 K remote helium cooling loop

    NASA Astrophysics Data System (ADS)

    Trollier, T.; Tanchon, J.; Icart, Y.; Ravex, A.

    2014-01-01

    Absolut System has built several 50 K remote helium cooling loops used as high capacity and very low vibration cooling source into large wavelength IR detectors electro-optical characterization test benches. MgB2 based superconducting electro-technical equipment's under development require also distributed high cooling power in the 20-30 K temperature range. Absolut System has designed, manufactured and tested a high capacity 30 K remote helium cooling loop. The equipment consists of a CRYOMECH AL325 type cooler, a CP830 type compressor package used as room temperature circulator and an intermediate LN2 bath cooling used between two recuperator heat exchangers (300 K-77 K and 77 K-20 K). A cooling capacity of 30 W @ 20 K or 80 W @ 30 K has been demonstrated on the application heat exchanger, with a 4-meter remote distance ensured by a specifically designed gas circulation flexible line. The design and the performance will be reported in this paper.

  16. High capacity heat pipe performance demonstration

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A high capacity heat pipe which will operate in one-g and in zero-g is investigated. An artery configuration which is self-priming in one-g was emphasized. Two artery modifications were evolved as candidates to achieve one-g priming and will provide the very high performance: the four artery and the eight artery configurations. These were each evaluated analytically for performance and priming capability. The eight artery configuration was found to be inadequate from a performance standpoint. The four artery showed promise of working. A five-inch long priming element test article was fabricated using the four artery design. Plexiglas viewing windows were made on each end of the heat pipe to permit viewing of the priming activity. The five-inch primary element would not successfully prime in one-g. Difficulties on priming in one-g raised questions about zero-g priming. Therefore a small test element heat pipe for verifying that the proposed configuration will self-prime in zero-g was fabricated and delivered.

  17. The NASA CSTI High Capacity Power Project

    SciTech Connect

    Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Titran, R.; Schmitz, P.; Vandersande, J.

    1994-09-01

    The SP-100 Space Nuclear Power Program was established in 1983 by DOD, DOE, and NASA as a joint program to develop technology for military and civil applications. Starting in 1986, NASA has funded a technology program to maintain the momentum of promising aerospace technology advancement started during Phase I of SP-100 and to strengthen, in key areas, the changes for successful development and growth capability of space nuclear reactor power systems for a wide range of future space applications. The elements of the CSTI High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project with develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timelines recently developed.

  18. The NASA CSTI high capacity power project

    NASA Technical Reports Server (NTRS)

    Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Titran, R.; Schmitz, P.; Vandersande, J.

    1992-01-01

    The SP-100 Space Nuclear Power Program was established in 1983 by DOD, DOE, and NASA as a joint program to develop technology for military and civil applications. Starting in 1986, NASA has funded a technology program to maintain the momentum of promising aerospace technology advancement started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for a wide range of future space applications. The elements of the Civilian Space Technology Initiative (CSTI) High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project will develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timelines recently developed.

  19. High-Capacity Communications from Martian Distances

    NASA Technical Reports Server (NTRS)

    Williams, W. Dan; Collins, Michael; Hodges, Richard; Orr, Richard S.; Sands, O. Scott; Schuchman, Leonard; Vyas, Hemali

    2007-01-01

    High capacity communications from Martian distances, required for the envisioned human exploration and desirable for data-intensive science missions, is challenging. NASA s Deep Space Network currently requires large antennas to close RF telemetry links operating at kilobit-per-second data rates. To accommodate higher rate communications, NASA is considering means to achieve greater effective aperture at its ground stations. This report, focusing on the return link from Mars to Earth, demonstrates that without excessive research and development expenditure, operational Mars-to-Earth RF communications systems can achieve data rates up to 1 Gbps by 2020 using technology that today is at technology readiness level (TRL) 4-5. Advanced technology to achieve the needed increase in spacecraft power and transmit aperture is feasible at an only moderate increase in spacecraft mass and technology risk. In addition, both power-efficient, near-capacity coding and modulation and greater aperture from the DSN array will be required. In accord with these results and conclusions, investment in the following technologies is recommended:(1) lightweight (1 kg/sq m density) spacecraft antenna systems; (2) a Ka-band receive ground array consisting of relatively small (10-15 m) antennas; (3) coding and modulation technology that reduces spacecraft power by at least 3 dB; and (4) efficient generation of kilowatt-level spacecraft RF power.

  20. Optical properties of a photopolymer film for digital holographic storage

    NASA Astrophysics Data System (ADS)

    Shin, Changwon; Kim, Junghoi; Kim, Nam; Lee, Hyojin; Kim, Eunkyoung

    2005-09-01

    Tir- and mono functional monomers were dispersed in a solution of polysulfone in organic solvent containing a photo initiator and other additives. New photopolymer film was prepared by dispersing acrylic monomer in a polysulfone matrix. The Polysulfone was adopted as a binder since it affords transparent thick films with low dimensional changes during holographic recording. Optical property of the photopolymer showed high diffraction efficiency (>90%) under an optimized optical condition at 532nm laser. The angular selectivity for angular multiplexing page oriented holographic memories (POHMs), the maximum diffraction efficiency of the material during holographic recording, the diffraction efficiency of the films as a function of an incident angle of two beams, exposure energy for saturation of the holographic material and application for holographic data storage will be discussed.

  1. High Capacity Two-Stage Coaxial Pulse Tube Cooler

    NASA Astrophysics Data System (ADS)

    Jaco, C.; Nguyen, T.; Tward, E.

    2008-03-01

    The High Capacity Cryocooler Qualification unit (HCCQ) provides large capacity cooling at both 35 K and 85 K for space applications in which focal planes and optics require cooling. The compressor is scaled from the High Energy Cryocooler (HEC) compressor and is capable of using input powers up to 700 W. The two coaxial pulse tube cold heads are integrated with the compressor into an integral cryocooler. A thermal strap between the cold heads improves efficiency and can be positioned to provide cooling for a wide range of applied loads. The cooler will be acceptance tested at space qualification levels that include thermal performance mapping over a range of reject temperatures and power levels and launch vibration testing.

  2. 3D bit-oriented optical storage in photopolymers

    NASA Astrophysics Data System (ADS)

    Orlic, Susanna; Ulm, Steffen; Eichler, Hans Joachim

    2001-01-01

    The bit-oriented data storage of conventional optical disks may be expanded into the third dimension by using microscopic reflection gratings instead of pits. Microgratings are holographically induced in a photopolymer layer. The Bragg selectivity of holographic volume gratings makes the application of multiplexing methods possible. High storage density may be achieved by combining wavelength multiplexing and multilayer storage. Wavelength multiplexing is realized by recording several gratings overlapping with write beams of different wavelengths. All gratings are recorded simultaneously in the same volume element. By translating a photopolymer sample perpendicularly to the laser beam axis during exposure, stripe-shaped microgratings are induced dynamically with constant linear velocity. The length of a grating is defined by the exposure time. Stripe-shaped gratings are required to realize an areal structure of recorded data similar to the pit-land structure of conventional disks that allows us to overtake the progress made in proceeding CD/DVD technology. Experimental results have been obtained for writing and reading of microholograms in different photopolymer materials including DuPont holographic recording films and CROP photopolymers from Polaroid.

  3. Optical image storage in ion implanted PLZT ceramics

    SciTech Connect

    Peercy, P. S.; Land, C. E.

    1980-01-01

    Optical images can be stored in transparent lead-lanthanum-zirconate-titanate (PLZT) ceramics by exposure to near-uv light with photon energies greater than the band gas energy of approx. 3.35 eV. The image storage process relies on optically induced changes in the switching properties of ferroelectric domains (photoferroelectric effect). Stored images are nonvolatile but can be erased by uniform uv illumination and simultaneous application of an electric field. Although high quality images, with contrast variations of greater than or equal to 100:1 and spatial resolution of approx. 10 ..mu..m, can be stored using the photoferroelectric effect, relatively high exposure energies (approx. 100 mJ/cm/sup 2/) are required to store these images. This large exposure energy severely limits the range of possible applications of nonvolatile image storage in PLZT ceramics. It was found in H, He, and Ar implanted PLZT that the photosensitivity can be significantly increased by ion implantation into the surface to be exposed. The photosensitivity after implantation with 5 x 10/sup 14/ 500 keV Ar/cm/sup 2/ is increased by about three orders of magnitude over that of unimplanted PLZT. The image storage process and the effect of ion implantation is presented along with a phenomenological model which describes the enhancement in photosensitivity obtained by ion implantation. This model takes into account both light- and ion implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage with light intensity for ion implanted PLZT.

  4. Research on the Design of an Optical Information Storage Sensing System Using a Diffractive Optical Element

    PubMed Central

    Cheng, Xuemin; Hao, Qun; Hou, Jianbo; Li, Xiangping; Ma, Jianshe; Gu, Min

    2013-01-01

    This paper introduces a compact optical information storage sensing system. Applications of this system include longitudinal surface plasmon resonance detection of gold nanorods with a single femtosecond laser in three-dimensional space as well as data storage. A diffractive optical element (DOE) is applied in the system to separate the recording-reading beam from the servo beam. This allows us to apply a single laser and one objective lens in a single optical path for the servo beam and the recording-reading beam. The optical system has a linear region of 8 λ, which is compatible with current DVD servo modules. The wavefront error of the optical system is below 0.03 λrms. The minimum grating period of the DOE is 13.4 μm, and the depth of the DOE is 1.2 μm, which makes fabrication of it possible. The DOE is also designed to conveniently control the layer-selection process, as there is a linear correlation between the displacement of the DOE and the layer-selection distance. The displacement of DOE is in the range of 0–6.045 mm when the thickness of the layer-selection is 0.3 mm. Experiments were performed and the results have been verified. PMID:24217360

  5. Photovoltaics for high capacity space power systems

    SciTech Connect

    Flood, D.J.

    1988-10-01

    The anticipated energy requirements of future space missions will grow by factors approaching 100 or more, particularly as a permanent manned presence is established in space. The advances that can be expected in solar array performance and lifetime, when coupled with advanced, high energy density storage batteries and/or fuel cells, will continue to make photovoltaic energy conversion a viable power generating option for the large systems of the future. The specific technologies required to satisfy any particular set of power requirements will vary from mission to mission. Nonetheless, in almost all cases the technology push will be toward lighter weight and higher efficiency, whether of solar arrays or storage devices. This paper will describe the content and direction of the current NASA program in space photovoltaic technology. The paper will also discuss projected system level capabilities of photovoltaic power systems in the context of some of the new mission opportunities under study by NASA, such as a manned lunar base, and a manned visit to Mars.

  6. Photovoltaics for high capacity space power systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.

    1988-01-01

    The anticipated energy requirements of future space missions will grow by factors approaching 100 or more, particularly as a permanent manned presence is established in space. The advances that can be expected in solar array performance and lifetime, when coupled with advanced, high energy density storage batteries and/or fuel cells, will continue to make photovoltaic energy conversion a viable power generating option for the large systems of the future. The specific technologies required to satisfy any particular set of power requirements will vary from mission to mission. Nonetheless, in almost all cases the technology push will be toward lighter weight and higher efficiency, whether of solar arrays of storage devices. This paper will describe the content and direction of the current NASA program in space photovoltaic technology. The paper will also discuss projected system level capabilities of photovoltaic power systems in the context of some of the new mission opportunities under study by NASA, such as a manned lunar base, and a manned visit to Mars.

  7. Photovoltaics for high capacity space power systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.

    1988-01-01

    The anticipated energy requirements of future space missions will grow by factors approaching 100 or more, particularly as a permanent manned presence is established in space. The advances that can be expected in solar array performance and lifetime, when coupled with advanced, high energy density storage batteries and/or fuel cells, will continue to make photovoltaic energy conversion a viable power generating option for the large systems of the future. The specific technologies required to satisfy any particular set of power requirements will vary from mission to mission. Nonetheless, in almost all cases the technology push will be toward lighter weight and higher efficiency, whether of solar arrays or storage devices. This paper will describe the content and direction of the current NASA program in space photovoltaic technology. The paper will also discuss projected system level capabilities of photovoltaic power systems in the context of some of the new mission opportunities under study by NASA, such as a manned lunar base, and a manned visit to Mars.

  8. Certification of ICI 1012 optical data storage tape

    NASA Technical Reports Server (NTRS)

    Howell, J. M.

    1993-01-01

    ICI has developed a unique and novel method of certifying a Terabyte optical tape. The tape quality is guaranteed as a statistical upper limit on the probability of uncorrectable errors. This is called the Corrected Byte Error Rate or CBER. We developed this probabilistic method because of two reasons why error rate cannot be measured directly. Firstly, written data is indelible, so one cannot employ write/read tests such as used for magnetic tape. Secondly, the anticipated error rates need impractically large samples to measure accurately. For example, a rate of 1E-12 implies only one byte in error per tape. The archivability of ICI 1012 Data Storage Tape in general is well characterized and understood. Nevertheless, customers expect performance guarantees to be supported by test results on individual tapes. In particular, they need assurance that data is retrievable after decades in archive. This paper describes the mathematical basis, measurement apparatus and applicability of the certification method.

  9. Large Format Multifunction 2-Terabyte Optical Disk Storage System

    NASA Technical Reports Server (NTRS)

    Kaiser, David R.; Brucker, Charles F.; Gage, Edward C.; Hatwar, T. K.; Simmons, George O.

    1996-01-01

    The Kodak Digital Science OD System 2000E automated disk library (ADL) base module and write-once drive are being developed as the next generation commercial product to the currently available System 2000 ADL. Under government sponsorship with the Air Force's Rome Laboratory, Kodak is developing magneto-optic (M-O) subsystems compatible with the Kodak Digital Science ODW25 drive architecture, which will result in a multifunction (MF) drive capable of reading and writing 25 gigabyte (GB) WORM media and 15 GB erasable media. In an OD system 2000 E ADL configuration with 4 MF drives and 100 total disks with a 50% ration of WORM and M-O media, 2.0 terabytes (TB) of versatile near line mass storage is available.

  10. Dynamic model of optically pumped energy storage lasers

    SciTech Connect

    Kelly, J.H.

    1980-01-01

    A dynamic, complete model of optically pumped, energy storage laser media has been developed. This model predicts stored energy density and heat deposition as a function of both time and space. The relevant physics for solid state and liquid energy storage media has been considered including non-radiative loss mechanisms such as cooperative relaxation and multiphonon relaxation, and radiation loss mechanisms such as spontaneous emission and, for one particular geometry, amplified spontaneous emission. The model was applied to two energy storage media: xenon flashlamp pumped neodymium in glass and resonantly pumped (either xeF or dye) trivalent thulium in glass. For the nonradiative losses in both Nd and Tm systems classical electromagnetic cooperative relaxation theory was used. A concentration squared dependence is predicted and a 3/2 power dependence observed. The linear dependence on concentration of an impurity having a high energy vibration predicted by multiphonon decay theory was observed for Nd in phosphate glasses. This is strong evidence for stimulated phonon emission. Measured zero-doping fluorescence lifetimes were used in the model. Measured zero-doping fluorescence lifetimes were used in the model. Comparisons of predictions with experiment are presented. Finally, the model was applied to a large aperture, active-mirror configuration Nd:glass amplifier. This necessitated including the effect of ASE on the inversion density. Because of the unique geometry of the active mirror amplifier ASE could be approximated as a parasitic oscillation which clamps the inversion at a specific level determined from small signal gain measurements. Comparisons with the measured small signal performance of several active mirrors is shown and agreement is excellent. Consequently, the model has become an on-line design tool for optimization of large aperture amplifiers.

  11. A Bibliography of the Literature on Optical Storage Technology. Final Report.

    ERIC Educational Resources Information Center

    Park, James R.

    Compiled to serve as a working tool for those involved in optical storage research, planning, and development, this bibliography contains nearly 700 references related to the optical storage and retrieval of digital computer data. Citations are divided into two major groups covering the general and patent literatures. Each citation includes the…

  12. High-Capacity Spacesuit Evaporator Absorber Radiator (SEAR)

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Phillips, Scott; Chepko, Ariane; Bue, Grant; Quinn, Gregory

    2015-01-01

    Future human space exploration missions will require advanced life support technology that can operate across a wide range of applications and environments. Thermal control systems for space suits and spacecraft will need to meet critical requirements for water conservation and multifunctional operation. This paper describes a Space Evaporator Absorber Radiator (SEAR) that has been designed to meet performance requirements for future life support systems. A SEAR system comprises a lithium chloride absorber radiator (LCAR) for heat rejection coupled with a space water membrane evaporator (SWME) for heat acquisition. SEAR systems provide heat pumping to minimize radiator size, thermal storage to accommodate variable environmental conditions, and water absorption to minimize use of expendables. We have built and tested a flight-like, high-capacity LCAR, demonstrated its performance in thermal vacuum tests, and explored the feasibility of an ISS demonstration test of a SEAR system. The new LCAR design provides the same cooling capability as prior LCAR prototypes while enabling over 30% more heat absorbing capacity. Studies show that it should be feasible to demonstrate SEAR operation in flight by coupling with an existing EMU on the space station.

  13. High-Capacity Spacesuit Evaporator Absorber Radiator (SEAR)

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Phillips, Scott; Chepko, Ariane; Bue, Grant; Quinn, Gregory

    2014-01-01

    Future human space exploration missions will require advanced life support technology that can operate across a wide range of applications and environments. Thermal control systems for space suits and spacecraft will need to meet critical requirements for water conservation and adaptability to highly variable thermal environments. This paper describes a Space Evaporator Absorber Radiator (SEAR) that has been designed to meet performance requirements for future life support systems. A SEAR system comprises a lithium chloride absorber radiator (LCAR) for heat rejection coupled with a space water membrane evaporator (SWME) for heat acquisition. SEAR systems provide heat pumping to minimize radiator size, thermal storage to accommodate variable environmental conditions, and water absorption to minimize use of expendables. We have built and tested a flightlike, high-capacity LCAR, demonstrated its performance in thermal vacuum tests, and explored the feasibility of an ISS demonstration test of a SEAR system. The new LCAR design provides the same cooling capability as prior LCAR prototypes while enabling over 30% more heat absorbing capacity. Studies show that it should be feasible to demonstrate SEAR operation in flight by coupling with an existing EMU on the space station.

  14. High-Capacity, High-Voltage Composite Oxide Cathode Materials

    NASA Technical Reports Server (NTRS)

    Hagh, Nader M.

    2015-01-01

    This SBIR project integrates theoretical and experimental work to enable a new generation of high-capacity, high-voltage cathode materials that will lead to high-performance, robust energy storage systems. At low operating temperatures, commercially available electrode materials for lithium-ion (Li-ion) batteries do not meet energy and power requirements for NASA's planned exploration activities. NEI Corporation, in partnership with the University of California, San Diego, has developed layered composite cathode materials that increase power and energy densities at temperatures as low as 0 degC and considerably reduce the overall volume and weight of battery packs. In Phase I of the project, through innovations in the structure and morphology of composite electrode particles, the partners successfully demonstrated an energy density exceeding 1,000 Wh/kg at 4 V at room temperature. In Phase II, the team enhanced the kinetics of Li-ion transport and electronic conductivity at 0 degC. An important feature of the composite cathode is that it has at least two components that are structurally integrated. The layered material is electrochemically inactive; however, upon structural integration with a spinel material, the layered material can be electrochemically activated and deliver a large amount of energy with stable cycling.

  15. Structural Inhomogeneity and Anisotropy in Optical Filters and Thin Films; Applications to Optical Storage Media.

    NASA Astrophysics Data System (ADS)

    Balasubramanian, Kunjithapatham

    Optical filters and thin film optical devices play an important role in Science and Industry. Several significant applications have emerged in optics, microelectronics and computer technology. In this work, we study some aspects of their design and applications. One class of optical fibers, known as Christiansen filters, are based on scattering phenomena in suspensions of solid particles in a liquid medium. Some new scattering filters in the visible and the near UV regions and their performance characteristics are reported here. Feasibility to fabricate such optical filters in solid matrix form is established. Some applications of these scattering filters are discussed. After an introduction to the optics of homogeneous and isotropic thin films, I discuss the general design of anisotropic thin film media and a scheme implemented to calculate their performance. Optical anisotropy, produced by the growth-induced columnar microstructure in thin films and its effects on the performance of optical filters are studied. Large shifts in the peak wavelength of a typical narrow band filter are predicted. Magneto-optical (MO) thin film media of great importance to erasable optical data storage technology are studied. An approximate technique based on a 2 x 2 matrix formalism is developed to calculate the normal incidence performance of these media. To investigate anisotropic effects, to incorporate more than one magnetic film with arbitrary orientations of magnetization, and to study oblique incidence performance, a completely general 4 x 4 matrix technique is implemented in a computer program. Effects of substrate/superstrate birefringence in the read-out signal of MO media are investigated. Several optimizing design criteria, particularly, the effectiveness in employing appropriate metal or dielectric reflector layers are studied. The influence of the plasma edge of metals in enhancing the polar Kerr rotation of MO media is discussed with illustrations. A contour plot of

  16. Flexible storage medium for write-once optical tape

    NASA Technical Reports Server (NTRS)

    Strandjord, Andrew J. G.; Webb, Steven P.; Perettie, Donald J.; Cipriano, Robert A.

    1993-01-01

    A write-once data storage media was developed which is suitable for optical tape applications. The media is manufactured using a continuous film process to deposit a ternary alloy of tin, bismuth, and copper. This laser sensitive layer is sputter deposited onto commercial plastic web as a single-layer thin film. A second layer is sequentially deposited on top of the alloy to enhance the media performance and act as an abrasion resistant hard overcoat. The media was observed to have laser write sensitivities of less than 2.0 njoules/bit, carrier-to-noise levels of greater than 50dB's, modulation depths of approximately 100 percent, read-margins of greater than 35, uniform grain sizes of less than 200 Angstroms, and a media lifetime that exceeds 10 years. Prototype tape media was produced for use in the CREO drive system. The active and overcoat materials are first sputter deposited onto three mil PET film in a single pass through the vacuum coating system, and then converted down into multiple reels of 35mm x 880m tape. One mil PET film was also coated in this manner and then slit and packaged into 3480 tape cartridges.

  17. Small form factor (SFF) optical data storage devices for mobile applications

    NASA Astrophysics Data System (ADS)

    Park, Young-Pil; Park, No-Cheol; Kim, Chul-Jin

    2005-09-01

    There are two basic requirements in the field of optical storage data devices. The first is the demand for the improvement of memory capacity to manage the increased data capacity in personal and official purposes. The second is the demand for small sized optical storage devices for mobile multimedia digital electronics, including digital camera, PDA and mobile phones. To summarize, for the sake of mobile applications, it is necessary to develop optical data storage devices which have simultaneously a large capacity and a small size. Small form factor optical disk drive (SFF ODD) is expected to become a good match for mobile applications due its advantages over other devices in cost and removability. Nowadays, many companies and research institutes including universities cooperate together in the research on SFF ODD and other related optical storage devices. Due such active researches, it is expected that SFF ODD will be widely used in mobile applications in the very near future.

  18. Optical mass-storage based on vector wave holography

    NASA Astrophysics Data System (ADS)

    Yatagai, Toyohiko; Barada, Daisuke

    2013-06-01

    Holographic data storage based on polarization techniques is proposed. Angular and shift multiplexing techniques, as well as polarization multiplexing, are developed to increase storage capacity. Some experimental results are presented.

  19. Delivery of video-on-demand services using local storages within passive optical networks.

    PubMed

    Abeywickrama, Sandu; Wong, Elaine

    2013-01-28

    At present, distributed storage systems have been widely studied to alleviate Internet traffic build-up caused by high-bandwidth, on-demand applications. Distributed storage arrays located locally within the passive optical network were previously proposed to deliver Video-on-Demand services. As an added feature, a popularity-aware caching algorithm was also proposed to dynamically maintain the most popular videos in the storage arrays of such local storages. In this paper, we present a new dynamic bandwidth allocation algorithm to improve Video-on-Demand services over passive optical networks using local storages. The algorithm exploits the use of standard control packets to reduce the time taken for the initial request communication between the customer and the central office, and to maintain the set of popular movies in the local storage. We conduct packet level simulations to perform a comparative analysis of the Quality-of-Service attributes between two passive optical networks, namely the conventional passive optical network and one that is equipped with a local storage. Results from our analysis highlight that strategic placement of a local storage inside the network enables the services to be delivered with improved Quality-of-Service to the customer. We further formulate power consumption models of both architectures to examine the trade-off between enhanced Quality-of-Service performance versus the increased power requirement from implementing a local storage within the network. PMID:23389189

  20. Optical Disks Compete with Videotape and Magnetic Storage Media: Part I.

    ERIC Educational Resources Information Center

    Urrows, Henry; Urrows, Elizabeth

    1988-01-01

    Describes the latest technology in videotape cassette systems and other magnetic storage devices and their possible effects on optical data disks. Highlights include Honeywell's Very Large Data Store (VLDS); Exabyte's tape cartridge storage system; standards for tape drives; and Masstor System's videotape cartridge system. (LRW)

  1. Information storage duration on optical carriers based on metal-polymeric recording media

    NASA Astrophysics Data System (ADS)

    Kravets, Vasyliy G.; Karpeleva, Tatyana G.; Kostenko, Igor O.

    1997-02-01

    The results of physical properties changes for metal- polymeric films at their long-term operation and storage are presented. The results of accelerated aging tests which allowed us to evaluate the lifetime of information carrier are shown. The influence of information recording mechanisms on its storage time on optical cylindrical information carrier is established.

  2. Superimposed nanostructured diffraction gratings as high capacity barcodes for biological and chemical applications

    NASA Astrophysics Data System (ADS)

    Birtwell, S. W.; Galitonov, G. S.; Morgan, H.; Zheludev, N. I.

    2008-04-01

    We describe a new non-contact high capacity optical tagging technique for bead based assays, based on the use of nanostructured barcodes. The tags are generated from a number of superimposed diffraction gratings. With one-dimensional diffraction, capacity for up to 68,000 distinguishable tags has been demonstrated, with a theoretical capacity of up to 10 9 tags. Extension into two dimensions increases this theoretical limit to 10 21 tags.

  3. Optical and holographic storage properties of F3, Cu, and Mg-doped lithium niobate

    NASA Technical Reports Server (NTRS)

    Beatty, M. E., III; Meredith, B. D.

    1978-01-01

    Several samples of iron, copper, and magnesium doped lithium niobate were tested to determine their storage properties which would be applicable to an optical data storage system and an integrated optics data preprocessor which makes use of holographic storage techniques. The parameters of interest were the diffraction efficiency, write power, write time, erase time, erase energy, and write sensitivity. Results of these parameters are presented. It was found that iron doped lithium niobate samples yielded the best results in all parameters except for a few percent higher diffraction efficiency in copper doped samples. The magnesium doped samples were extremely insensitive and are not recommended for use in holographic optical data storage and processing systems.

  4. Coherent Optical Memory with High Storage Efficiency and Large Fractional Delay

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Hsin; Lee, Meng-Jung; Wang, I.-Chung; Du, Shengwang; Chen, Yong-Fan; Chen, Ying-Cheng; Yu, Ite A.

    2013-02-01

    A high-storage efficiency and long-lived quantum memory for photons is an essential component in long-distance quantum communication and optical quantum computation. Here, we report a 78% storage efficiency of light pulses in a cold atomic medium based on the effect of electromagnetically induced transparency. At 50% storage efficiency, we obtain a fractional delay of 74, which is the best up-to-date record. The classical fidelity of the recalled pulse is better than 90% and nearly independent of the storage time, as confirmed by the direct measurement of phase evolution of the output light pulse with a beat-note interferometer. Such excellent phase coherence between the stored and recalled light pulses suggests that the current result may be readily applied to single photon wave packets. Our work significantly advances the technology of electromagnetically induced transparency-based optical memory and may find practical applications in long-distance quantum communication and optical quantum computation.

  5. Optical card with parallel readout: proposal for a new robust storage solution

    NASA Astrophysics Data System (ADS)

    Hendriks, Rob F.; Kastelijn, Aukje; de Hoog, Thomas; van der Walle, Peter; Sternbro, Andreas

    2004-09-01

    We present a new storage system that combines the advantages of solid state and optical storage for content distribution: a removable, replicable data carrier (optical card) combined with a compact reader with robust mechanics. The system basically consists of a laser light source, a scanner, an optical card and a detector. The bits on the card are represented by transparent and non-transparent areas. The detector is an image sensor enabling parallel read-out of multiple bits. In order to overcome the minimum size of a detector pixel (and multiplex more bits onto one pixel) we illuminate the medium by multiple small optical spots generated by the Talbot effect. This array of optical probes selects a specific segment of bits. The image sensor detects the selected bits from the card. By moving the optical probes the entire card can be read. We present a basic demonstration of the concept.

  6. High capacity anode materials for lithium ion batteries

    SciTech Connect

    Lopez, Herman A.; Anguchamy, Yogesh Kumar; Deng, Haixia; Han, Yongbon; Masarapu, Charan; Venkatachalam, Subramanian; Kumar, Suject

    2015-11-19

    High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.

  7. High-reliability high-performance optical data storage system architecture

    NASA Astrophysics Data System (ADS)

    Jin, Hai; Cheng, Peng; Feng, Dan; Zhou, Xinrong

    1998-08-01

    With the terabyte demands of storage in many applications, the improvement of the speed of optical disk, especially the write performance will definitely extend the scope of their applications and enhance the overall performance of computer system. One effective way to improve the speed is to use a plurality of optical disk drivers together to construct an optical storage array similar to Redundant Arrays of Independent Disks (RAID). According to the typical architecture of RAID, the most common fault tolerant RAID architecture is RAID level 1 or RAID level 5. Both are not suitable for optical storage array because RAID level 1 architecture has the most redundancy, while the write performance of RAID level 5 architecture is one-fourth of that of RAID level 0 architecture especially for the small- write problem. In this paper, we propose a high performance and high reliability optical disk array architecture with less redundancy, called Mirror Striped Disk Array (MSDA). It is a novel solution to a small write problem for disk array. MSDA stores the original data in two ways, one in a single optical disk and the other in a plurality of optical disks in the way of RAID level 0. The redundancy of whole system is less than RAID level 1 architecture but with the same reliability as RAID level 5. As the performance of RAID level 0 part of optical storage system is much higher than that of RAID level 5 in ordinary disk array, thus it avoids the write performance loss when using Mirror Striped Disk Array architecture. Because it omits the parity generation procedure when writing the new data, thus the overall performance of Mirror Striped Disk Array is the same as that of RAID level 0 architecture. Using this architecture, we can achieve the high reliability and high performance optical storage system without adding any extra redundancy and without losing any performance compared with RAID level 0 architecture but with the reliability much higher than that of RAID level 5.

  8. High capacity nickel battery material doped with alkali metal cations

    DOEpatents

    Jackovitz, John F.; Pantier, Earl A.

    1982-05-18

    A high capacity battery material is made, consisting essentially of hydrated Ni(II) hydroxide, and about 5 wt. % to about 40 wt. % of Ni(IV) hydrated oxide interlayer doped with alkali metal cations selected from potassium, sodium and lithium cations.

  9. Multilayer optical data storage by fluorescence modulation using a CW laser

    NASA Astrophysics Data System (ADS)

    Singer, Kenneth D.; Christenson, Cory W.; Saini, Anuj; Ryan, Christopher J.; Mirletz, Heather; Shiyanovskaya, Irina; Yin, Kezhen; Baer, Eric

    2015-08-01

    Optical data storage has been widely used in certain consumer applications owing to its passive and robust nature, but has failed to keep with larger industry data storage needs due to the lack of capacity. Many alternatives have been proposed and developed, such as 3D data storage using two-photon absorption that require complex and dangerous laser systems to localize the bits. In this paper, we present a method for localizing bits using a CW 405nm laser diode, in a multilayered polymer film. Data is stored by photobleaching a fluorescent dye, and the response of the material is nonlinear, despite the CW laser and absorption in the visible region. This is achieved using sub-μs pulses from the laser initiating a photothermal effect. This writing method, along with the inexpensive roll-to-roll method for making the disc, will allow for terabyte-scale optical discs using conventional commercial optics and lasers.

  10. Bistable optical information storage using antiferroelectric-phase lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Land, C.E.

    1988-11-01

    A recently discovered photostorage effect in antiferroelectric-phase (AFE-phase) lead lanthanum zirconate titanate (PLZT) compositions appears to be particularly applicable to binary optical information storage. The basis for bistable optical information storage is that exposure to near-UV or visible light shifts the electric field threshold of the phase transition between the field-induced ferroelectric (FE) phase and the stable AFE phase in the direction of the initial AFE /yields/ FE phase transition. Properties of this photoactivated shift of the FE /yields/ AFE phase transition, including preliminary photosensitivity measurements and photostorage mechanisms, are presented. Photosensitivity enhancement by ion implantation is also discussed.

  11. Optical residue addition and storage units using a Hughes liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Habiby, S. F.; Collins, S. A., Jr.

    1984-01-01

    Optical addition and storage units are described in this paper. These units are implemented using the Hughes Liquid Crystal Light Valve (LCLV) as a spatial light modulator using residue arithmetic for a numerical representation. The main hardware components of the design, besides the light valve, include an array of single-mode optical fibers that provide input information, a polarizing prism in combination with quarter-wave and half-wave retarders for residue arithmetic implementation in the adder, and a holographic array for spatial stability in the storage unit.

  12. Six-dimensional optical storage utilizing wavelength selective, polarization sensitive, and reflectivity graded Bragg reflectors

    NASA Astrophysics Data System (ADS)

    Liu, Shangqing

    2014-09-01

    An optical storage system which stores data in three spacial and three physical dimensions is designed and investigated. Its feasibility has been demonstrated by theoretical derivation and numerical calculation. This system has comprehensive advantages including very large capacity, ultrafast throughputs, relatively simple structure and compatibility with CD and DVD. It's an actually practicable technology. With two-photon absorption writing/erasing and optical coherence tomography reading, its storage capacity is over 32 Tbytes per DVD sized disk, and its reading speed is over 25 Gbits/s with high signal-to-noise ratio of over 76 dB. The larger capacity of over 1 Pbyte per disk is potential.

  13. High Capacity Data Hiding in Binary Document Images

    NASA Astrophysics Data System (ADS)

    Puhan, N. B.; Ho, A. T. S.; Sattar, F.

    In this paper, we propose a high capacity data hiding method in binary document images towards semi-fragile authentication. Achieving high capacity in binary images with strict imperceptibility criterion is found to be a difficult task. In this method, noise type pixels are selected for pixel-wise data embedding using a secret key. The data hiding process through pixel flipping introduces some background noise in watermarked images and could preserve relevant information. The reversible nature of noise pixel patterns used in flipping process enables blind detection and provides high watermark capacity illustrated in different test images. After extraction process, the background noise is removed to generate the noise-free version of the watermarked image.

  14. Recycling rice husks for high-capacity lithium battery anodes.

    PubMed

    Jung, Dae Soo; Ryou, Myung-Hyun; Sung, Yong Joo; Park, Seung Bin; Choi, Jang Wook

    2013-07-23

    The rice husk is the outer covering of a rice kernel and protects the inner ingredients from external attack by insects and bacteria. To perform this function while ventilating air and moisture, rice plants have developed unique nanoporous silica layers in their husks through years of natural evolution. Despite the massive amount of annual production near 10(8) tons worldwide, so far rice husks have been recycled only for low-value agricultural items. In an effort to recycle rice husks for high-value applications, we convert the silica to silicon and use it for high-capacity lithium battery anodes. Taking advantage of the interconnected nanoporous structure naturally existing in rice husks, the converted silicon exhibits excellent electrochemical performance as a lithium battery anode, suggesting that rice husks can be a massive resource for use in high-capacity lithium battery negative electrodes. PMID:23836636

  15. A high capacity satellite switched TDMA microwave switch matrix

    NASA Technical Reports Server (NTRS)

    Cory, B. J.; Berkowitz, M.

    1981-01-01

    A description is given of the conceptual design of a high-capacity satellite switched-time division multiple access (SS-TDMA) microwave switch matrix fabricated with GaAs monolithic microwave integrated circuits (MMICs), including integration of both microwave and control logic circuits into the monolithic design. The technology required for a 30/20 GHz communications system includes an on-board SS-TDMA switch matrix. A conceptual design study that has been completed for a wideband, high-capacity (typically 100 x 100) channel switch matrix using technology anticipated for 1987 is described, noting that the study resulted in a switch matrix design concept using a coupled crossbar architecture implemented with MMIC. The design involves basic building block MMIC, permitting flexible growth and efficient wraparound redundancy to increase reliability.

  16. Recycling rice husks for high-capacity lithium battery anodes

    PubMed Central

    Jung, Dae Soo; Ryou, Myung-Hyun; Sung, Yong Joo; Park, Seung Bin; Choi, Jang Wook

    2013-01-01

    The rice husk is the outer covering of a rice kernel and protects the inner ingredients from external attack by insects and bacteria. To perform this function while ventilating air and moisture, rice plants have developed unique nanoporous silica layers in their husks through years of natural evolution. Despite the massive amount of annual production near 108 tons worldwide, so far rice husks have been recycled only for low-value agricultural items. In an effort to recycle rice husks for high-value applications, we convert the silica to silicon and use it for high-capacity lithium battery anodes. Taking advantage of the interconnected nanoporous structure naturally existing in rice husks, the converted silicon exhibits excellent electrochemical performance as a lithium battery anode, suggesting that rice husks can be a massive resource for use in high-capacity lithium battery negative electrodes. PMID:23836636

  17. Patents and inventorship issues over the last thirty years of optical storage

    NASA Astrophysics Data System (ADS)

    Gregg, David P.

    1997-07-01

    Patents, copyrights, and other intellectual property issues such as inventorship and authorship, respectively, are of great and growing concern to the technologist. Issues concerning these matters are taken up here with emphasis on an example of optical storage technology: the invention of the pulse-modulated, optical disk system. Foreign law differs in many cases from U.S. practice and will not be considered here.

  18. Method of bistable optical information storage using antiferroelectric phase PLZT ceramics

    DOEpatents

    Land, C.E.

    1990-07-31

    A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field. 8 figs.

  19. Method of bistable optical information storage using antiferroelectric phase PLZT ceramics

    DOEpatents

    Land, Cecil E.

    1990-01-01

    A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field.

  20. Rewritable Optical Storage with a Spiropyran Doped Liquid Crystal Polymer Film.

    PubMed

    Petriashvili, Gia; De Santo, Maria Penelope; Devadze, Lali; Zurabishvili, Tsisana; Sepashvili, Nino; Gary, Ramla; Barberi, Riccardo

    2016-03-01

    Rewritable optical storage has been obtained in a spiropyran doped liquid crystal polymer films. Pictures can be recorded on films upon irradiation with UV light passing through a grayscale mask and they can be rapidly erased using visible light. Films present improved photosensitivity and optical contrast, good resistance to photofatigue, and high spatial resolution. These photochromic films work as a multifunctional, dynamic photosensitive material with a real-time image recording feature. PMID:26864876

  1. High-density optical disks for long-term information storage

    NASA Astrophysics Data System (ADS)

    Petrov, Viacheslav; Kryuchyn, Andriy; Gorbov, Ivan

    2011-09-01

    Optical discs are widely used for storage of archival data represented in a digital form. Long-term storage of information recorded on standard CDs is provided by periodical rewriting (once in 3-5 years) on the new carriers. High-stable lightsensitive materials and special reflective metal coatings are proposed to use for increasing the information storage terms of the optical discs. The conducted researches have showed that the application of vitreous chalcogenide semiconductors in optical WORM discs assures the data storage terms up to 30 years. Substantially larger terms of data storage can be realized on the optical ROM carriers. Attainment of the guaranteed data storage terms within several hundreds years is provided in such carriers by applying high-stable materials substrates and information should be represented in the form of a micro-relief structure on the substrate surface. Sapphire, quartz, silicon, glass-ceramics and other materials can be utilized for manufacturing substrates of optical BD discs (and other subsequent high-density disc formats). These materials allow creating substrates characterized with increased melting temperature, chemical and mechanical resistance. Furthermore, using the mentioned materials for substrates production permits applying high temperature materials, such as chrome and nickel, to creation of high-stable refractive layers and demonstrating the sufficient mechanical adhesion between the refractive layer and the substrate. Modern methods of thermo-lithography offers creating of nano-size images on photo-resist layer deposited on the substrates. Those images can be transformed to the nano-size relief structures on the surface of the high-stable materials substrates by techniques of reactive ion-beam etching.

  2. Characterization of bacteriorhodopsin films for optical data storage and image processing

    NASA Astrophysics Data System (ADS)

    Markov, Vladimir B.; Rohrbacher, Andreas; Lal, Amit K.; Millerd, James E.; Trolinger, James D.

    1999-06-01

    Bacteriorhodopsin (BR) has been proven to be an effective non-linear media for a variety of applications, such as optically addressable spatial light modulators, volumetric memories, optical image processing systems, optical sensors, and optical correlators. However, practical realization of such systems with BR depends upon the specific characteristics of this material. In this report we present experimental results of the time evolution and intensity dependent characteristics of a BR gelatin film. In particular we studied the spectral dependence of the optical density/refraction index modulation. A holographic technique was used to investigate the exposure characteristics of photorefraction, recording versus storage time, as well as the connection between the diffraction efficiency of the recorded grating and light induced scattering (noise)--the parameters that are of primary importance for such applications as high density memory systems and optical correlators.

  3. Storage and switching of multiple optical signals among three channels

    SciTech Connect

    Song Xiaoli; Li Aijun; Wang Lei; Kang Zhihui; Kou Jun; Wang Chunliang; Jiang Yun; Gao Jinyue; Zhang Bing

    2009-05-15

    We experimentally and theoretically demonstrate that multioptical signals can be effectively stored and retrieved by fractional stimulated Raman adiabatic passage technique in a tripod-type four-level {sup 87}Rb atomic system. The optical pulses stored can be controllably released into two of the three different channels. The restored pulses have the same frequency, polarization, and propagation direction as the writing pulses. The experimental results fit very well with the numerical simulations.

  4. Bismuth sulfide: A high-capacity anode for sodium-ion batteries

    NASA Astrophysics Data System (ADS)

    Sun, Wenping; Rui, Xianhong; Zhang, Dan; Jiang, Yinzhu; Sun, Ziqi; Liu, Huakun; Dou, Shixue

    2016-03-01

    Exploring high-performance anode materials is currently one of the most urgent issues towards practical sodium-ion batteries (SIBs). In this work, Bi2S3 is demonstrated to be a high-capacity anode for SIBs for the first time. The specific capacity of Bi2S3 nanorods achieves up to 658 and 264 mAh g-1 at a current density of 100 and 2000 mA g-1, respectively. A full cell with Na3V2(PO4)3-based cathode is also assembled as a proof of concept and delivers 340 mAh g-1 at 100 mA g-1. The sodium storage mechanism of Bi2S3 is investigated by ex-situ XRD coupled with high-resolution TEM (HRTEM), and it is found that sodium storage is achieved by a combined conversion-intercalation mechanism.

  5. 50-Gbit/s optical pulse storage ring using novel rational-harmonic modulation

    NASA Astrophysics Data System (ADS)

    Moores, J. D.; Wong, W. S.; Hall, K. L.

    1995-12-01

    50-Gbit / s, 3.8-kbit packets of optical return-to-zero data have been stored in a unidirectional fiber storage ring by use of a novel modulation scheme in which the ratio of the fundamental modulation frequency to the cavity fundamental frequency is rational (nonintegral). The modulation technique should be applicable to lasers and to soliton transmission.

  6. Issues Involved in Developing Integrated Optical Jukebox Storage Systems for Customized Applications.

    ERIC Educational Resources Information Center

    Augsburger, Wayne; McNary, Larry

    1992-01-01

    Suggests a process for evaluating and planning integrated optical jukebox storage systems. Considerations regarding architecture and system performance are summarized, and a modeling program for tailoring system response to specific applications is presented. Five robotics algorithms are examined to illustrate different hardware configurations.…

  7. Controllable high bandwidth storage of optical information in a Bose-Einstein Condensate

    NASA Astrophysics Data System (ADS)

    Jayaseelan, Maitreyi; Schultz, Justin T.; Murphree, Joseph D.; Hansen, Azure; Bigelow, Nicholas P.

    2016-05-01

    The storage and retrieval of optical information has been of interest for a variety of applications including quantum information processing, quantum networks and quantum memories. Several schemes have been investigated and realized with weak, narrowband pulses, including techniques using EIT in solid state systems and both hot and cold atomic vapors. In contrast, we investigate the storage and manipulation of strong, high bandwidth pulses in a Bose-Einstein Condensate (BEC) of ultracold 87 Rb atoms. As a storage medium for optical pulses, BECs offer long storage times and preserve the coherence properties of the input information, suppressing unwanted thermal decoherence effects. We present numerical simulations of nanosecond pulses addressing a three-level lambda system on the D2 line of 87 Rb. The signal pulse is stored as a localized spin excitation in the condensate and can be moved or retrieved by reapplication of successive control pulses. The relative Rabi frequencies and areas of the pulses and the local atomic density in the condensate determine the storage location and readout of the signal pulse. Extending this scheme to use beams with a variety of spatial modes such as Hermite- and Laguerre-Gaussian modes offers an expanded alphabet for information storage.

  8. Advanced multilayer optical data storage: origins and future prospect

    NASA Astrophysics Data System (ADS)

    Esener, Sadik

    2008-02-01

    Fifty years have elapsed since the first concepts in volumetric memories have been put forward. Nowadays, the perceived need for low cost removable TB/disk storage systems is one more time fueling the development of 3D media, recording and readout systems. This paper, by reviewing some of the key historic moments and accomplishments in the development of volumetric recording systems attempts to shine light on possible future developments and directions while paying a tribute to many of the researchers that have contributed to the development of this field: in particular to Dr. Hans J. Coufal who for many years has provided vision, guidance, and leadership by leading recent INSIC Technology Roadmap efforts and organizing this conference. He is and will be greatly missed at a time when our common dreams may become a commercial reality.

  9. Optical imaging and information storage in ion implanted ferroelectric ceramics

    SciTech Connect

    Peercy, P.S.; Land, C.E.

    1981-11-01

    Photographic images can be stored in ferroelectric-phase lead lanthanum zirconate titanate (PLZT) ceramics using a novel photoferroelectric effect. These images are nonvolatile but erasable and can be switched from positive to negative by application of an electric field. We have found that the photosensitivity of ferroelectric PLZT is dramatically improved by ion implantation into the surface exposed to image light. For example, the intrinsic photosensitivity to near-UV light is increased by as much as four orders of magnitude by coimplantation with Ar and Ne. The increased photosensitivity results from implantation-induced decreases in dark conductivity and dielectric constant in the implanted layer. Furthermore, the increased photoferroelectric sensitivity has recently been extended from the near-UV to the visible spectrum by implants of Al and Cr. Ion-implanted PLZT is the most sensitive, nonvolatile, selectively-erasable image storage medium currently known.

  10. Optical data storage; Proceedings of the Meeting, San Jose, CA, Feb. 9-14, 1992

    SciTech Connect

    Carlin, D.B.; Kay, D.B.

    1992-01-01

    The present volume on optical data storage technology discusses high-speed/high-density magneto-optic recording; a compact optical head integrated with chip elements for CD-ROM drives; disk memory systems using 1D hologram technology; transfer function characteristics of superresolving systems; servo technology for a three-beam overwritable magnetooptical disk drive; signal and noise characteristics in magnetooptical signal detection with elliptically polarized light; and simplified analysis of the readout waveform for an elliptical mark. Also discussed are magnetically induced superresolution for high-density optical disk systems, magnetic properties and microstructure in (Fe,Co)/Pt multilayer films, high-density overwrite recording for a phase-change medium using a visible-light laser diode, continuous manufacturing of thin cover sheet optical media, magnetooptic multilayers, and a three-beam magnetooptical disk drive with overwrite function.

  11. Development of a high capacity variable conductance heat pipe.

    NASA Technical Reports Server (NTRS)

    Kosson, R.; Hembach, R.; Edelstein, F.; Loose, J.

    1973-01-01

    The high-capacity, pressure-primed, tunnel-artery wick concept was used in a gas-controlled variable conductance heat pipe. A variety of techniques were employed to control the size of gas/vapor bubbles trapped within the artery. Successful operation was attained with a nominal 6-foot long, 1-inch diameter cold reservoir VCHP using ammonia working fluid and nitrogen control gas. The pipe contained a heat exchanger to subcool the liquid in the artery. Maximum transport capacity with a 46-inch effective length was 1200 watts level (more than 50,000 watt-inches) and 800 watts at 0.5-inch adverse tilt.

  12. High specific energy, high capacity nickel-hydrogen cell design

    NASA Technical Reports Server (NTRS)

    Wheeler, James R.

    1993-01-01

    A 3.5 inch rabbit-ear-terminal nickel-hydrogen cell has been designed and tested to deliver high capacity at a C/1.5 discharge rate. Its specific energy yield of 60.6 wh/kg is believed to be the highest yet achieved in a slurry-process nickel-hydrogen cell, and its 10 C capacity of 113.9 AH the highest capacity yet made at a discharge rate this high in the 3.5 inch diameter size. The cell also demonstrated a pulse capability of 180 amps for 20 seconds. Specific cell parameters, performance, and future test plans are described.

  13. Colloidal silica films for high-capacity DNA arrays

    NASA Astrophysics Data System (ADS)

    Glazer, Marc Irving

    The human genome project has greatly expanded the amount of genetic information available to researchers, but before this vast new source of data can be fully utilized, techniques for rapid, large-scale analysis of DNA and RNA must continue to develop. DNA arrays have emerged as a powerful new technology for analyzing genomic samples in a highly parallel format. The detection sensitivity of these arrays is dependent on the quantity and density of immobilized probe molecules. We have investigated substrates with a porous, "three-dimensional" surface layer as a means of increasing the surface area available for the synthesis of oligonucleotide probes, thereby increasing the number of available probes and the amount of detectable bound target. Porous colloidal silica films were created by two techniques. In the first approach, films were deposited by spin-coating silica colloid suspensions onto flat glass substrates, with the pores being formed by the natural voids between the solid particles (typically 23nm pores, 35% porosity). In the second approach, latex particles were co-deposited with the silica and then pyrolyzed, creating films with larger pores (36 nm), higher porosity (65%), and higher surface area. For 0.3 mum films, enhancements of eight to ten-fold and 12- to 14-fold were achieved with the pure silica films and the films "templated" with polymer latex, respectively. In gene expression assays for up to 7,000 genes using complex biological samples, the high-capacity films provided enhanced signals and performed equivalently or better than planar glass on all other functional measures, confirming that colloidal silica films are a promising platform for high-capacity DNA arrays. We have also investigated the kinetics of hybridization on planar glass and high-capacity substrates. Adsorption on planar arrays is similar to ideal Langmuir-type adsorption, although with an "overshoot" at high solution concentration. Hybridization on high-capacity films is

  14. New optical modeling and optical compensation for mechanical instabilities on holographic data storage system using time averaged holography

    NASA Astrophysics Data System (ADS)

    Shimada, Ken-ichi; Ishii, Toshiki; Hoshizawa, Taku; Takashima, Yuzuru

    2015-09-01

    Mechanical instabilities during recording and involved degradation of signal quality in high density and high data transfer rate holographic data storage system (HDSS) is one of the obstacles to prevent the technology from being a stable system. We analytically formulated effects of mechanical instabilities of a Galvano mirror and spindle motor on the HDSS by incorporating the concept of a time-averaged holography. Mechanical parameters such as amplitude and frequency of mechanical oscillation are related to optical parameters such as amplitude and phase of reference and signal beams. Especially, the analytical formulation led to a new method of optical and post compensation for mechanical instability during recording hologram. The optical post compensation method enables a robust implementation of HDSS against mechanical instabilities.

  15. Optical phase information writing and storage in populations of metastable quantum states

    SciTech Connect

    Djotyan, G. P.; Sandor, N.; Bakos, J. S.; Soerlei, Zs.

    2009-10-15

    We propose a scheme for robust writing and storage of optical phase information in populations of metastable states of the atoms with a tripod structure of levels by using frequency-chirped laser pulses. The method provides much longer storage times compared with the schemes based on the collective atomic spin coherences. A negligible excitation of the atom provides immunity to decoherence induced by decay of the excited states. The method is robust against small-to-medium variations in the laser pulse intensity and speed of the chirp and, being insensitive to resonance conditions, it is effective both in homogeneously and inhomogeneously broadened media.

  16. An emerging network storage management standard: Media error monitoring and reporting information (MEMRI) - to determine optical tape data integrity

    NASA Technical Reports Server (NTRS)

    Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don

    1998-01-01

    Sophisticated network storage management applications are rapidly evolving to satisfy a market demand for highly reliable data storage systems with large data storage capacities and performance requirements. To preserve a high degree of data integrity, these applications must rely on intelligent data storage devices that can provide reliable indicators of data degradation. Error correction activity generally occurs within storage devices without notification to the host. Early indicators of degradation and media error monitoring 333 and reporting (MEMR) techniques implemented in data storage devices allow network storage management applications to notify system administrators of these events and to take appropriate corrective actions before catastrophic errors occur. Although MEMR techniques have been implemented in data storage devices for many years, until 1996 no MEMR standards existed. In 1996 the American National Standards Institute (ANSI) approved the only known (world-wide) industry standard specifying MEMR techniques to verify stored data on optical disks. This industry standard was developed under the auspices of the Association for Information and Image Management (AIIM). A recently formed AIIM Optical Tape Subcommittee initiated the development of another data integrity standard specifying a set of media error monitoring tools and media error monitoring information (MEMRI) to verify stored data on optical tape media. This paper discusses the need for intelligent storage devices that can provide data integrity metadata, the content of the existing data integrity standard for optical disks, and the content of the MEMRI standard being developed by the AIIM Optical Tape Subcommittee.

  17. Towards a Flat Rotating Flexible Disk for High Speed Optical Data Storage

    NASA Astrophysics Data System (ADS)

    Gad, Abdelrasoul M. M.; Rhim, Yoon Chul

    2010-08-01

    A flexible optical disk system, which consists of a thin optical disk and a rigid stabilizer, has recently introduced as the next-generation optical storage media. The present work introduces a new design for the stabilizer that helps to hold the rotating flexible optical disk almost flat and thereby reducing its axial run-out at high rotational speeds; the new design incorporates an axisymmetrically curved active surface of the stabilizer. The combination of the stabilizer curvature and disk rotation generates moderate air-film forces that balance the disk mechanical forces and reduces the disk axial run-out considerably. With a proper combination of the stabilizer geometrical parameters, the out-of-flatness as well as the axial run-out of the disk could be reduced to less than 10 µm. The significant decrease in the axial run-out at rotational speed of 10,000 rpm is primarily due to the flatness of the disk.

  18. Static tester for characterization of phase-change, dye-polymer, and magneto-optical media for optical data storage.

    PubMed

    Mansuripur, M; Erwin, J K; Bletscher, W; Khulbe, P; Sadeghi, K; Xun, X; Gupta, A; Mendes, S B

    1999-12-01

    We have designed and built a static tester around a commercially available polarized light microscope. This device employs two semiconductor laser diodes (at 643- and 680-nm wavelengths) for the purpose of recording small marks on various media for optical data storage and for the simultaneous monitoring of the recording process. We use one of the lasers in the single-pulse mode to write a mark on the sample and operate the other laser in the cw mode to monitor the recording process. The two laser beams are brought to coincident focus on the sample through the objective lens of the microscope. The reflected beams are sent through a polarizing beam splitter and thus divided into two branches, depending on whether they are p or s polarized. In each branch the beam is further divided into two according to the wavelength. The four beams thus produced are sent to four high-speed photodetectors, and the resulting signals are used to monitor the reflectance as well as the polarization state of the beam on reflection from the sample. We provide a comprehensive description of the tester's design and operating principles. We also report preliminary results of measurements of phase-change, dye-polymer, and magneto-optical samples, which are currently of interest in the areas of writable and rewritable optical data storage. PMID:18324256

  19. Three-dimensional optical disk data storage via the localized alteration of a format hologram.

    PubMed

    McLeod, R R; Daiber, A J; Honda, T; McDonald, M E; Robertson, T L; Slagle, T; Sochava, S L; Hesselink, L

    2008-05-10

    Three-dimensional optical data storage is demonstrated in an initially homogenous volume by first recording a reflection grating in a holographic photopolymer. This causes the entire volume to be weakly reflecting to a confocal read/write head. Superposition of two or three such gratings with slightly different k-vectors creates a track and layer structure that specialized servo detection optics can use to lock the focus to these deeply-buried tracks. Writing is accomplished by locally modifying the reflectivity of the preexisting hologram. This modification can take the form of ablation, inelastic deformation via heating at the focus, or erasure via linear or two-photon continued polymerization in the previously unexposed fringes of the hologram. Storage by each method is demonstrated with up to eight data layers separated by as little as 12 microns. PMID:18470266

  20. Storage and Recall of Weak Coherent Optical Pulses with an Efficiency of 25%

    NASA Astrophysics Data System (ADS)

    Sabooni, M.; Beaudoin, F.; Walther, A.; Lin, N.; Amari, A.; Huang, M.; Kröll, S.

    2010-08-01

    We demonstrate experimentally an efficient coherent rephasing scheme for the storage and recall of weak coherent light pulses in an inhomogeneously broadened optical transition in a Pr3+:YSO crystal at 2.1 K. Precise optical pumping using a frequency stable (≈1kHz linewidth) laser is employed to create a highly controllable atomic frequency comb structure. We report single photon level storage and retrieval efficiencies of 25%, based on coherent photon-echo-type reemission in the forward direction. The high efficiency is mainly a product of our highly controllable and precise ensemble-shaping technique. The coherence property of the quantum memory is proved through interference between a super-Gaussian pulse and the emitted echo.

  1. Haloalkane-based polymeric mixtures for high density optical data storage

    NASA Astrophysics Data System (ADS)

    Castagna, Riccardo; Lucchetta, Daniele E.; Vita, Francesco; Criante, Luigino; Greci, Lucedio; Simoni, Francesco

    2008-08-01

    We present an investigation on new organic mixtures for high resolution holographic data recording. Reflection holograms were obtained via blue laser light irradiation ( λ = 457.9 nm) on photo-sensitive acrylate and 1-chloro-hexane or 1-bromo-hexane based mixtures. These haloalkanes were selected on the basis of their ability to originate phase separation from acrylate during the photo-polymerization process and for their lower refractive index with respect to the used poly-acrylate monomer. This last property allowed the achievement of a good dielectric contrast between polymer and haloalkane-rich layers. The recorded holograms have been investigated and optically characterized focusing on holographic data storage requirements. Finally, the results were compared with those concerning holographic polymer dispersed liquid crystal, already proposed for optical data storage applications.

  2. High specific energy, high capacity nickel-hydrogen cell design

    NASA Technical Reports Server (NTRS)

    Wheeler, James R.

    1993-01-01

    A 3.5 inch rabbit-ear-terminal nickel-hydrogen cell was designed and tested to deliver high capacity at steady discharge rates up to and including a C rate. Its specific energy yield of 60.6 wh/kg is believed to be the highest yet achieved in a slurry-process nickel-hydrogen cell, and its 10 C capacity of 113.9 AH the highest capacity yet of any type in a 3.5 inch diameter size. The cell also demonstrated a pulse capability of 180 amps for 20 seconds. Specific cell parameters and performance are described. Also covered is an episode of capacity fading due to electrode swelling and its successful recovery by means of additional activation procedures.

  3. High capacity demonstration of honeycomb panel heat pipes

    NASA Technical Reports Server (NTRS)

    Tanzer, H. J.

    1989-01-01

    The feasibility of performance enhancing the sandwich panel heat pipe was investigated for moderate temperature range heat rejection radiators on future-high-power spacecraft. The hardware development program consisted of performance prediction modeling, fabrication, ground test, and data correlation. Using available sandwich panel materials, a series of subscale test panels were augumented with high-capacity sideflow and temperature control variable conductance features, and test evaluated for correlation with performance prediction codes. Using the correlated prediction model, a 50-kW full size radiator was defined using methanol working fluid and closely spaced sideflows. A new concept called the hybrid radiator individually optimizes heat pipe components. A 2.44-m long hybrid test vehicle demonstrated proof-of-principle performance.

  4. Testing of a high capacity research heat pipe

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Tests were performed on a high-capacity channel-wick heat pipe to assess the transport limitations of v-grooves and the effects of boiling. The results showed that transport can vary significantly (less than 50 W) under similar conditions and the continuous boiling was observed at power levels as low as 40 W. In addition, some evidence was found to support the predictions using a groove transport model which shows that transport increases with lower groove densities and longer evaporators. However, due to transport variations, these results were not consistent throughout the program. When a glass fiber wick was installed over the grooves, a relatively low transport level was achieved (80 to 140 W). Based on these results and the identification of some potential causes for them, several design suggestions were recommended for reducing the possibility of boiling and improving groove transport.

  5. High capacity demonstration of honeycomb panel heat pipes

    NASA Technical Reports Server (NTRS)

    Tanzer, H. J.; Cerza, M. R., Jr.; Hall, J. B.

    1986-01-01

    High capacity honeycomb panel heat pipes were investigated as heat rejection radiators on future space platforms. Starting with a remnant section of honeycomb panel measuring 3.05-m long by 0.127-m wide that was originally designed and built for high-efficiency radiator fins, features were added to increase thermal transport capacity and thus permit test evaluation as an integral heat transport and rejection radiator. A series of subscale panels were fabricated and reworked to isolate individual enhancement features. Key to the enhancement was the addition of a liquid sideflow that utilizes pressure priming. A prediction model was developed and correlated with measured data, and then used to project performance to large, space-station size radiators. Results show that a honeycomb panel with 5.08-cm sideflow spacing and core modification will meet the design load of a 50 kW space heat rejection system.

  6. Stable high capacity, F-actin affinity column

    SciTech Connect

    Luna, E.J.; Wang, Y.L.; Voss, E.W. Jr.; Branton, D.; Taylor, D.L.

    1982-11-10

    A high capacity F-actin affinity matrix is constructed by binding fluorescyl-actin to rabbit anti-fluorescein IgG that is covalently bound to Sepharose 4B. When stabilized with phalloidin, the actin remains associated with the Sepharose beads during repeated washes, activates the ATPase activity of myosin subfragment 1, and specifically binds /sup 125/I-heavy meromyosin and /sup 125/I-tropomyosin. The associations between the F-actin-binding proteins are monitored both by affinity chromatography and by a rapid, low speed sedimentation assay. Anti-fluorescein IgG-Sepharose should be generally useful as a matrix for the immobilization of proteins containing accessible, covalently bound fluorescein groups.

  7. Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre

    NASA Astrophysics Data System (ADS)

    Saglamyurek, Erhan; Jin, Jeongwan; Verma, Varun B.; Shaw, Matthew D.; Marsili, Francesco; Nam, Sae Woo; Oblak, Daniel; Tittel, Wolfgang

    2015-02-01

    The realization of a future quantum Internet requires the processing and storage of quantum information at local nodes and interconnecting distant nodes using free-space and fibre-optic links. Quantum memories for light are key elements of such quantum networks. However, to date, neither an atomic quantum memory for non-classical states of light operating at a wavelength compatible with standard telecom fibre infrastructure, nor a fibre-based implementation of a quantum memory, has been reported. Here, we demonstrate the storage and faithful recall of the state of a 1,532 nm wavelength photon entangled with a 795 nm photon, in an ensemble of cryogenically cooled erbium ions doped into a 20-m-long silica fibre, using a photon-echo quantum memory protocol. Despite its currently limited efficiency and storage time, our broadband light-matter interface brings fibre-based quantum networks one step closer to reality.

  8. Nonlinear Optical Properties of Bacteriorhodopsin and Retinal Chromophores and Their Applications for Optical Information Storage and Processing.

    NASA Astrophysics Data System (ADS)

    Chen, Zhongping

    Retinal, a conjugated polyene, plays a crucial role in biology. Both the visual pigments and the energy transducing protein, bacteriorhodopsin (BR) have a form of retinal as their chromophores. Because visual excitation and energy transduction in these systems is initiated by the promotion of retinal to an excited electronic state, information about the excited-state structure of retinal and the effect of chromophore/protein interactions on this structure are essential to understanding the functions of these systems. In this thesis, surface second harmonic (SH) generation is used to measure the light-induced dipole moment changes of a series of retinal derivatives that were designed and synthesized to model specific components of chromophore/protein interactions. In addition, we report an in situ probe of the dipole moment change of the retinal chromophore bound in BR by SH generation from oriented purple membranes. The dipole moment changes of various forms of BR, including light-adapted, dark-adapted, blue, and acid purple membrane, were measured and compared. These results, combined with the results from model compounds, elucidate the effects of the chromophore/protein interactions on light-induced charge redistribution and give insight on the fundamental nature of light excitation and energy storage in SR and rhodopsin. Furthermore, the dependence of the molecular hyperpolarizability of the conjugated molecules on donor/acceptor strength, protonation, conjugate length, planarity, and nonconjugate charges is investigated. Our study shows for the first time that nonconjugated charges have a very large effect on the nonlinear optical properties of conjugated molecules. BR has interesting photochromic characteristics, very large optical nonlinearities, and a unique optoelectrical property where the polarity of the photovoltage depends on both its photochromic state and the excitation wavelength. These unique characteristics coupled with its high stability make BR

  9. Progress in High-Capacity Core-Shell Cathode Materials for Rechargeable Lithium Batteries.

    PubMed

    Myung, Seung-Taek; Noh, Hyung-Joo; Yoon, Sung-June; Lee, Eung-Ju; Sun, Yang-Kook

    2014-02-20

    High-energy-density rechargeable batteries are needed to fulfill various demands such as self-monitoring analysis and reporting technology (SMART) devices, energy storage systems, and (hybrid) electric vehicles. As a result, high-energy electrode materials enabling a long cycle life and reliable safety need to be developed. To ensure these requirements, new material chemistries can be derived from combinations of at least two compounds in a secondary particle with varying chemical composition and primary particle morphologies having a core-shell structure and spherical cathode-active materials, specifically a nanoparticle core and shell, nanoparticle core and nanorod shell, and nanorod core and shell. To this end, several layer core-shell cathode materials were developed to ensure high capacity, reliability, and safety. PMID:26270835

  10. Storage density estimation for the phase-encoding and shift multiplexing holographic optical correlator

    NASA Astrophysics Data System (ADS)

    Zheng, Tianxiang; Cao, Liangcai; He, Qingsheng; Jin, Guofan

    2013-09-01

    Holographic optical correlator (HOC) is applicable in occasion where the instant search throughout a huge database is demanded. The primary advantage of the HOC is its inherent parallel processing ability and large storage capacity. The HOC's searching speed is proportional to the storage density. This paper proposes a phase-encoding method in the object beam to increase the storage density. A random phase plate (RPP) is used to encode the phase of the object beam before uploading the data pages to the object beam. By shifting the RPP at a designed interval, the object beam is modulated into an orthogonal object beam to the previous one and a new group of database can be stored. Experimental results verify the proposed method. The maximum storage number of the data pages with a RPP at a fixed position can be as large as 7,500. The crosstalk among different groups of the databases can be unnoticeable. The increase in the storage density of the HOC depends on the number of the orthogonal positions from the different portions of a same RPP.

  11. Ultra-high density optical data storage in common transparent plastics

    NASA Astrophysics Data System (ADS)

    Kallepalli, Deepak L. N.; Alshehri, Ali M.; Marquez, Daniela T.; Andrzejewski, Lukasz; Scaiano, Juan C.; Bhardwaj, Ravi

    2016-05-01

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc.

  12. Ultra-high density optical data storage in common transparent plastics.

    PubMed

    Kallepalli, Deepak L N; Alshehri, Ali M; Marquez, Daniela T; Andrzejewski, Lukasz; Scaiano, Juan C; Bhardwaj, Ravi

    2016-01-01

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc. PMID:27221758

  13. Ultra-high density optical data storage in common transparent plastics

    PubMed Central

    Kallepalli, Deepak L. N.; Alshehri, Ali M.; Marquez, Daniela T.; Andrzejewski, Lukasz; Scaiano, Juan C.; Bhardwaj, Ravi

    2016-01-01

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc. PMID:27221758

  14. LIGHT SOURCE: Optics for the lattice of the compact storage ring for a Compton X-ray source

    NASA Astrophysics Data System (ADS)

    Yu, Pei-Cheng; Wang, Yu; Shen, Xiao-Zhe; Huang, Wen-Hui; Yan, Li-Xin; Du, Ying-Chao; Li, Ren-Kai; Tang, Chuan-Xiang

    2009-06-01

    We present two types of optics for the lattice of a compact storage ring for a Compton X-ray source. The optics design for different operation modes of the storage ring are discussed in detail. For the pulse mode optics, an IBS-suppression scheme is applied to optimize the optics for lower IBS emittance growth rate; as for the steady mode, the method to control momentum compact factor is adopted [Gladkikh P, Phys. Rev. ST Accel. Beams 8, 050702] to obtain stability of the electron beam.

  15. Ensuring long-term reliability of the data storage on optical disc

    NASA Astrophysics Data System (ADS)

    Chen, Ken; Pan, Longfa; Xu, Bin; Liu, Wei

    2008-12-01

    "Quality requirements and handling regulation of archival optical disc for electronic records filing" is released by The State Archives Administration of the People's Republic of China (SAAC) on its network in March 2007. This document established a complete operative managing process for optical disc data storage in archives departments. The quality requirements of the optical disc used in archives departments are stipulated. Quality check of the recorded disc before filing is considered to be necessary and the threshold of the parameter of the qualified filing disc is set down. The handling regulations for the staffs in the archives departments are described. Recommended environment conditions of the disc preservation, recording, accessing and testing are presented. The block error rate of the disc is selected as main monitoring parameter of the lifetime of the filing disc and three classes pre-alarm lines are created for marking of different quality check intervals. The strategy of monitoring the variation of the error rate curve of the filing discs and moving the data to a new disc or a new media when the error rate of the disc reaches the third class pre-alarm line will effectively guarantee the data migration before permanent loss. Only when every step of the procedure is strictly implemented, it is believed that long-term reliability of the data storage on optical disc for archives departments can be effectively ensured.

  16. New optical architecture for holographic data storage system compatible with Blu-ray Disc™ system

    NASA Astrophysics Data System (ADS)

    Shimada, Ken-ichi; Ide, Tatsuro; Shimano, Takeshi; Anderson, Ken; Curtis, Kevin

    2014-02-01

    A new optical architecture for holographic data storage system which is compatible with a Blu-ray Disc™ (BD) system is proposed. In the architecture, both signal and reference beams pass through a single objective lens with numerical aperture (NA) 0.85 for realizing angularly multiplexed recording. The geometry of the architecture brings a high affinity with an optical architecture in the BD system because the objective lens can be placed parallel to a holographic medium. Through the comparison of experimental results with theory, the validity of the optical architecture was verified and demonstrated that the conventional objective lens motion technique in the BD system is available for angularly multiplexed recording. The test-bed composed of a blue laser system and an objective lens of the NA 0.85 was designed. The feasibility of its compatibility with BD is examined through the designed test-bed.

  17. Ultrathin reduced graphene oxide films for high performance optical data storage

    NASA Astrophysics Data System (ADS)

    Xing, Fei; Yang, Yong; Zhu, Siwei; Yuan, Xiaocong

    2015-10-01

    Optical data storage (ODS) represents revolutionary progress for the field of information storage capacity. When the thickness of data recording layer is similar to a few nanometer even atomic scale, the data point dimension can decrease to the minimum with stable mechanical property. Thus the new generation of ODS requires data recording layer in nanoscale to improve areal storage density, so that the more digital information can be stored in limited zone. Graphene, a novel two-dimensional (2D) material, is a type of monolayer laminated structure composed of carbon atoms and is currently the thinnest known material (the thickness of monolayer graphene is 3.35 Å). It is an ideal choice as a active layer for ODS media. Reduced graphene oxide, a graphene derivative, has outstanding polarization-dependent absorption characteristics under total internal reflection (TIR). The strong broadband absorption of reduced graphene oxide causes it to exhibit different reflectance for transverse electric (TE) and transverse magnetic (TM) modes under TIR, and the maximum reflectance ratio between TM and TE modes is close to 8 with 8 nm reduced graphene oxide films. It opens a door for a high signal to noise ratio (SNR) graphene-based optical data storage. Here, 8 nm high-temperature reduced graphene oxide (h-rGO) films was used for the ultrathin active layer of ODS. The data writing was performed on the h-rGO active layer based on photolithography technology. Under TIR, a balanced detection technology in the experiment converts the optical signals into electric signals and simultaneously amplifies them. The reading results show a stable SNR up to 500, and the graphene-based ODS medium has a high transparency performance.

  18. From the surface to volume: concepts for the next generation of optical-holographic data-storage materials.

    PubMed

    Bruder, Friedrich-Karl; Hagen, Rainer; Rölle, Thomas; Weiser, Marc-Stephan; Fäcke, Thomas

    2011-05-01

    Optical data storage has had a major impact on daily life since its introduction to the market in 1982. Compact discs (CDs), digital versatile discs (DVDs), and Blu-ray discs (BDs) are universal data-storage formats with the advantage that the reading and writing of the digital data does not require contact and is therefore wear-free. These formats allow convenient and fast data access, high transfer rates, and electricity-free data storage with low overall archiving costs. The driving force for development in this area is the constant need for increased data-storage capacity and transfer rate. The use of holographic principles for optical data storage is an elegant way to increase the storage capacity and the transfer rate, because by this technique the data can be stored in the volume of the storage material and, moreover, it can be optically processed in parallel. This Review describes the fundamental requirements for holographic data-storage materials and compares the general concepts for the materials used. An overview of the performance of current read-write devices shows how far holographic data storage has already been developed. PMID:21538730

  19. Organotrisulfide: A High Capacity Cathode Material for Rechargeable Lithium Batteries.

    PubMed

    Wu, Min; Cui, Yi; Bhargav, Amruth; Losovyj, Yaroslav; Siegel, Amanda; Agarwal, Mangilal; Ma, Ying; Fu, Yongzhu

    2016-08-16

    An organotrisulfide (RSSSR, R is an organic group) has three sulfur atoms which could be involved in multi-electron reduction reactions; therefore it is a promising electrode material for batteries. Herein, we use dimethyl trisulfide (DMTS) as a model compound to study its redox reactions in rechargeable lithium batteries. With the aid of XRD, XPS, and GC-MS analysis, we confirm DMTS could undergo almost a 4 e(-) reduction process in a complete discharge to 1.0 V. The discharge products are primarily LiSCH3 and Li2 S. The lithium cell with DMTS catholyte delivers an initial specific capacity of 720 mAh g(-1) DMTS and retains 82 % of the capacity over 50 cycles at C/10 rate. When the electrolyte/DMTS ratio is 3:1 mL g(-1) , the reversible specific energy for the cell including electrolyte can be 229 Wh kg(-1) . This study shows organotrisulfide is a promising high-capacity cathode material for high-energy rechargeable lithium batteries. PMID:27411083

  20. High-capacity quantum Fibonacci coding for key distribution

    NASA Astrophysics Data System (ADS)

    Simon, David S.; Lawrence, Nate; Trevino, Jacob; Dal Negro, Luca; Sergienko, Alexander V.

    2013-03-01

    Quantum cryptography and quantum key distribution (QKD) have been the most successful applications of quantum information processing, highlighting the unique capability of quantum mechanics, through the no-cloning theorem, to securely share encryption keys between two parties. Here, we present an approach to high-capacity, high-efficiency QKD by exploiting cross-disciplinary ideas from quantum information theory and the theory of light scattering of aperiodic photonic media. We propose a unique type of entangled-photon source, as well as a physical mechanism for efficiently sharing keys. The key-sharing protocol combines entanglement with the mathematical properties of a recursive sequence to allow a realization of the physical conditions necessary for implementation of the no-cloning principle for QKD, while the source produces entangled photons whose orbital angular momenta (OAM) are in a superposition of Fibonacci numbers. The source is used to implement a particular physical realization of the protocol by randomly encoding the Fibonacci sequence onto entangled OAM states, allowing secure generation of long keys from few photons. Unlike in polarization-based protocols, reference frame alignment is unnecessary, while the required experimental setup is simpler than other OAM-based protocols capable of achieving the same capacity and its complexity grows less rapidly with increasing range of OAM used.

  1. Tracking inhomogeneity in high-capacity lithium iron phosphate batteries

    NASA Astrophysics Data System (ADS)

    Paxton, William A.; Zhong, Zhong; Tsakalakos, Thomas

    2015-02-01

    Energy-dispersive x-ray diffraction (EDXRD) is one of the few techniques that can internally probe a sealed battery under operating conditions. In this paper, we use EDXRD with ultrahigh energy synchrotron radiation to track inhomogeneity in a cycled high-capacity lithium iron phosphate cell under in-situ and operando conditions. A sequence of depth-profile x-ray diffraction spectra are collected with 40 μm resolution as the cell is discharged. Additionally, nine different locations of the cell are tracked independently throughout a second discharge process. In each case, a two-peak reference intensity ratio analysis (RIR) was used on the LiFePO4 311 and the FePO4 020 reflections to estimate the relative phase abundance of the lithiated and non-lithiated phases. The data provide a first-time look at the dynamics of electrochemical inhomogeneity in a real-world battery. We observe a strong correlation between inhomogeneity and overpotential in the galvanic response of the cell. Additionally, the data closely follow the behavior that is predicted by the resistive-reactant model originally proposed by Thomas-Alyea. Despite a non-linear response in the independently measured locations, the behavior of the ensemble is strikingly linear. This suggests that effects of inhomogeneity can be elusive and highlights the power of the EDXRD technique.

  2. High capacity color barcodes using dot orientation and color separability

    NASA Astrophysics Data System (ADS)

    Bulan, Orhan; Monga, Vishal; Sharma, Gaurav

    2009-02-01

    Barcodes are widely utilized for embedding data in printed format to provide automated identification and tracking capabilities in a number of applications. In these applications, it is desirable to maximize the number of bits embedded per unit print area in order to either reduce the area requirements of the barcodes or to offer an increased payload, which in turn enlarges the class of applications for these barcodes. In this paper, we present a new high capacity color barcode. Our method operates by embedding independent data in two different printer colorant channels via halftone-dot orientation modulation. In the print, the dots of the two colorants occupy the same spatial region. At the detector, however, by using the complementary sensor channels to estimate the colorant channels we can recover the data in each individual colorant channel. The method therefore (approximately) doubles the capacity of encoding methods based on a single colorant channel and provides an embedding rate that is higher than other known barcode alternatives. The effectiveness of the proposed technique is demonstrated by experiments conducted on Xerographic printers. Data embedded at a high density by using the two cyan and yellow colorant channels for halftone dot orientation modulation is successfully recovered by using the red and blue channels for the detection, with an overall symbol error rate that is quite small.

  3. Demonstration of a high-capacity turboalternator for a 20 K, 20 W space-borne Brayton cryocooler

    NASA Astrophysics Data System (ADS)

    Zagarola, M.; Cragin, K.; Deserranno, D.

    2014-01-01

    NASA is considering multiple missions involving long-term cryogenic propellant storage in space. Liquid hydrogen and oxygen are the typical cryogens as they provide the highest specific impulse of practical chemical propellants. Storage temperatures are nominally 20 K for liquid hydrogen and 90 K for liquid oxygen. Heat loads greater than 10 W at 20 K are predicted for hydrogen storage. Current space cryocoolers have been developed for sensor cooling with refrigeration capacities less than 1 W at 20 K. In 2011, Creare Inc. demonstrated an ultra-low-capacity turboalternator for use in a turbo-Brayton cryocooler. The turboalternator produced up to 5 W of turbine refrigeration at 20 K; equivalent to approximately 3 W of net cryocooler refrigeration. This turboalternator obtained unprecedented operating speeds and efficiencies at low temperatures benefitting from new rotor design and fabrication techniques, and new bearing fabrication techniques. More recently, Creare applied these design and fabrication techniques to a larger and higher capacity 20 K turboalternator. The turboalternator was tested in a high-capacity, low temperature test facility at Creare and demonstrated up to 42 W of turbine refrigeration at 20 K; equivalent to approximately 30 W of net cryocooler refrigeration. The net turbine efficiency was the highest achieved to date at Creare for a space-borne turboalternator. This demonstration was the first step in the development of a high-capacity turbo-Brayton cryocooler for liquid hydrogen storage. In this paper, we will review the design, development and testing of the turboalternator.

  4. Photon storage in {lambda}-type optically dense atomic media. III. Effects of inhomogeneous broadening

    SciTech Connect

    Gorshkov, Alexey V.; Andre, Axel; Lukin, Mikhail D.; Soerensen, Anders S.

    2007-09-15

    In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)] and in the two preceding papers [Gorshkov et al., this issue, Phys. Rev. A 76, 033804 (2006); 76, 033805 (2006)], we used a universal physical picture to optimize and demonstrate equivalence between a wide range of techniques for storage and retrieval of photon wave packets in homogeneously broadened {lambda}-type atomic media, including the adiabatic reduction of the photon group velocity, pulse-propagation control via off-resonant Raman techniques, and photon-echo-based techniques. In the present paper, we generalize this treatment to include inhomogeneous broadening. In particular, we consider the case of Doppler-broadened atoms and assume that there is a negligible difference between the Doppler shifts of the two optical transitions. In this situation, we show that, at high enough optical depth, all atoms contribute coherently to the storage process as if the medium were homogeneously broadened. We also discuss the effects of inhomogeneous broadening in solid state samples. In this context, we discuss the advantages and limitations of reversing the inhomogeneous broadening during the storage time, as well as suggest a way for achieving high efficiencies with a nonreversible inhomogeneous profile.

  5. Polarization multiplexed write-once-read-many optical data storage in bacteriorhodopsin films.

    PubMed

    Yao, Baoli; Lei, Ming; Ren, Liyong; Menke, Neimule; Wang, Yingli; Fischer, Thorsten; Hampp, Norbert

    2005-11-15

    In polymeric films of bacteriorhodopsin (BR) a photoconversion product, which was named the F620 state, was observed on excitation of the film with 532 nm nanosecond laser pulses. This photoproduct shows a strong nonlinear absorption. Such BR films can be used for write-once-read-many (WORM) optical data storage. We demonstrate that a photoproduct similar or even identical to that obtained with nanosecond pulses is generated on excitation with 532 nm femtosecond pulses. This photoproduct also shows strong anisotropic absorption, which facilitates polarization storage of data. The product is thermally stable and is irretrievable to the initial B state either by photochemical reaction or through a thermal pathway. The experimental results indicate that the product is formed by a two-photon absorption process. Optical WORM storage is demonstrated by use of two polarization states, but more polarization states may be used. The combination of polarization data multiplexing and extremely short recording time in the femtosecond range enables very high data volumes to be stored within a very short time. PMID:16315721

  6. Polarization multiplexed write-once-read-many optical data storage in bacteriorhodopsin films

    NASA Astrophysics Data System (ADS)

    Yao, Baoli; Lei, Ming; Ren, Liyong; Menke, Neimule; Wang, Yingli; Fischer, Thorsten; Hampp, Norbert

    2005-11-01

    In polymeric films of bacteriorhodopsin (BR) a photoconversion product, which was named the F620 state, was observed on excitation of the film with 532 nm nanosecond laser pulses. This photoproduct shows a strong nonlinear absorption. Such BR films can be used for write-once-read-many (WORM) optical data storage. We demonstrate that a photoproduct similar or even identical to that obtained with nanosecond pulses is generated on excitation with 532 nm femtosecond pulses. This photoproduct also shows strong anisotropic absorption, which facilitates polarization storage of data. The product is thermally stable and is irretrievable to the initial B state either by photochemical reaction or through a thermal pathway. The experimental results indicate that the product is formed by a two-photon absorption process. Optical WORM storage is demonstrated by use of two polarization states, but more polarization states may be used. The combination of polarization data multiplexing and extremely short recording time in the femtosecond range enables very high data volumes to be stored within a very short time.

  7. Inspection of commercial optical devices for data storage using a three Gaussian beam microscope interferometer

    SciTech Connect

    Flores, J. Mauricio; Cywiak, Moises; Servin, Manuel; Juarez P, Lorenzo

    2008-09-20

    Recently, an interferometric profilometer based on the heterodyning of three Gaussian beams has been reported. This microscope interferometer, called a three Gaussian beam interferometer, has been used to profile high quality optical surfaces that exhibit constant reflectivity with high vertical resolution and lateral resolution near {lambda}. We report the use of this interferometer to measure the profiles of two commercially available optical surfaces for data storage, namely, the compact disk (CD-R) and the digital versatile disk (DVD-R). We include experimental results from a one-dimensional radial scan of these devices without data marks. The measurements are taken by placing the devices with the polycarbonate surface facing the probe beam of the interferometer. This microscope interferometer is unique when compared with other optical measuring instruments because it uses narrowband detection, filters out undesirable noisy signals, and because the amplitude of the output voltage signal is basically proportional to the local vertical height of the surface under test, thus detecting with high sensitivity. We show that the resulting profiles, measured with this interferometer across the polycarbonate layer, provide valuable information about the track profiles, making this interferometer a suitable tool for quality control of surface storage devices.

  8. Optimization of the permanent magnet optical klystron for the SUPER-ACO storage ring free electron laser

    NASA Astrophysics Data System (ADS)

    Couprie, M. E.; Bazin, C.; Billardon, M.

    1989-06-01

    A permanent magnet optical klystron has been optimized for free electron laser experiments and optical harmonic generation on the new storage ring SUPER-ACO at Orsay. The conditions of the optimization and the different steps of the field characterization measurements of this insertion device are discussed. Its effects on the stored beam and the undulator radiation measurements are described.

  9. Phase-to-amplitude data page conversion for holographic storage and optical encryption.

    PubMed

    Koppa, Pál

    2007-06-10

    A new phase-to-amplitude data page conversion method is proposed for efficient recovery of the data encoded in phase-modulated data pages used in holographic storage and optical encryption. The method is based on the interference between the data page and its copy shifted by an integral number of pixels. Key properties such as Fourier plane homogeneity, bit error rate, and positioning tolerances are investigated by computer modeling, and a comparison is provided with amplitude-modulated data page holographic storage with and without static phase masks. The feasibility and the basic properties of the proposed method are experimentally demonstrated. The results show that phase-modulated data pages can be used efficiently with reduced system complexity. PMID:17514316

  10. A high-capacity streptavidin-coated microtitration plate.

    PubMed

    Välimaa, Lasse; Pettersson, Kim; Vehniäinen, Markus; Karp, Matti; Lövgren, Timo

    2003-01-01

    A majority of current immunoassays rely on capturing a specific analyte on a solid phase to allow the separation of the bound analyte from nonbound components. Streptavidin-coated microtitration plates are widely used for immobilization of capturing antibodies, since they provide a generic surface for immobilization of any biotinylated molecule and preserve biomolecule activity much better than direct passive adsorption. Our trials to further improve the properties of the plates resulted in a development of a modified plate, which has higher binding capacity than currently used control plate. The modified coat was prepared by cross-linking streptavidin chemically prior to adsorption onto the microtitration well surfaces. The binding capacities of the plates were measured with biotinylated, europium-labeled molecules and labeled antigen. The immunoassay performance of the plates was studied with noncompetitive, sandwich-type assays of prostate specific antigen (PSA) and human chorionic gonadotropin (hCG). The maximum immobilization capacity of the modified plate was up to 2.5 times higher than that of the control plate. The higher binding capacity was especially emphasized with small-size molecules. The modified high capacity plate increased the linear ranges of the immunoassays and thus delayed the high-dose hook effect. At high antigen concentrations the signal increased up to 59%, and at the conventional linear ranges of the assays, the increase was up to 29%. We conclude that the modified coating method will be valuable for the future miniaturized systems, where high immobilization capacity is needed at limited areas. PMID:12526699

  11. Experimental study of the dependences of retrieval efficiencies on time delay between magneto-optical-trap being turned off and optical storage

    NASA Astrophysics Data System (ADS)

    Li-Rong, Chen; Zhong-Xiao, Xu; Ping, Li; Ya-Fei, Wen; Wei-Qing, Zeng; Yue-Long, Wu; Long, Tian; Shu-Jing, Li; Hai, Wang

    2016-02-01

    We report an experimental study of electromagnetically induced transparency (EIT)-based light storage in a cloud of cold atoms loaded into a magneto-optical-trap (MOT). After the MOT is turned off, the retrieval efficiencies of right- and left-circularly polarized signal light fields each as a function of storage time are measured for different time delays between MOT off and the storage event, respectively. The results show that in the delay ranging from 0.015 ms to 3.5 ms, the retrieval efficiency for a zero-storage time (0.2 μs) and the storage lifetime can exceed 15% and 1.4 ms, respectively. The measured results will provide important help for optimizing the storage of the polarized entanglement photons in cold atomic ensembles. Project supported by the National Basic Research Program of China (Grant No. 2010CB923103) and the National Natural Science Foundation of China (Grant Nos. 11475109, 11274211, and 60821004).

  12. Optical noise reduction for dc-removed coaxial holographic data storage.

    PubMed

    Yasuda, Shin; Minabe, Jiro; Kawano, Katsunori

    2007-01-15

    A method of reconstructing positive and negative images from Fourier holograms recorded without the dc components is demonstrated by use of a coaxial holographic storage system. Reconstructed images are obtained by adding a phase-modulated dc component of the signal beam on reading. Contrast reversal of the reconstructed images can be achieved by reversing the readout reference pattern. This method can realize not only optical noise reduction but also less consumption of the dynamic range of the recording medium, potentially contributing to increasing the number of multiplexed holograms. PMID:17186050

  13. Optical memory development. Volume 2: Gain-assisted holographic storage media

    NASA Technical Reports Server (NTRS)

    Gange, R. A.; Mezrich, R. S.

    1972-01-01

    Thin deformable films were investigated for use as the storage medium in a holographic optical memory. The research was directed toward solving the problems of material fatigue, selective heat addressing, electrical charging of the film surface and charge patterning by light. A number of solutions to these problems were found but the main conclusion to be drawn from the work is that deformable media which employ heat in the recording process are not satisfactory for use in a high-speed random-access read/write holographic memory. They are, however, a viable approach in applications where either high speed or random-access is not required.

  14. Rapid production of structural color images with optical data storage capabilities

    NASA Astrophysics Data System (ADS)

    Rezaei, Mohamad; Jiang, Hao; Qarehbaghi, Reza; Naghshineh, Mohammad; Kaminska, Bozena

    2015-03-01

    In this paper, we present novel methods to produce structural color image for any given color picture using a pixelated generic stamp named nanosubstrate. The nanosubstrate is composed of prefabricated arrays of red, green and blue subpixels. Each subpixel has nano-gratings and/or sub-wavelength structures which give structural colors through light diffraction. Micro-patterning techniques were implemented to produce the color images from the nanosubstrate by selective activation of subpixels. The nano-grating structures can be nanohole arrays, which after replication are converted to nanopillar arrays or vice versa. It has been demonstrated that visible and invisible data can be easily stored using these fabrication methods and the information can be easily read. Therefore the techniques can be employed to produce personalized and customized color images for applications in optical document security and publicity, and can also be complemented by combined optical data storage capabilities.

  15. Surface-micromachined optical polarizers for magneto-optical data storage

    NASA Astrophysics Data System (ADS)

    Pu, Chuan; Zhu, Zuhua; Lo, Yu-Hwa

    1998-07-01

    Polarizers and polarization beam splitters are the most important devices in magneto-optical readout system. With a commercially available foundry polysilicon surface micromachining process (Multi-User Means ProcesS, or MUMPS) offered by MCNC (Mems Center at North Carolina), we have realized, on a single Si chip, an integrated polarization beam splitting system with a binary phase Fresnel lens for collimation. Polarization extinction ratios of 10 dB for the transmitted light and over 20 dB for the reflected light have been achieved. The whole system is prealigned using Computer-Aided Design on a Si substrate and is then lifted up perpendicular to the substrate after structure release.

  16. Thermoelectric PbTe thin film for superresolution optical data storage

    SciTech Connect

    Lee, Hyun Seok; Cheong, Byung-ki; Lee, Taek Sung; Lee, Kyeong Seok; Kim, Won Mok; Lee, Jae Won; Cho, Sung Ho; Youl Huh, Joo

    2004-10-04

    To find its practical use in ultrahigh density optical data storage, superresolution (SR) technique needs a material that can render a high SR capability at no cost of durability against repeated readout and write. Thermoelectric materials appear to be promising candidates due to their capability of yielding phase-change-free thermo-optic changes. A feasibility study was carried out with PbTe for its large thermoelectric coefficient and high stability over a wide temperature range as a crystalline single phase. Under exposure to pulsed red light, the material was found to display positive, yet completely reversible changes of optical transmittance regardless of laser power, fulfilling basic requirements for SR readout and write. The material was also shown to have a high endurance against repeated static laser heating of up to 10{sup 6}-10{sup 7} cycles tested. A read only memory disk with a PbTe SR layer led to the carrier to noise ratio value of 47 dB at 3.5 mW for 0.25 {mu}m pit; below the optical resolution limit ({approx}0.27 {mu}m) of the tester.

  17. Soliton Solutions for High-Bandwidth Optical Pulse Storage and Retrieval

    NASA Astrophysics Data System (ADS)

    Groves, Elizabeth

    Quantum-optical information processing in material systems requires on-demand manipulation and precision control techniques. Previous implementations of optical pulse control have mostly been limited to weak, narrowband probe fields, often using a modified form of Electromagnetically Induced Transparency (EIT). We propose optical pulse control in a contrasting regime with high-bandwidth optical pulses, enabling higher clock-rates and on-demand fast pulse switching. Our novel solutions exploit the coherent interaction between short, strong pulses and resonant media (such as a cloud of ultra-cold atoms) to store, manipulate, and retrieve high-bandwidth optical pulse information. The evolution equations that model such short pulse propagation are inherently nonlinear and they govern both amplitudes and phases of the propagating field and the dielectric medium. They cannot be modeled by population rate equations or simplified with steady-state assumptions. Nonlinear evolution equations do not yield solutions easily and using them to characterize the physics at hand typically requires complementary analytical and numerical approaches. We take both approaches here, using analytical methods and our own numerical integration code. For uniform and infinitely extended media we generate novel three-pulse soliton solutions: robust, nonlinear waves with the unique property of preserving their shape under interaction (or "collision"). This important property enables one high-bandwidth soliton to push another from one location in an atomic cloud to another, predictably and nondestructively. We then also probe the practical utility of our specialized infinite-extent solutions by numerically solving the same nonlinear evolution equations for a variety of initial pulse shapes and strengths. Our numerical simulations confirm that our novel soliton solutions provide appropriate control parameters, including pulse storage locations and pulse sequencing, even in finite media under non

  18. High-capacity content-addressable memory architecture

    NASA Astrophysics Data System (ADS)

    Henshaw, Philip D.; Lis, Steven A.

    1993-11-01

    This paper describes a new hardware architecture for searching and accessing data. This Content Addressable Memory (CAM) can be implemented using holographic storage in spectral hole burning media. The use of laser wavelength as a fourth dimension for volume holographic recording provides an additional addressing variable which can be used to advantage in a CAM architecture. This paper consists of three parts: definition of a CAM, presentation of two CAM concepts for digital data string and analog function search, and a discussion of architecture issues.

  19. Halbach-Magnet-Array-Based Focusing Actuator for Small-Form-Factor Optical Storage Device

    NASA Astrophysics Data System (ADS)

    Lee, Sung‑Q; Park, Kang‑Ho; Paek, Mun‑Cheal; Kang, Kwang‑Yong

    2006-02-01

    Small-form-factor optical data storage devices are being developed rapidly nowadays. In the case of a CF-II-type optical data storage device (43×36×5 mm3), its components such as the disk, head, focusing actuator, and spindle motor should be assembled within a 5 mm thickness. Since the thickness specification is tight, each component should be designed to have a small thickness. In this paper, a Halbach magnet array is proposed for the focusing actuator. The proposed Halbach magnet array has the advantage of a thin actuation structure without sacrificing flux densities due to its special magnet array feature that increases the magnetic flux on one side without using a yoke. By finite element method (FEM) analysis, flux density, actuation force and actuator thickness are compared with those of conventional methods. Each dimension of the array is obtained to achieve higher performances. Finally, the working range and the resolution of the focusing actuator are experimentally obtained to verify the feasibility of the proposed idea.

  20. O/E/O storage mechanism for burst contention resolution in optical burst switching networks

    NASA Astrophysics Data System (ADS)

    Sun, Yutong; Zheng, Xiaoping; Zhang, Hanyi; Pu, Tao; Wang, Lei; Guo, Yili

    2005-11-01

    Burst contention resolution is one of the most important issues in optical burst switching (OBS) networks. In this paper, an O/E/O conversion and electronic storage mechanism for contention resolution is proposed. Compared with fiber delay lines (FDL) O/E/O strategy can provide much longer and continuous delay time for the contending bursts, which can significantly reduce burst loss rate. For this mechanism, a new burst scheduling algorithm called Shortest Delay- Best Fit (SD-BF) is proposed here to improve bandwidth utilization. In a network, O/E/O can be implemented with FDL to achieve a better performance while reducing node cost. In this paper, a semi-share structure for this combination strategy is proposed to balance the cost and performance. Numerical results show that a better performance is achieved by the combination strategy in the long haul back-bone networks. We also investigate the maximum electronic RAM capacity needed in the nodes to support O/E/O storage, and how to implement Quality-of-Service (QoS) with O/E/O storage.

  1. Technology goals for high-capacity communications satellites

    NASA Astrophysics Data System (ADS)

    Welti, G. R.

    1982-09-01

    Assuming certain traffic and earth station characteristics, three satellite system architectures are developed in order to define desirable interface and performance goals for satellite processing technology development. Architecture I employs 6/4 and 14/11 GHz bands with baseband processing; architecture II adds the use of the 30/20 GHz band to those above; architecture III uses all three pairs of bands without baseband processing. It is shown that full exploitation of the 14/11 GHz band with wideband transponders permits mass reductions in the antenna subsystem and power reductions in the baseband processor. Technological improvement is suggested for on-board switching of the baseband, 4 GHz, and 11 GHz, for on-board modulators and demodulators of 4 GHz and 11 GHz, and for on-board buffer storage elements.

  2. Porous graphene for high capacity lithium ion battery anode material

    NASA Astrophysics Data System (ADS)

    Wang, Yusheng; Zhang, Qiaoli; Jia, Min; Yang, Dapeng; Wang, Jianjun; Li, Meng; Zhang, Jing; Sun, Qiang; Jia, Yu

    2016-02-01

    Based on density functional theory calculations, we studied the Li dispersed on porous graphene (PG) for its application as Li ion battery anode material. The hybridization of Li atoms and the carbon atoms enhanced the interaction between Li atoms and the PG. With holes of specific size, the PG can provide excellent mobility with moderate barriers of 0.37-0.39 eV. The highest Li storage composite can be LiC0.75H0.38 which corresponds to a specific capacity of 2857.7 mA h/g. Both specific capacity and binding energy are significantly larger than the corresponding value of graphite, this makes PG a promising candidate for the anode material in battery applications. The interactions between the Li atoms and PG can be easily tuned by an applied strain. Under biaxial strain of 16%, the binding energy of Li to PG is increased by 17% compared to its unstrained state.

  3. Acoustic emission detection with fiber optical sensors for dry cask storage health monitoring

    NASA Astrophysics Data System (ADS)

    Lin, Bin; Bao, Jingjing; Yu, Lingyu; Giurgiutiu, Victor

    2016-04-01

    The increasing number, size, and complexity of nuclear facilities deployed worldwide are increasing the need to maintain readiness and develop innovative sensing materials to monitor important to safety structures (ITS). In the past two decades, an extensive sensor technology development has been used for structural health monitoring (SHM). Technologies for the diagnosis and prognosis of a nuclear system, such as dry cask storage system (DCSS), can improve verification of the health of the structure that can eventually reduce the likelihood of inadvertently failure of a component. Fiber optical sensors have emerged as one of the major SHM technologies developed particularly for temperature and strain measurements. This paper presents the development of optical equipment that is suitable for ultrasonic guided wave detection for active SHM in the MHz range. An experimental study of using fiber Bragg grating (FBG) as acoustic emission (AE) sensors was performed on steel blocks. FBG have the advantage of being durable, lightweight, and easily embeddable into composite structures as well as being immune to electromagnetic interference and optically multiplexed. The temperature effect on the FBG sensors was also studied. A multi-channel FBG system was developed and compared with piezoelectric based AE system. The paper ends with conclusions and suggestions for further work.

  4. New interleaving scheme for error correction code of a multilevel optical storage system

    NASA Astrophysics Data System (ADS)

    Liu, Hailong; Pan, Longfa; Hu, Beibei; Liu, Xiangwei

    2008-12-01

    Disc scratches, dusts and noise corruption et al. will cause data sequence errors including random errors and burst errors. With the recording density of multilevel (ML) optical storage system increasing, the same length of scratches on the surface of optical disc will bring more burst errors in ML DVD than conventional optical recording systems, e.g., digital versatile disc (DVD) and compact disc (CD). A new interleaving scheme based on Reed-Solomon code (RS) is proposed to solve this problem. In DVD system, the burden of the Parity of Outer-code (PO) is huge, while the Parity of Innercode (PI) has more correcting ability than needed. The new interleaving algorithm adjusts the structure of data frame and block and improves the interleaving depth of ECC block to reduce the burden of PO. The results of numerical simulations are presented to verify the performance of the new interleaving algorithm compared with RSPC. The new proposed scheme can correct maximum burst error length of the proposed code is 6912 bytes. Burst error correcting capacity of the proposed scheme is improved up to137.4% more than that of the RSPC.

  5. Optoenergy storage, stimulated processes in optical amplification with electro-optic ceramic gain media of Nd3+ doped lanthanum lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Wu, Ye; Zhao, Hua; Zou, Yingyin K.; Chen, Xuesheng; Bartolo, Baldassare Di; Zhang, Jingwen W.

    2011-08-01

    Optical amplification was observed in electro-optic (EO) ceramic plates of neodymium doped lanthanum-modified lead zirconate titanate (Nd3+:PLZT), when the pumping and seeding beams are not overlapped temporarily. This striking feature in the gain measurement and the accompanying slowly trailing-off both seen in the optical amplification as well as in the lasing action are satisfactorily explained by electron releasing from the rich vacancy-based carrier traps in the intrinsically disordered ceramics, i.e., the consecutively optical, thermal stimuli are found responsible for the long persistent optoenergy storage, and consequently the slow response of the gain dynamics. These findings in optical amplification, the slowly trailing-off, and the underlying mechanism have opened a new way of developing novel controllable optical devices. The model thus established could serve as a guide in design and refinement of a new generation of products out of this excellent, well commercialized EO PLZT ceramics family and similar others.

  6. Enhanced Dissociation of Intact Proteins with High Capacity Electron Transfer Dissociation

    NASA Astrophysics Data System (ADS)

    Riley, Nicholas M.; Mullen, Christopher; Weisbrod, Chad R.; Sharma, Seema; Senko, Michael W.; Zabrouskov, Vlad; Westphall, Michael S.; Syka, John E. P.; Coon, Joshua J.

    2016-03-01

    Electron transfer dissociation (ETD) is a valuable tool for protein sequence analysis, especially for the fragmentation of intact proteins. However, low product ion signal-to-noise often requires some degree of signal averaging to achieve high quality MS/MS spectra of intact proteins. Here we describe a new implementation of ETD on the newest generation of quadrupole-Orbitrap-linear ion trap Tribrid, the Orbitrap Fusion Lumos, for improved product ion signal-to-noise via ETD reactions on larger precursor populations. In this new high precursor capacity ETD implementation, precursor cations are accumulated in the center section of the high pressure cell in the dual pressure linear ion trap prior to charge-sign independent trapping, rather than precursor ion sequestration in only the back section as is done for standard ETD. This new scheme increases the charge capacity of the precursor accumulation event, enabling storage of approximately 3-fold more precursor charges. High capacity ETD boosts the number of matching fragments identified in a single MS/MS event, reducing the need for spectral averaging. These improvements in intra-scan dynamic range via reaction of larger precursor populations, which have been previously demonstrated through custom modified hardware, are now available on a commercial platform, offering considerable benefits for intact protein analysis and top down proteomics. In this work, we characterize the advantages of high precursor capacity ETD through studies with myoglobin and carbonic anhydrase.

  7. Experiences and challenges running CERN's high capacity tape archive

    NASA Astrophysics Data System (ADS)

    Cancio, Germán; Bahyl, Vladimír; Kruse, Daniele Francesco; Leduc, Julien; Cano, Eric; Murray, Steven

    2015-12-01

    CERN's tape-based archive system has collected over 70 Petabytes of data during the first run of the LHC. The Long Shutdown is being used for migrating the complete 100 Petabytes data archive to higher-density tape media. During LHC Run 2, the archive will have to cope with yearly growth rates of up to 40-50 Petabytes. In this contribution, we describe the scalable setup for coping with the storage and long-term archival of such massive data amounts. We also review the challenges resulting and mechanisms devised for measuring and enhancing availability and reliability, as well as ensuring the long-term integrity and bit-level preservation of the complete data repository. The procedures and tools for the proactive and efficient operation of the tape infrastructure are described, including the features developed for automated problem detection, identification and notification. Finally, we present an outlook in terms of future capacity requirements growth and how it matches the expected tape technology evolution.

  8. Development of High Capacity Split Stirling Cryocooler for HTS

    NASA Astrophysics Data System (ADS)

    Yumoto, Kenta; Nakano, Kyosuke; Hiratsuka, Yoshikatsu

    Sumitomo Heavy Industries, Ltd. (SHI) developed a high-power Stirling-type pulse tube cryocooler for cooling high-temperature superconductor (HTS) devices, such as superconductor motors, superconducting magnetic energy storage (SMES), and fault current limiters. The experimental results of a prototype pulse tube cryocooler were reported in September 2013. For a U-type expander, the cooling capacity was 151 W at 70 K with a compressor input power of 4 kW. Correspondingly, the coefficient of performance (COP) was about 0.038. However, the efficiency of the cryocooler is required to be COP > 0.1 and it was found that, theoretically, it is difficult to further improve the efficiency of a pulse tube cryocooler because the workflow generated at the hot end of the pulse tube cannot be recovered. Therefore, it was decided to change the expander to a free-piston type from a pulse tube type. A prototype was developed and preliminary experiments were conducted. A cooling capacity of 120 W at 70 K with a compressor input power of 2.15 kW with corresponding COP of 0.056, was obtained. The detailed results are reported in this paper.

  9. Improving Recording Density of All-Optical Magnetic Storage by Using High-Pass Angular Spectrum Filters

    NASA Astrophysics Data System (ADS)

    Zhuang, You-Yi; Zhang, Yao-Ju

    2009-10-01

    A new design is presented to improve the magnetic recording density in all-optical magnetic storage. By using the high numerical lens with a high-pass angular spectrum filter, circularly polarized laser pulses are focused into the magneto-optic film with the perpendicular anisotropy. Magnetization of the film is induced by the inverse Faraday effect. As the obstructed angle of the filter increases the magnetic recording density increases evidently. The magnetization intensity and the sidelobe effect are also discussed.

  10. Systems Issues Pertaining to Holographic Optical Data Storage in Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Oezcan, Meric; Smithey, Daniel T.; Crew, Marshall; Lau, Sonie (Technical Monitor)

    1998-01-01

    The optical data storage capacity and raw bit-error-rate achievable with thick photochromic bacteriorhodopsin (BR) films are investigated for sequential recording and read- out of angularly- and shift-multiplexed digital holograms inside a thick blue-membrane D85N BR film. We address the determination of an exposure schedule that produces equal diffraction efficiencies among each of the multiplexed holograms. This exposure schedule is determined by numerical simulations of the holographic recording process within the BR material, and maximizes the total grating strength. We also experimentally measure the shift selectivity and compare the results to theoretical predictions. Finally, we evaluate the bit-error-rate of a single hologram, and of multiple holograms stored within the film.