WorldWideScience

Sample records for circuit switched optical

  1. Power consumption evaluation of circuit-switched versus packet-switched optical backbone networks

    OpenAIRE

    Van Heddeghem W.; Lannoo B.; Colle D.; Pickavet M.; Musumeci F.; Pattavina A.; Idzikowski F.

    2013-01-01

    While telecommunication networks have historically been dominated by a circuit-switched paradigm, the last decades have seen a clear trend towards packet-switched networks. In this paper we evaluate how both paradigms perform in optical backbone networks from a power consumption point of view, and whether the general agreement of circuit switching being more power-efficient holds. We consider artificially generated topologies of various sizes, mesh degrees and not yet previously explored in t...

  2. Resource allocation in circuit-switched all-optical networks

    Science.gov (United States)

    Marquis, Douglas; Barry, Richard A.; Finn, Steven G.; Parikh, Salil A.; Swanson, Eric A.; Thomas, Robert E.

    1996-03-01

    We describe an all-optical network testbed deployed in the Boston area, and research surrounding the allocation of optical resources -- frequencies and time slots -- within the network. The network was developed by a consortium of AT&T Bell Laboratories, Digital Equipment Corporation, and Massachusetts Institute of Technology under a grant from ARPA. The network is organized as a hierarchy consisting of local, metropolitan, and wide area nodes tea support optical broadcast and routing modes. Frequencies are shared and reused to enhance network scalability. Electronic access is provided through optical terminals that support multiple services having data rates between 10 Mbps/user and 10 Gbps/user. Of particular interest for this work is the 'B-service,' which simultaneously hops frequency and time slots on each optical terminal to allow frequency sharing within the AON. B-service provides 1.244 Gbps per optical terminal, with bandwidth for individual connections divided in increments as small as 10 Mbps. We have created interfaces between the AON and commercially available electronic circuit-switched and packet-switched networks. The packet switches provide FDDI (datacomm), T3 (telecomm), and ATM/SONET switching at backplane rates of over 3 Gbps. We show results on network applications that dynamically allocate optical bandwidth between electronic packet-switches based on the offered load presented by users. Bandwidth allocation granularity is proportional to B-Service slots (10-1244 Mbps), and switching times are on the order of one second. We have also studied the effects of wavelength changers upon the network capacity and blocking probabilities in wide area all-optical networks. Wavelength changers allow a change in the carrier frequency (within the network) without disturbing the data modulation. The study includes both a theoretical model of blocking probabilities based on network design parameters, and a computer simulation of blocking in networks with and

  3. Investigation of performance issues affecting optical circuit and packet switched WDM networks

    OpenAIRE

    Smyth, Frank

    2009-01-01

    Optical switching represents the next step in the evolution of optical networks. This thesis describes work that was carried out to examine performance issues which can occur in two distinct varieties of optical switching networks. Slow optical switching in which lightpaths are requested, provisioned and torn down when no longer required is known as optical circuit switching (OCS). Services enabled by OCS include wavelength routing, dynamic bandwidth allocation and protection switching...

  4. A new network architecture for future optical networks : coarse optical circuit switching by default, rerouting over circuits for adaptation

    OpenAIRE

    Chou, Jerry

    2009-01-01

    As Internet traffic continues to grow unabated at an exponential rate, it is unclear whether or not the existing packet routing network architecture based on electronic routers will continue to scale at the necessary pace. On the other hand, optical fiber and switching elements have demonstrated an abundance of capacity that appears to be unmatched by electronic routers. In particular, the simplicity of circuit switching makes it well-suited for optical implementations. Therefore, given the r...

  5. Software-Controlled Next Generation Optical Circuit Switching for HPC and Cloud Computing Datacenters

    OpenAIRE

    Muhammad Imran; Martin Collier; Pascal Landais; Kostas Katrinis

    2015-01-01

    In this paper, we consider the performance of optical circuit switching (OCS) systems designed for data center networks by using network-level simulation. Recent proposals have used OCS in data center networks but the relatively slow switching times of OCS-MEMS switches (10–100 ms) and the latencies of control planes in these approaches have limited their use to the largest data center networks with workloads that last several seconds. Herein, we extend the applicability and generality of the...

  6. Compact Hybrid Subsystem of 16 Channel Optical Demultiplexer, 2x2 Switches, Optical Power Monitors and Control Circuit

    Institute of Scientific and Technical Information of China (English)

    Kenichiro; Takahashi; Toshihiko; Kishimoto; Shintaro; Mouri; Youichi; Hata; Hideaki; Yusa; Mitsuaki; Tamura; Kazuhito; Saito; Hisao; Maki

    2003-01-01

    A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor the optical power level by software commands. The size of the subsystem is 170x200x30(mm).

  7. Software-Controlled Next Generation Optical Circuit Switching for HPC and Cloud Computing Datacenters

    Directory of Open Access Journals (Sweden)

    Muhammad Imran

    2015-11-01

    Full Text Available In this paper, we consider the performance of optical circuit switching (OCS systems designed for data center networks by using network-level simulation. Recent proposals have used OCS in data center networks but the relatively slow switching times of OCS-MEMS switches (10–100 ms and the latencies of control planes in these approaches have limited their use to the largest data center networks with workloads that last several seconds. Herein, we extend the applicability and generality of these studies by considering dynamically changing short-lived circuits in software-controlled OCS switches, using the faster switching technologies that are now available. The modelled switch architecture features fast optical switches in a single hop topology with a centralized, software-defined optical control plane. We model different workloads with various traffic aggregation parameters to investigate the performance of such designs across usage patterns. Our results show that, with suitable choices for the OCS system parameters, delay performance comparable to that of electrical data center networks can be obtained.

  8. Introduction to Optical Burst Switching

    OpenAIRE

    KERNÁCS János; SZILÁGYI Szabolcs

    2010-01-01

    Optical Burst Switching (OBS) isconsidered a popular switching paradigm for therealization of all-optical networks due to the balance itoffers between the coarse-grained Optical CircuitSwitching (OSC) and fine-grained Optical PacketSwitching (OPS). Given that the data are switched allopticallyat the burst level, Optical Burst Switchingcombines the transparency of Optical CircuitSwitching with the benefits of statistical multiplexingin Optical Packet Switching.

  9. Optimal Degree of Optical Circuit Switching in IP-over-WDM Networks

    OpenAIRE

    Menne, Ulrich; Raack, Christian; Wessaly, Roland; Kharitonov, Daniel

    2012-01-01

    In this paper, we study the influence of technology, traffic properties and price trends on optimized design of a reference IP-over-WDM network with rich underlying fiber topology. In each network node, we investigate the optimal degree of traffic switching in an optical (lambda) domain versus an electrical (packet) domain, also known as measure of node transparency. This measure is studied in connection to changes in traffic volume, demand affinity, optical circuit speeds and equipment cost....

  10. Optical MEMS platform for low-cost on-chip integration of planar light circuits and optical switching

    Science.gov (United States)

    German, Kristine A.; Kubby, Joel; Chen, Jingkuang; Diehl, James; Feinberg, Kathleen; Gulvin, Peter; Herko, Larry; Jia, Nancy; Lin, Pinyen; Liu, Xueyuan; Ma, Jun; Meyers, John; Nystrom, Peter; Wang, Yao Rong

    2004-07-01

    Xerox Corporation has developed a technology platform for on-chip integration of latching MEMS optical waveguide switches and Planar Light Circuit (PLC) components using a Silicon On Insulator (SOI) based process. To illustrate the current state of this new technology platform, working prototypes of a Reconfigurable Optical Add/Drop Multiplexer (ROADM) and a l-router will be presented along with details of the integrated latching MEMS optical switches. On-chip integration of optical switches and PLCs can greatly reduce the size, manufacturing cost and operating cost of multi-component optical equipment. It is anticipated that low-cost, low-overhead optical network products will accelerate the migration of functions and services from high-cost long-haul markets to price sensitive markets, including networks for metropolitan areas and fiber to the home. Compared to the more common silica-on-silicon PLC technology, the high index of refraction of silicon waveguides created in the SOI device layer enables miniaturization of optical components, thereby increasing yield and decreasing cost projections. The latching SOI MEMS switches feature moving waveguides, and are advantaged across multiple attributes relative to alternative switching technologies, such as thermal optical switches and polymer switches. The SOI process employed was jointly developed under the auspice of the NIST APT program in partnership with Coventor, Corning IntelliSense Corp., and MicroScan Systems to enable fabrication of a broad range of free space and guided wave MicroOptoElectroMechanical Systems (MOEMS).

  11. CIRCUIT SWITCHING VERSUS PACKET SWITCHING

    OpenAIRE

    Sneps-Sneppe, Manfred

    2015-01-01

    Communication specialists around the world are facing the same problem: shifting from circuit switching (CS) to packet switching (CS). Communication service providers are favoring “All-over-IP” technologies hoping to boost their profits by providing multimedia services. The main stakeholder in this field of the paradigm shift is the industry itself: packet switching hardware manufacturers are going to earn billions of dollars and thus pay engineers and journalists many millions for the promot...

  12. A resilience-based comparative study between optical burst switching and optical circuit switching technologies

    OpenAIRE

    Hernández, José Alberto; Aracil, Javier; López Álvarez, Victor; Fernández Palacios, Juan; González de Dios, Óscar

    2006-01-01

    Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. J. A. Hernández, J. Aracil, V. López, J. F. Palacios, and O. G. de Dios, "A resilience-based comparative study between optical...

  13. Stochastic Switching Circuit Synthesis

    OpenAIRE

    Wilhelm, Daniel; Bruck, Jehoshua

    2009-01-01

    Shannon in his 1938 Masterpsilas Thesis demonstrated that any Boolean function can be realized by a switching relay circuit, leading to the development of deterministic digital logic. Here, we replace each classical switch with a probabilistic switch (pswitch). We present algorithms for synthesizing circuits closed with a desired probability, including an algorithm that generates optimal size circuits for any binary fraction. We also introduce a new duality property for series-parallel stocha...

  14. Demonstration of 720×720 optical fast circuit switch for intra-datacenter networks

    Science.gov (United States)

    Ueda, Koh; Mori, Yojiro; Hasegawa, Hiroshi; Matsuura, Hiroyuki; Ishii, Kiyo; Kuwatsuka, Haruhiko; Namiki, Shu; Sato, Ken-ichi

    2016-03-01

    Intra-datacenter traffic is growing more than 20% a year. In typical datacenters, many racks/pods including servers are interconnected via multi-tier electrical switches. The electrical switches necessitate power-consuming optical-to- electrical (OE) and electrical-to-optical (EO) conversion, the power consumption of which increases with traffic. To overcome this problem, optical switches that eliminate costly OE and EO conversion and enable low power consumption switching are being investigated. There are two major requirements for the optical switch. First, it must have a high port count to construct reduced tier intra-datacenter networks. Second, switching speed must be short enough that most of the traffic load can be offloaded from electrical switches. Among various optical switches, we focus on those based on arrayed-waveguide gratings (AWGs), since the AWG is a passive device with minimal power consumption. We previously proposed a high-port-count optical switch architecture that utilizes tunable lasers, route-and-combine switches, and wavelength-routing switches comprised of couplers, erbium-doped fiber amplifiers (EDFAs), and AWGs. We employed conventional external cavity lasers whose wavelength-tuning speed was slower than 100 ms. In this paper, we demonstrate a large-scale optical switch that offers fast wavelength routing. We construct a 720×720 optical switch using recently developed lasers whose wavelength-tuning period is below 460 μs. We evaluate the switching time via bit-error-ratio measurements and achieve 470-μs switching time (includes 10-μs guard time to handle EDFA surge). To best of our knowledge, this is the first demonstration of such a large-scale optical switch with practical switching time.

  15. Polarization diversity circuit for a silicon optical switch using silica waveguides integrated with photonic crystal thin film waveplates

    Science.gov (United States)

    Sugiyama, Koki; Chiba, Takafumi; Kawashima, Takayuki; Kawakami, Shojiro; Takahashi, Hiroshi; Tsuda, Hiroyuki

    2016-03-01

    We propose a compact polarization diversity optical circuit using silica waveguides and photonic crystal waveplates. By setting these circuits at the front and rear of the silicon optical devices, the polarization dependence of the silicon devices can be suppressed. Photonic crystals can be produced artificially using nanolithography, so that the retardation and orientation of the photonic crystal waveplate can be locally varied on a single chip. This enables to dramatically reduce the size of the polarization diversity circuit, which consists of a 1x2 multimode interference (MMI) coupler, two arm waveguides with quarter-waveplates (QWPs), a 2x2 MMI coupler, and output waveguides with half-waveplates (HWPs). The input light, including the transverse electric (TE) and transverse magnetic (TM) modes, is split by the 1x2 MMI coupler. The optical axes of the two QWPs, spaced 125 μm apart, are set to be orthogonal to each other, so that the phases of the TE modes in the two arm waveguides differ by 90 degrees, and those of the TM modes differ by -90 degrees. The TE mode and the TM mode are separated at the outputs of the 2x2 MMI coupler, and the polarization of the light at one of the outputs is aligned to that at the other output by the HWP. In this paper, we designed a 4x8 polarization diversity circuit for a 4x4 silicon optical switch.

  16. Circuit model of Rimfire switch

    International Nuclear Information System (INIS)

    A cascade gaps circuit model for Rimfire switch has been developed. The circuit model includes all stray capacitances and spark channel on-state conduction characteristics. It can not only describe the behavior of Rimfire switch, but also allow analysis of the time varying voltage and current at each part of the switch, describing the internal characters of the switch. PSpice was used to implement the cascade gaps circuit model and simulate a 700 kV Rimfire switch. The simulation shows that, the voltage of the whole switch will be higher than 700 kV when the laser triggered section has broken down but all cascade gaps keep dielectric, and the voltage of all gaps attenuates with high frequency oscillation. (authors)

  17. Static Switching Dynamic Buffer Circuit

    OpenAIRE

    Pandey, A. K.; R. A. Mishra; R. K. Nagaria

    2013-01-01

    We proposed footless domino logic buffer circuit. It minimizes redundant switching at the dynamic and the output nodes. The proposed circuit avoids propagation of precharge pulse to the output node and allows the dynamic node which saves power consumption. Simulation is done using 0.18 µm CMOS technology. We have calculated the power consumption, delay, and power delay product of the proposed circuit and compared the results with the existing circuits for different logic function, loading co...

  18. Optical switches and switching methods

    Energy Technology Data Exchange (ETDEWEB)

    Doty, Michael

    2008-03-04

    A device and method for collecting subject responses, particularly during magnetic imaging experiments and testing using a method such as functional MRI. The device comprises a non-metallic input device which is coupled via fiber optic cables to a computer or other data collection device. One or more optical switches transmit the subject's responses. The input device keeps the subject's fingers comfortably aligned with the switches by partially immobilizing the forearm, wrist, and/or hand of the subject. Also a robust nonmetallic switch, particularly for use with the input device and methods for optical switching.

  19. Clocking Scheme for Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1998-01-01

    A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed.......A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed....

  20. A novel SDN enabled hybrid optical packet/circuit switched data centre network: the LIGHTNESS approach

    OpenAIRE

    Peng, Shuping; Simeonidou, Dimitra; Zervas, George; Spadaro, Salvatore; Perelló Muntan, Jordi; Agraz Bujan, Fernando; Careglio, Davide; Becerra Fontal, Yolanda; Farreras Esclusa, Montserrat

    2014-01-01

    Current over-provisioned and multi-tier data centre networks (DCN) deploy rigid control and management platforms, which are not able to accommodate the ever-growing workload driven by the increasing demand of high-performance data centre (DC) and cloud applications. In response to this, the EC FP7 project LIGHTNESS (Low Latency and High Throughput Dynamic Network Infrastructures for High Performance Datacentre Interconnects) is proposing a new flattened optical DCN arc...

  1. Nonsmooth Modeling and Simulation for Switched Circuits

    CERN Document Server

    Acary, Vincent; Brogliato, Bernard

    2011-01-01

    "Nonsmooth Modeling and Simulation for Switched Circuits" concerns the modeling and the numerical simulation of switched circuits with the nonsmooth dynamical systems (NSDS) approach, using piecewise-linear and multivalued models of electronic devices like diodes, transistors, switches. Numerous examples (ranging from introductory academic circuits to various types of power converters) are analyzed and many simulation results obtained with the INRIA open-source SICONOS software package are presented. Comparisons with SPICE and hybrid methods demonstrate the power of the NSDS approach

  2. Circuit switched optical networks

    DEFF Research Database (Denmark)

    Kloch, Allan

    2003-01-01

    this time by concatenating two interferometric wavelength converters at 20 Gbit/s causing a negligible penalty. The interferometric converters are not only attractive owing to their conversion capabilities. The technique inherently also provide regeneration in terms of pulse reshaping, which is demonstrated...

  3. Intelligent switches of integrated lightwave circuits with core telecommunication functions

    Science.gov (United States)

    Izhaky, Nahum; Duer, Reuven; Berns, Neil; Tal, Eran; Vinikman, Shirly; Schoenwald, Jeffrey S.; Shani, Yosi

    2001-05-01

    We present a brief overview of a promising switching technology based on Silica on Silicon thermo-optic integrated circuits. This is basically a 2D solid-state optical device capable of non-blocking switching operation. Except of its excellent performance (insertion lossmarket segments appropriate for the switch size and technology, followed by a discussion of the basic features of the technology. The discussion is focused on important requirements from the switch and the technology (e.g., insertion loss, power consumption, channel isolation, extinction ratio, switching time, and heat dissipation). The mechanical design is also considered. It must take into account integration of optical fiber, optical planar wafer, analog electronics and digital microprocessor controls, embedded software, and heating power dissipation. The Lynx Photon.8x8 switch is compared to competing technologies, in terms of typical market performance requirements.

  4. Theory of circuit block switch-off

    OpenAIRE

    S. Henzler; J. Berthold; G. Georgakos; Schmitt-Landsiedel, D.

    2005-01-01

    Switching-off unused circuit blocks is a promising approach to supress static leakage currents in ultra deep sub-micron CMOS digital systems. Basic performance parameters of Circuit Block Switch-Off (CBSO) schemes are defined and their dependence on basic circuit parameters is estimated. Therefore the design trade-off between strong leakage suppression in idle mode and adequate dynamic performance in active mode can be supported by simple analytic investigations. Additionally, a guideline for...

  5. Advances in integrated photonic circuits for packet-switched interconnection

    Science.gov (United States)

    Williams, Kevin A.; Stabile, Ripalta

    2014-03-01

    Sustained increases in capacity and connectivity are needed to overcome congestion in a range of broadband communication network nodes. Packet routing and switching in the electronic domain are leading to unsustainable energy- and bandwidth-densities, motivating research into hybrid solutions: optical switching engines are introduced for massive-bandwidth data transport while the electronic domain is clocked at more modest GHz rates to manage routing. Commercially-deployed optical switching engines using MEMS technologies are unwieldy and too slow to reconfigure for future packet-based networking. Optoelectronic packet-compliant switch technologies have been demonstrated as laboratory prototypes, but they have so far mostly used discretely pigtailed components, which are impractical for control plane development and product assembly. Integrated photonics has long held the promise of reduced hardware complexity and may be the critical step towards packet-compliant optical switching engines. Recently a number of laboratories world-wide have prototyped optical switching circuits using monolithic integration technology with up to several hundreds of integrated optical components per chip. Our own work has focused on multi-input to multi-output switching matrices. Recently we have demonstrated 8×8×8λ space and wavelength selective switches using gated cyclic routers and 16×16 broadband switching chips using monolithic multi-stage networks. We now operate these advanced circuits with custom control planes implemented with FPGAs to explore real time packet routing in multi-wavelength, multi-port test-beds. We review our contributions in the context of state of the art photonic integrated circuit technology and packet optical switching hardware demonstrations.

  6. Optical switching device

    NARCIS (Netherlands)

    Broeder, F.J.A. den; Hanzen, R.M.N.; Duine, P.A.; Jungblut, R.M.; Draijer, C.; Roozeboom, F.; Sluis, P. van der

    2000-01-01

    A description is given of an optical switching device (1) comprising a transparent substrate (3), a switching film (5) of a hydride compound of a trivalent transition or rare earth metal having a thickness of 300 nm, and a palladium capping layer (7) having a thickness of 30 nm. The capping layer is

  7. Optical switching systems using nanostructures

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    2004-01-01

    High capacity multiservice optical networks require compact and efficient switches. The potential benefits of optical switch elements based on nanostructured material are reviewed considering various material systems.......High capacity multiservice optical networks require compact and efficient switches. The potential benefits of optical switch elements based on nanostructured material are reviewed considering various material systems....

  8. Low-Voltage Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Bidari, E.; Keskin, M.; Maloberti, F.;

    1999-01-01

    Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications....

  9. POWER MOS FET MODELS FOR "SWITCHING" CIRCUITS

    OpenAIRE

    Rossel, P; Maimouni, R.; Belabadia, M.; Tranduc, Henri; Cordonnier, C.; Bairanzade, M.

    1988-01-01

    A compact model of the Power VDMOS Transistor compatible with the circuit simulator "SPICE2" is described in this article. This model is applied to the simulation of switching circuit with resistive and inductive loads ; comparisons with experimental results are presented.

  10. 160 Gb/s all-optical packet switching field experiment

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; Herrera, J.; Raz, O.;

    2007-01-01

    We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits.......We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits....

  11. Theory of circuit block switch-off

    Directory of Open Access Journals (Sweden)

    S. Henzler

    2004-01-01

    Full Text Available Switching-off unused circuit blocks is a promising approach to supress static leakage currents in ultra deep sub-micron CMOS digital systems. Basic performance parameters of Circuit Block Switch-Off (CBSO schemes are defined and their dependence on basic circuit parameters is estimated. Therefore the design trade-off between strong leakage suppression in idle mode and adequate dynamic performance in active mode can be supported by simple analytic investigations. Additionally, a guideline for the estimation of the minimum time for which a block deactivation is useful is derived.

  12. Staged circuit switching for network computers

    Energy Technology Data Exchange (ETDEWEB)

    Arango, M.; Gelernter, D.; Badr, H.; Bernstein, A.J.

    1983-03-01

    Staged cricuit switching (SCS) is a message-switching technique which combines a new protocol with new communication hardware. Protocol and hardware are designed specifically for networks which are intended to function as integrated, general-purpose MIMD machines, i.e. for network computers. The SCS protocol is a form of circuit switching which degrades automatically into packet switching when unavailable output lines make further extension of a partial circuit impossible. The SCS hardware uses a front-end crossbar switch to multiplex some small number of communication channels among all of a given node's incident links. Together, hardware and protocol represent an attempt to convert spare bandwidth into lower network delays. They also allow experimentation with networks which reconfigure themselves dynamically in response to measured traffic patterns. SCS is compared with packet switching, circuit switching and the virtual cut-through protocol of P. Kermani and L.Kleinrock (see Comput. Networks, vol.3, p.267, 1979, and IEEE Trans. Comput. C-29,12, p.1052, December 1980), and an SCS implementation designed for the SBN network computer is discussed. 23 references.

  13. Optical Packet Switching Demostrator

    DEFF Research Database (Denmark)

    Mortensen, Brian Bach; Berger, Michael Stübert

    2002-01-01

    In the IST project DAVID (data and voice integration over DWDM) work is carried out defining possible architectures of future optical packet switched networks. The feasibility of the architecture is to be verified in a demonstration set-up. This article describes the demonstrator set-up and the...

  14. Switching tests for the LCTF protective dump circuit

    International Nuclear Information System (INIS)

    Each of the six coils in the Large Coil Test Facility (LCTF) has a separate power supply, dump resistor, and switching circuit. Each switching circuit contains five switches, two of which are redundant. The three remaining switches perform separate duties in an emergency dump situation. These three switches were tested to determine their ability to meet the LCTF conditions

  15. Two-resonator circuit quantum electrodynamics: A superconducting quantum switch

    Science.gov (United States)

    Mariantoni, Matteo; Deppe, Frank; Marx, A.; Gross, R.; Wilhelm, F. K.; Solano, E.

    2008-09-01

    We introduce a systematic formalism for two-resonator circuit QED, where two on-chip microwave resonators are simultaneously coupled to one superconducting qubit. Within this framework, we demonstrate that the qubit can function as a quantum switch between the two resonators, which are assumed to be originally independent. In this three-circuit network, the qubit mediates a geometric second-order circuit interaction between the otherwise decoupled resonators. In the dispersive regime, it also gives rise to a dynamic second-order perturbative interaction. The geometric and dynamic coupling strengths can be tuned to be equal, thus permitting to switch on and off the interaction between the two resonators via a qubit population inversion or a shifting of the qubit operation point. We also show that our quantum switch represents a flexible architecture for the manipulation and generation of nonclassical microwave field states as well as the creation of controlled multipartite entanglement in circuit QED. In addition, we clarify the role played by the geometric interaction, which constitutes a fundamental property characteristic of superconducting quantum circuits without a counterpart in quantum-optical systems. We develop a detailed theory of the geometric second-order coupling by means of circuit transformations for superconducting charge and flux qubits. Furthermore, we show the robustness of the quantum switch operation with respect to decoherence mechanisms. Finally, we propose a realistic design for a two-resonator circuit QED setup based on a flux qubit and estimate all the related parameters. In this manner, we show that this setup can be used to implement a superconducting quantum switch with available technology.

  16. Nanoeletromechanical switch and logic circuits formed therefrom

    Science.gov (United States)

    Nordquist, Christopher D.; Czaplewski, David A.

    2010-05-18

    A nanoelectromechanical (NEM) switch is formed on a substrate with a source electrode containing a suspended electrically-conductive beam which is anchored to the substrate at each end. This beam, which can be formed of ruthenium, bows laterally in response to a voltage applied between a pair of gate electrodes and the source electrode to form an electrical connection between the source electrode and a drain electrode located near a midpoint of the beam. Another pair of gate electrodes and another drain electrode can be located on an opposite side of the beam to allow for switching in an opposite direction. The NEM switch can be used to form digital logic circuits including NAND gates, NOR gates, programmable logic gates, and SRAM and DRAM memory cells which can be used in place of conventional CMOS circuits, or in combination therewith.

  17. Gain-assisted optical switching in plasmonic nanocavities

    Institute of Scientific and Technical Information of China (English)

    Yun Shen; Guoping Yu; Jiwu Fu; Liner Zou

    2012-01-01

    A plasmonic cavity filled with active material is proposed to explain optical switching.Optical properties,including transmission,response time,and field distribution of on/off state,are numerically investigated.We demonstrate that such a gain-assisted plasmonic structure can achieve optical switching in the nanodomain and shorten the switching time to the subpicosecond level.Our results indicate the potential application of the proposed structure in optical communication and photonic integrated circuits.%A plasmonic cavity filled with active material is proposed to explain optical switching. Optical properties, including transmission, response time, and field distribution of on/off state, are numerically investigated. We demonstrate that such a gain-assisted plasmonic structure can achieve optical switching in the nan-odomain and shorten the switching time to the subpicosecond level. Our results indicate the potential application of the proposed structure in optical communication and photonic integrated circuits.

  18. The Synthesis and Analysis of Stochastic Switching Circuits

    OpenAIRE

    Zhou, Hongchao; Loh, Po-Ling; Bruck, Jehoshua

    2012-01-01

    Stochastic switching circuits are relay circuits that consist of stochastic switches called pswitches. The study of stochastic switching circuits has widespread applications in many fields of computer science, neuroscience, and biochemistry. In this paper, we discuss several properties of stochastic switching circuits, including robustness, expressibility, and probability approximation. First, we study the robustness, namely, the effect caused by introducing an error of size \\epsilon to each ...

  19. Cost functions in optical burst-switched networks

    OpenAIRE

    Klusek, Bartlomiej

    2006-01-01

    Optical Burst Switching (OBS) is a new paradigm for an all-optical Internet. It combines the best features of Optical Circuit Switching (OCS) and Optical Packet Switching (OPS) while avoidmg the mam problems associated with those networks .Namely, it offers good granularity, but its hardware requirements are lower than those of OPS. In a backbone network, low loss ratio is of particular importance. Also, to meet varying user requirements, it should support multiple classes of service. In ...

  20. Optical packet switched networks

    DEFF Research Database (Denmark)

    Hansen, Peter Bukhave

    1999-01-01

    in interferometric wavelength converters is investigated showing that a 10 Gbit/s 19 4x4 swich blocks can be cascaded at a BER of 10-14. An analytical traffic model enables the calculation of the traffice performance of a WDM packet network. Hereby the importance of WDM and wavelegth conversion in the switch blocks...... is investigated showing more constant gain characteristics and an increased saturation input power from -17 to -4 dBm. Dynamically, the GC-SOA is demonstrated to perform better at bit rates over 10 Gbit/s for RZ than NRZ signals. Additionally, a 4x4 passive InP mach-Zehnder interferometric space switch has been...... power dynamic range (IPDR). Moreover, the IPDR of the IWC alone is only -3.5 dB at 10 Gbit/s, however, control schemes are introduced yielding an IPDR of both -28 dB and -40 dB. Finally, the feasibility of an all-optical WDM packet switch block is demonstrated at 20 Gbit/s for a 4x4 switch block with 4...

  1. Optically coupled cavities for wavelength switching

    International Nuclear Information System (INIS)

    An optical bistable device which presents hysteresis behavior is proposed and experimentally demonstrated. The system finds applications in wavelength switching, pulse reshaping and optical bistability. It is based on two optically coupled cavities named master and slave. Each cavity includes a semiconductor optical amplifier (SOA), acting as the gain medium of the laser, and two pair of fiber Bragg gratings (FBG) which define the lasing wavelength (being different in each cavity). Finally, a variable optical coupler (VOC) is employed to couple both cavities. Experimental characterization of the system performance is made analyzing the effects of the coupling coefficient between the two cavities and the driving current in each SOA. The properties of the hysteretic bistable curve and switching can be controlled by adjusting these parameters and the loss in the cavities. By selecting the output wavelength (λ1 or λ2) with an external filter it is possible to choose either the invert or non-invert switched signal. Experiments were developed employing both optical discrete components and a photonic integrated circuit. They show that for 8 m-long cavities the maximum switching frequency is about 500 KHz, and for 4 m-long cavities a minimum rise-time about 21 ns was measured. The switching time can be reduced by shortening the cavity lengths and using photonic integrated circuits.

  2. Modeling digital switching circuits with linear algebra

    CERN Document Server

    Thornton, Mitchell A

    2014-01-01

    Modeling Digital Switching Circuits with Linear Algebra describes an approach for modeling digital information and circuitry that is an alternative to Boolean algebra. While the Boolean algebraic model has been wildly successful and is responsible for many advances in modern information technology, the approach described in this book offers new insight and different ways of solving problems. Modeling the bit as a vector instead of a scalar value in the set {0, 1} allows digital circuits to be characterized with transfer functions in the form of a linear transformation matrix. The use of transf

  3. Integrated photonic switches for nanosecond packet-switched optical wavelength conversion

    Science.gov (United States)

    Fidaner, Onur; Demir, Hilmi Volkan; Sabnis, Vijit A.; Zheng, Jun-Fei; Harris, James S., Jr.; Miller, David A. B.

    2006-01-01

    We present a multifunctional photonic switch that monolithically integrates an InGaAsP/InP quantum well electroabsorption modulator and an InGaAs photodiode as a part of an on-chip, InP optoelectronic circuit. The optical multifunctionality of the switch offers many configurations to allow for different optical network functions on a single chip. Here we experimentally demonstrate GHz-range optical wavelength-converting switching with only ~10 mW of absorbed input optical power, electronically controlled packet switching with a reconfiguration time of switching in <300 ps.

  4. Optically controllable molecular logic circuits

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Takahiro, E-mail: t-nishimura@ist.osaka-u.ac.jp; Fujii, Ryo; Ogura, Yusuke; Tanida, Jun [Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-07-06

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.

  5. Optically controllable molecular logic circuits

    International Nuclear Information System (INIS)

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals

  6. 49 CFR 236.732 - Controller, circuit; switch.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit; switch. 236.732 Section 236.732 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by...

  7. Analysis of a digital microstrip optical switch: a novel method

    Science.gov (United States)

    Al-Ruwaihi, Khalid M.; Hindy, Moataza A.

    1997-02-01

    A time domain analysis of an optically controlled digital microstrip switch for microwave integrated circuits on Si substrates is studied. A new model for high-frequency pulse propagation on a microstrip optical switch for different optical parameters is presented. A frequency-dependent macromodel for a microstrip line with a gap is implemented in Spice 3, taking into consideration high-frequency pulse dispersion, conductor and dielectric losses, metallization thickness, gap length, and different optical parameters such as optical energy, surface recombination velocities, and diffusion of generated carriers. In addition, the developed model has been used to optimize the switching frequency, gap length, level of optical power, and suitable substrate material parameters.

  8. Reconfigurable SDM Switching Using Novel Silicon Photonic Integrated Circuit

    CERN Document Server

    Ding, Yunhong; Dalgaard, Kjeld; Ye, Feihong; Asif, Rameez; Gross, Simon; Withford, Michael J; Galili, Michael; Morioka, Toshio; Oxenlowe, Leif Katsuo

    2016-01-01

    Space division multiplexing using multicore fibers is becoming a more and more promising technology. In space-division multiplexing fiber network, the reconfigurable switch is one of the most critical components in network nodes. In this paper we for the first time demonstrate reconfigurable space-division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-on-insulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7x7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than -30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained for the whole C-band. 1 Tb/s/core transmission over a 2-km 7-core fiber and space-division multiplexing swi...

  9. Statistical Estimation of the ,Switching Activity in VLSI Circuits

    OpenAIRE

    Farid N. Najm; Michael G. Xakellis

    1998-01-01

    Higher levels of integration have led to a generation of integrated circuits for which power dissipation and reliability are major design concerns. In CMOS circuits, both of these problems are directly related to the extent of circuit switching activity. The average number of transitions per second at a circuit node is a measure of switching activity that has been called the transition density. This paper presents a statistical simulation technique to estimate individual node transition densi...

  10. Variable time-period optical switching: a novel OBS implementation

    Institute of Scientific and Technical Information of China (English)

    Jinsong Zhang(张劲松); Mingcui Cao(曹明翠); Fengguang Luo(罗风光); Tao Chen(陈涛)

    2003-01-01

    In this paper, we proposed a novel optical switching method based on optical burst switching (OBS), we call it variable time-period optical switching (VTPOS). It can both support circuit services and other immerged packet services. It has better usability of bandwidth, shorter offset and latency time than others of unidirectional transport signaling mechanisms for OBS. It supports deflection switching for improve blocking performance without the need of schedule buffer. It introduces a time pointer and phase indicator that made synchronous more precisely and requires less guard time, it also classifies the different services classes with a relative QoS model.

  11. Fast integrated optical switching by the protein bacteriorhodopsin

    Science.gov (United States)

    Fábián, László; Wolff, Elmar K.; Oroszi, László; Ormos, Pál; Dér, András

    2010-07-01

    State-of-the-art photonic integration technology is ready to provide the passive elements of optical integrated circuits, based either on silicon, glass or plastic materials. The bottleneck is to find the proper nonlinear optical (NLO) materials in waveguide-based integrated optical circuits for light-controlled active functions. Recently, we proposed an approach where the active role is performed by the chromoprotein bacteriorhodopsin as an NLO material, that can be combined with appropriate integrated optical devices. Here we present data supporting the possibility of switching based on a fast photoreaction of bacteriorhodopsin. The results are expected to have important implications for photonic switching technology.

  12. Flexible circuits with integrated switches for robotic shape sensing

    Science.gov (United States)

    Harnett, C. K.

    2016-05-01

    Digital switches are commonly used for detecting surface contact and limb-position limits in robotics. The typical momentary-contact digital switch is a mechanical device made from metal springs, designed to connect with a rigid printed circuit board (PCB). However, flexible printed circuits are taking over from the rigid PCB in robotics because the circuits can bend while carrying signals and power through moving joints. This project is motivated by a previous work where an array of surface-mount momentary contact switches on a flexible circuit acted as an all-digital shape sensor compatible with the power resources of energy harvesting systems. Without a rigid segment, the smallest commercially-available surface-mount switches would detach from the flexible circuit after several bending cycles, sometimes violently. This report describes a low-cost, conductive fiber based method to integrate electromechanical switches into flexible circuits and other soft, bendable materials. Because the switches are digital (on/off), they differ from commercially-available continuous-valued bend/flex sensors. No amplification or analog-to-digital conversion is needed to read the signal, but the tradeoff is that the digital switches only give a threshold curvature value. Boundary conditions on the edges of the flexible circuit are key to setting the threshold curvature value for switching. This presentation will discuss threshold-setting, size scaling of the design, automation for inserting a digital switch into the flexible circuit fabrication process, and methods for reconstructing a shape from an array of digital switch states.

  13. Development of optical packet and circuit integrated ring network testbed.

    Science.gov (United States)

    Furukawa, Hideaki; Harai, Hiroaki; Miyazawa, Takaya; Shinada, Satoshi; Kawasaki, Wataru; Wada, Naoya

    2011-12-12

    We developed novel integrated optical packet and circuit switch-node equipment. Compared with our previous equipment, a polarization-independent 4 × 4 semiconductor optical amplifier switch subsystem, gain-controlled optical amplifiers, and one 100 Gbps optical packet transponder and seven 10 Gbps optical path transponders with 10 Gigabit Ethernet (10GbE) client-interfaces were newly installed in the present system. The switch and amplifiers can provide more stable operation without equipment adjustments for the frequent polarization-rotations and dynamic packet-rate changes of optical packets. We constructed an optical packet and circuit integrated ring network testbed consisting of two switch nodes for accelerating network development, and we demonstrated 66 km fiber transmission and switching operation of multiplexed 14-wavelength 10 Gbps optical paths and 100 Gbps optical packets encapsulating 10GbE frames. Error-free (frame error rate < 1×10(-4)) operation was achieved with optical packets of various packet lengths and packet rates, and stable operation of the network testbed was confirmed. In addition, 4K uncompressed video streaming over OPS links was successfully demonstrated.

  14. The circuit of high voltage gating switch of variable delay

    International Nuclear Information System (INIS)

    A high voltage gating switch of variable delay for photomultiplier tube has been fabricated. Which variable delay range is changeable and the gating pulse has fast rise time. The circuit has been applied for getting signal detection of laser radar

  15. Compact SCR trigger circuit for ignitron switch operates efficiently

    Science.gov (United States)

    Foster, L. E.

    1965-01-01

    Trigger circuit with two series-connected SCR triggers an ignitron switch used to discharge high-energy capacitor banks. It does not require a warmup period and operates at relatively high efficiency.

  16. A multi-ring optical packet and circuit integrated network with optical buffering.

    Science.gov (United States)

    Furukawa, Hideaki; Shinada, Satoshi; Miyazawa, Takaya; Harai, Hiroaki; Kawasaki, Wataru; Saito, Tatsuhiko; Matsunaga, Koji; Toyozumi, Tatuya; Wada, Naoya

    2012-12-17

    We newly developed a 3 × 3 integrated optical packet and circuit switch-node. Optical buffers and burst-mode erbium-doped fiber amplifiers with the gain flatness are installed in the 3 × 3 switch-node. The optical buffer can prevent packet collisions and decrease packet loss. We constructed a multi-ring optical packet and circuit integrated network testbed connecting two single-ring networks and a client network by the 3 × 3 switch-node. For the first time, we demonstrated 244 km fiber transmission and 5-node hopping of multiplexed 14-wavelength 10 Gbps optical paths and 100 Gbps optical packets encapsulating 10 Gigabit Ethernet frames on the testbed. Error-free (frame error rate < 1 × 10(-4)) operation was achieved with optical packets of various packet lengths. In addition, successful avoidance of packet collisions by optical buffers was confirmed.

  17. A Demonstration of Automatically Switched Optical Network

    Institute of Scientific and Technical Information of China (English)

    Weisheng Hu; Qingji Zeng; Yaohui Jin; Chun Jiang; Yue Wang; Xiaodong Wang; Chunlei Zhang; Yang Lu; Buwei Xu; Peigang Hu

    2003-01-01

    We build an automatically switched optical network (ASON) testbed with four optical cross-connect nodes. Many fundamental ASON features are demonstrated, which is implemented by control protocols based on generalized multi-protocol label switching (GMPLS) framework.

  18. Novel implementations of optical switch control module and 3D-CSP for 10 Gbps active optical access system

    Science.gov (United States)

    Wakayama, Koji; Okuno, Michitaka; Matsuoka, Yasunobu; Hosomi, Kazuhiko; Sagawa, Misuzu; Sugawara, Toshiki

    2009-11-01

    We propose an optical switch control procedure for high-performance and cost-effective 10 Gbps Active Optical Access System (AOAS) in which optical switches are used instead of optical splitters in PON (Passive Optical Network). We demonstrate the implemented optical switch control module on Optical Switching Unit (OSW) with logic circuits works effectively. We also propose a compact optical 3D-CSP (Chip Scale Package) to achieve the high performance of AOAS without losing cost advantage of PON. We demonstrate the implemented 3D-CSP works effectively.

  19. Identification of current attacks and their counter measures in Optical Burst Switched (OBS) network

    OpenAIRE

    Siddharth Singh Chouhan; Prof. Sanjay Sharma

    2012-01-01

    As day by day application grows internet requires large amount of bandwidth. Optical Burst Switching (OBS) is the next generation optical Internet with IP over WDM as the core architecture. It can achieve a balance between Optical Circuit Switching (OCS) and Optical Packet Switching (OPS). Optical network supports huge bandwidth and transmits data at an average rate of 50Tb/s. But we need to exploit the fiber’s huge bandwidth through WDM which is the current favorite multiplexing technology i...

  20. Soft switching DC/DC converter using auxiliary circuits

    OpenAIRE

    Jaroslav Dudrik; Vladimír Ruščin

    2008-01-01

    A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.

  1. Ultrafast photonic crystal optical switching

    Institute of Scientific and Technical Information of China (English)

    GONG Qi-huang; HU Xiao-yong

    2006-01-01

    Photonic crystal,a novel and artificial photonic material with periodic dielectric distribution,possesses photonic bandgap and can control the propagation states of photons.Photonic crystal has been considered to be a promising candidate for the future integrated photonic devices.The properties and the fabrication method of photonic crystal are expounded.The progresses of the study of ultrafast photonic crystal optical switching are discussed in detail.

  2. High Frequency Soft Switching Of PWM Boost Converter Using Auxiliary Resonant Circuit

    OpenAIRE

    C. P. Sai Kiran; M. Vishnu Vardhan

    2014-01-01

    This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequency of PWM converters is increased its switching losses and conduction losses also in...

  3. Parity Checking and Generating Circuit with Nonlinear Material in All-Optical Domain

    Institute of Scientific and Technical Information of China (English)

    Kuladeep Roy Chowdhury; Debduti De; Sourangshu Mukhopadhyay

    2005-01-01

    @@ An all-optical parity checker and parity bit generator circuit is proposed, in which optical non-linear materials are used as switching devices. High-speed (above GHz) logic operations can be achieved by this all-optical circuit that is tremendously fast than its equivalent electronic counterpart. Here these circuits are used to check the errors in optical data through a transmission line.

  4. Node design in optical packet switched networks

    DEFF Research Database (Denmark)

    Nord, Martin

    2006-01-01

    proposed parallel designs to overcome scalability constraints and to support migration scenarios. Furthermore, it has proposed and demonstrated optical input processing schemes for hybrids networks to simultaneously support OPS and Optical Circuit Switching. Quality of Service (QoS) differentiation enables...... adapting network performance to the different acceptable packet loss rate levels of supported applications, while improving overall bandwidth efficiency. The project has evaluated QoS differentiation methods and proposed schemes with improved efficiency, which also include jitter sensitivity as a Qo......S parameter. Finally, the thesis includes a proposal for a node design and associated MAC protocol for an OPS ring topology metropolitan area network with high throughput and fairness, also for unbalanced traffic....

  5. Noise Analysis of Switched-Current Circuits

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Harald Holger; Bogason, Gudmundur

    1998-01-01

    The understanding of noise in analog sampled data systems is vital for the design of high resolution circuitry. In this paper a general description of sampled and held noise is presented. The noise calculations are verified by measurements on an analog delay line implemented using switched-curren...

  6. Sampled Noise in Switched Current Circuits

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Herald Holger; Bogason, Gudmundur

    1997-01-01

    The understanding of noise in analog sampled data systems is vital for the design of high resolution circuitry. In this paper a general description of sampled and held noise is presented. The noise calculations are verified by measurements on an analog delay line implemented using switched...

  7. 49 CFR 234.237 - Reverse switch cut-out circuit.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Reverse switch cut-out circuit. 234.237 Section... Maintenance, Inspection, and Testing Maintenance Standards § 234.237 Reverse switch cut-out circuit. A switch, when equipped with a switch circuit controller connected to the point and interconnected with...

  8. High speed switching circuits for future accelerators

    International Nuclear Information System (INIS)

    We are developing a Klystron modulator power source for ILC (International Linear Collider). This modulator needs 120kV(±0.5%), 140A, 5pps, with a pulse width of 1.7ms, aiming for a compact, low-cost and reliable design. To meet these requirements, we propose solid state, chopper controlled pulsed power generator using Marx-topology. This paper shows circuit simulation and prototype experimental results. (author)

  9. Increasing of Switching Abilities of High Voltage Circuit Breakers

    OpenAIRE

    RUSTEMLI, Sabir

    2015-01-01

    The most effective way of increasing switching abilities of high voltage circuit breakers in energy transmission systems is to influence around zero degree to short circuit currents (Maljkovic Z et al 2000; Gashimov, A.M et al. 2001;Antipov, K.M et al. 1985; Gashimov A.M 1991). For this reason, transformers neutral points should be grounded variously for limitation of asymmetric short circuit currents. But another way for this limitation is grounded of transformers neutral points over non-lin...

  10. Power circuit design master from rectifier to switching regulator

    International Nuclear Information System (INIS)

    It is divided into two parts to introduce of power circuit design . The first part deals with design for regulator of dropper type such as rectifier circuit design, power for the simplest stabilizing and know-how of series regulator design. The second part lists switching regulator design, including regulator design with chopper type, RCC type, forward converter design, DC-DC converter, uninterruptible power supply design, high-power design, know-how for level packing technology for heat dissipation and new technology of power circuit.

  11. New fast switches for the Tore Supra ohmic heating circuit

    International Nuclear Information System (INIS)

    The Tore-Supra ohmic heating circuit is equipped with four fast make switches and one fast opening switch. After many years of operation, it became necessary to substitute this equipment by modern components with similar ratings. An extensive research has been undertaken to find fast switches able to withstand more than 2500 operations per year without maintenance, at a make current of 54 kA, a voltage of 12 kV and with a closing time of less than 15 ms. At the end of the investigation, it was decided to replace the old components by fast mechanical switches proposed by the Efremov Institute and based on a prototype developed for ITER. This paper presents the technical requirements and the characteristics of the switches and describes the operational experience gained with these components during operating campaigns of 2002 and 2003. (authors)

  12. Novel analog switching circuit for van der Pauw measurements

    OpenAIRE

    David, T.; Molchadsky, I.; Somechi, A.; Rosenbaum, R.

    2005-01-01

    A simple electronic circuit is described using four common and very inexpensive analog multiplexer/demultiplexer chips. These analog switches are used to select eight different wiring configurations to a van der Pauw sample. Several interfacing schemes to a PC are suggested. The van der Pauw resistivity and Hall voltage expressions are also summarized.

  13. An integrated circuit/packet switched video conferencing system

    International Nuclear Information System (INIS)

    The HEP Network Resource Center (HEPNRC) at Fermilab and the Collider Detector Facility (CDF) collaboration have evolved a flexible, cost-effective, widely accessible video conferencing system for use by high energy physics collaborations and others wishing to use video conferencing. No current systems seemed to fully meet the needs of high energy physics collaborations. However, two classes of video conferencing technology: circuit-switched and packet-switched, if integrated, might encompass most of HEPS's needs. It was also realized that, even with this integration, some additional functions were needed and some of the existing functions were not always wanted. HEPNRC with the help of members of the CDF collaboration set out to develop such an integrated system using as many existing subsystems and components as possible. This system is called VUPAC (Video conferencing Using Packets and Circuits). This paper begins with brief descriptions of the circuit-switched and packet-switched video conferencing systems. Following this, issues and limitations of these systems are considered. Next the VUPAC system is described. Integration is accomplished primarily by a circuit/packet video conferencing interface. Augmentation is centered in another subsystem called MSB (Multiport MultiSession Bridge). Finally, there is a discussion of the future work needed in the evolution of this system. (author)

  14. Two-resonator circuit QED: A superconducting quantum switch

    International Nuclear Information System (INIS)

    Coupling different kind of superconducting (sc) qubits to on-chip microwave resonators has strongly advanced the field of circuit QED. Regarding the application of circuit QED systems in quantum information processing it would be highly desirable to switch on and off the interaction between two resonators. We introduce a formalism for two-resonator circuit QED where two on-chip microwave resonators are simultaneously coupled to one sc qubit. In this three-circuit network, the qubit mediates a geometric and a dynamic second-order interaction between the two resonators. These two coupling strengths can be tuned to be equal by varying the qubit operation point, thus permitting to switch on and off the interaction between the resonators. We discuss the effect of the qubit on the dynamic second-order coupling and how it can be deliberately manipulated to realize a sc quantum switch. Finally, we present a realistic design for implementing a two-resonator circuit QED setup based on a flux qubit and show preliminary experimental results.

  15. Moving the boundary between wavelength resources in optical packet and circuit integrated ring network.

    Science.gov (United States)

    Furukawa, Hideaki; Miyazawa, Takaya; Wada, Naoya; Harai, Hiroaki

    2014-01-13

    Optical packet and circuit integrated (OPCI) networks provide both optical packet switching (OPS) and optical circuit switching (OCS) links on the same physical infrastructure using a wavelength multiplexing technique in order to deal with best-effort services and quality-guaranteed services. To immediately respond to changes in user demand for OPS and OCS links, OPCI networks should dynamically adjust the amount of wavelength resources for each link. We propose a resource-adjustable hybrid optical packet/circuit switch and transponder. We also verify that distributed control of resource adjustments can be applied to the OPCI ring network testbed we developed. In cooperation with the resource adjustment mechanism and the hybrid switch and transponder, we demonstrate that automatically allocating a shared resource and moving the wavelength resource boundary between OPS and OCS links can be successfully executed, depending on the number of optical paths in use.

  16. Spatial and planar optical circuit for flexible ROADM

    Science.gov (United States)

    Shikama, Kota; Ikuma, Yuichiro; Suzuki, Kenya; Takahashi, Tetsuo

    2016-02-01

    A high port count wavelength selective switch (HPC-WSS) is a key component when constructing colorless, directionless, and contentionless ROADM because it provides increased flexibility and scalability. We have been developing HPC-WSSs by combining a waveguide-based optical frontend and free-space optics, which we call a spatial and planar optical circuit (SPOC) platform. In this paper, we present an HPC-WSS and a low-loss transponder aggregator based on a SPOC platform, and we also describe the reliability of the frontend, which is a key enabler for the SPOC platform.

  17. Ultra-stable optical amplifier technologies for dynamic optical switching networks

    Science.gov (United States)

    Shiraiwa, M.; Tsang, K. S.; Man, R.; Puttnam, B. J.; Awaji, Y.; Wada, N.

    2015-01-01

    High-capacity fiber-optic communications are promising technologies to satisfy people's continuously growing demands for bandwidth hungry data services. Multi-wavelength optical circuit switching (OCS) technology is already widely deployed, however, with the limited number of transceivers equipped at each optical node and other constraints, the number of lightpaths which can be established and employed simultaneously in an optical network is restricted. This reduces the utilization efficiency of wavelength resources. Comparing to OCS, dynamic optical switching systems such as optical packet switching (OPS) offer higher efficiency in terms of wavelength resource utilization and have the potential to share more of the wavelength resources on fiber-links between larger numbers of users simultaneously. In such networks, bursty input signals or changes in traffic density may cause optical power surges that can damage optical components or impose gain transients on the signals that impair signal quality. A common approach for reducing gain transients is to employ electrical automatic gain control (AGC) or optical gain-clamping by optical feedback (OFB). AGC may be limited by the speed of the feedback circuit and result in additional transients. Meanwhile OFB can clamp the gain of power varying optical signals without transient but can introduce amplitude fluctuations caused by relaxation oscillations in the lasing cavity for large input power fluctuations. We propose and demonstrate a novel scheme for suppressing the power transients and the relaxation oscillations. This scheme can be utilized in optical amplifiers even if the optical feedback is employed.

  18. New circuit switching techniques in on-chip networks

    OpenAIRE

    Shaoteng, Liu

    2015-01-01

    Network on Chip (NoC) is proposed as a promising technology to address the communication challenges in deep sub-micron era. NoC brings network-based communication into the on-chip environment and tackles the problems like long wire complexities, bandwidth scaling and so on. After more than a decade's evolution and development, there are many NoC architectures and solutions available. Nevertheless, NoCs can be classi_ed into two categories: packet switched NoC and circuit switched NoC. In this...

  19. QKD-Based Secured Burst Integrity Design for Optical Burst Switched Networks

    Science.gov (United States)

    Balamurugan, A. M.; Sivasubramanian, A.; Parvathavarthini, B.

    2016-03-01

    The field of optical transmission has undergone numerous advancements and is still being researched mainly due to the fact that optical data transmission can be done at enormous speeds. It is quite evident that people prefer optical communication when it comes to large amount of data involving its transmission. The concept of switching in networks has matured enormously with several researches, architecture to implement and methods starting with Optical circuit switching to Optical Burst Switching. Optical burst switching is regarded as viable solution for switching bursts over networks but has several security vulnerabilities. However, this work exploited the security issues associated with Optical Burst Switching with respect to integrity of burst. This proposed Quantum Key based Secure Hash Algorithm (QKBSHA-512) with enhanced compression function design provides better avalanche effect over the conventional integrity algorithms.

  20. Optical integrated circuits and networks on microscale/nanoscale

    Science.gov (United States)

    Lee, El-Hang; Lee, S. G.; O, B. H.; Park, S. G.; Kim, K. H.; Song, S. H.

    2007-02-01

    We present an overview of our work on the design and fabrication of micro/nano-scale photonic circuits and networks on what we call "optical printed circuit boards" (O-PCBs) and "VLSI photonic integrated circuit chips"(VLSI-PICs) of generic and application-specific nature. The O-PCBs and photonic chips consist of 2-dimensional planar arrays of optical wires, circuits, and networks of micro/nano-scale to perform the functions of sensing, storing, transporting, processing, switching, routing, and distributing optical signals on flat boards or chips. We describe and discuss scientific and technological issues concerning the miniaturization, interconnection and integration of micro/nano-scale photonic devices, circuits, and networks leading to small and very large scale integration in terms of photonic scaling rules and discuss their use for the design and fabrication of the photonic integrated circuits and networks. Design rules for the miniaturization and integration of the micro/nano-photonic systems are discussed in comparison with those of the micro/nano-electronic systems. Materials include polymer/organic materials and silicon materials. Structural bases include photonic crystals, ring resonators, and plasmonic structures. Compatibility issues between diverse materials and devices are discussed especially in regard to applications. Recent progresses and examples are presented.

  1. Identification of current attacks and their counter measures in Optical Burst Switched (OBS network

    Directory of Open Access Journals (Sweden)

    Siddharth Singh Chouhan

    2012-03-01

    Full Text Available As day by day application grows internet requires large amount of bandwidth. Optical Burst Switching (OBS is the next generation optical Internet with IP over WDM as the core architecture. It can achieve a balance between Optical Circuit Switching (OCS and Optical Packet Switching (OPS. Optical network supports huge bandwidth and transmits data at an average rate of 50Tb/s. But we need to exploit the fiber’s huge bandwidth through WDM which is the current favorite multiplexing technology in Optical communication networks. OBS is a trusted mechanism used for optical switching. Optical burst switching has been positioned as a viable means of implementing optical communication efficiently. This review paper identifies potential threats to security in OBS networks. Solutions in each category are examined, and research directions are presented.

  2. Threats in Optical Burst Switched Network

    Directory of Open Access Journals (Sweden)

    P. Siva Subramanian

    2011-05-01

    Full Text Available Optical network is a viable network for future communication, which transmits data at an average rate of 50Tb/s. Optical Burst Switching is a trusted mechanism used for Optical network. There is a good amount of research done in the area of security in Optical networks. In addition, the issues related to physical network security has been dealt with respect to Optical networks. Our proposed work is intend to find the possible security threats that may happen in Optical Burst Switched Networks and the counter measures are examined separately. The NS-2 simulator with modified OBS patch is used to verify and validate the proposed mechanism

  3. Analogue Behavioral Modeling of Switched-Current Building Block Circuits

    Institute of Scientific and Technical Information of China (English)

    ZENG Xuan; WANG Wei; SHI Jianlei; TANG Pushan; D.ZHOU

    2001-01-01

    This paper proposes a behavioral modeling technique for the second-generation switched-current building block circuits. The proposed models are capable of capturing the non-ideal behavior of switched-current circuits, which includes the charge injection effects and device mismatch effects. As a result, system performance degradations due to the building block imperfections can be detected at the early design stage by fast behavioral simulations. To evaluate the accuracy of the proposed models, we developed a time-domain behavioral simulator. Experimental results have shown that compared with SPICE, the behavioral modeling error is less than 2.15%, while behavioral simulation speed up is 4 orders in time-domain.

  4. Double-Teeth-Shaped Plasmonic Waveguide Electro-Optical Switches

    Institute of Scientific and Technical Information of China (English)

    ZHU Jia-Hu; HUANG Xu-Guang; MEI Xian

    2011-01-01

    @@ An electro-optical switch based on a plasmonic T-shaped waveguide structure with a double-teeth-shaped waveguide filled with 4-dimet4ylamino-N-methyl-4stilbazolium tosylate is proposed and numerically investigated.TheFinite-difference time domain simulation results reveal that the structure can operate as a circuit switch by controlling the external voltages V1 and/or V2.The proposed structure can also operate as a variable optical attenuator, which can continuously attenuate the power of a light beam from 6dB to 30dB by an external electrical field.The structure is of small size of a few hundred nanometers.Our results may open a possibility to construct nanoscale high-density photonic integration circuits.

  5. Ultrafast all-optical switching in bacteriorhodopsin

    Science.gov (United States)

    Roy, Sukhdev; Singh, C. P.; Reddy, K. P. J.

    2001-04-01

    All-optical switching has been demonstrated in bacteriorhodopsin based on excited-state nonlinear absorption. A probe laser beam at 640 nm corresponding to the O-state absorption maximum is switched due to a strong pulsed pump laser beam at 570 nm, that corresponds to the maximum ground state absorption. We have studied the effect of variation in pulse width and in small signal absorption coefficient on the switching characteristics. The switching time decreases as the pulse width of the pump beam decreases and the small signal absorption coefficient increases. The switching contrast depends mainly on the peak pumping intensity.

  6. The stochastic behavior of a molecular switching circuit with feedback

    Directory of Open Access Journals (Sweden)

    Smith Eric

    2007-05-01

    Full Text Available Abstract Background Using a statistical physics approach, we study the stochastic switching behavior of a model circuit of multisite phosphorylation and dephosphorylation with feedback. The circuit consists of a kinase and phosphatase acting on multiple sites of a substrate that, contingent on its modification state, catalyzes its own phosphorylation and, in a symmetric scenario, dephosphorylation. The symmetric case is viewed as a cartoon of conflicting feedback that could result from antagonistic pathways impinging on the state of a shared component. Results Multisite phosphorylation is sufficient for bistable behavior under feedback even when catalysis is linear in substrate concentration, which is the case we consider. We compute the phase diagram, fluctuation spectrum and large-deviation properties related to switch memory within a statistical mechanics framework. Bistability occurs as either a first-order or second-order non-equilibrium phase transition, depending on the network symmetries and the ratio of phosphatase to kinase numbers. In the second-order case, the circuit never leaves the bistable regime upon increasing the number of substrate molecules at constant kinase to phosphatase ratio. Conclusion The number of substrate molecules is a key parameter controlling both the onset of the bistable regime, fluctuation intensity, and the residence time in a switched state. The relevance of the concept of memory depends on the degree of switch symmetry, as memory presupposes information to be remembered, which is highest for equal residence times in the switched states. Reviewers This article was reviewed by Artem Novozhilov (nominated by Eugene Koonin, Sergei Maslov, and Ned Wingreen.

  7. MOSFET Switching Circuit Protects Shape Memory Alloy Actuators

    Science.gov (United States)

    Gummin, Mark A.

    2011-01-01

    A small-footprint, full surface-mount-component printed circuit board employs MOSFET (metal-oxide-semiconductor field-effect transistor) power switches to switch high currents from any input power supply from 3 to 30 V. High-force shape memory alloy (SMA) actuators generally require high current (up to 9 A at 28 V) to actuate. SMA wires (the driving element of the actuators) can be quickly overheated if power is not removed at the end of stroke, which can damage the wires. The new analog driver prevents overheating of the SMA wires in an actuator by momentarily removing power when the end limit switch is closed, thereby allowing complex control schemes to be adopted without concern for overheating. Either an integral pushbutton or microprocessor-controlled gate or control line inputs switch current to the actuator until the end switch line goes from logic high to logic low state. Power is then momentarily removed (switched off by the MOSFET). The analog driver is suited to use with nearly any SMA actuator.

  8. Technology development of RF MEMS switches on printed circuit boards

    Science.gov (United States)

    Chang, Hung-Pin

    Today, some engineers have shifted their focus on the micro-electro-mechanical system (MEMS) to pursue better technological advancements. Recent development in RF MEMS technologies have lead to superior switch characteristics, i.e., very low insertion loss, very low power requirements, and high isolation comparing to the conventional semiconductor devices. This success has promised the potential of MEMS to revolutionize RF and microwave system implementation for the next generation of communication applications. However, RF MEMS switches integrated monolithically with various RF functional components on the same substrate to create multifunctional and reconfigurable complete communication systems remains to be a challenge research topic due to the concerns of the high cost of packaging process and the high cost of RF matching requirements in module board implementation. Furthermore, the fabrication of most RF MEMS switches requires thickness control and surface planarization of wide metal lines prior to deposition of a metal membrane bridge, which poses a major challenge to manufacturability. To ease the fabrication of RF MEMS switches and to facilitate their integration with other RF components such as antennas, phase delay lines, tunable filters, it is imperative to develop a manufacturable RF MEMS switch technology on a common substrate housing all essential RF components. Development of a novel RF MEMS technology to build a RF MEMS switch and provide a system-level packaging on microwave laminated printed circuit boards (PCBs) are proposed in this dissertation. Two key processes, high-density inductively coupled plasma chemical vapor deposition (HDICP CVD) for low temperature dielectric deposition, and compressive molding planarization (COMP) for the temporary sacrificial polymer planarization have been developed for fabricating RF MEMS switches on PCBs. Several membrane-type capacitive switches have been fabricated showing excellent RF performance and dynamic

  9. Performance Analysis of Different Optical Switching Architectures

    Directory of Open Access Journals (Sweden)

    Salman A. Al-Qahtani

    2011-01-01

    Full Text Available Problem statement: Optical Packet Switching (OPS and transmission networks based on Wavelength Division Multiplexing (WDM have been increasingly deployed in the Internet infrastructure over the last decade in order to meet the huge increasing demand for bandwidth. Several different technologies have been developed for optical packet switching such as space switches, broadcast-and-select, input buffered switches and output buffered switches. These architectures vary based on several parameters such as the way of optical buffering, the placement of optical buffers, the way of solving the external blocking inherited from switching technologies in general and the components used to implement WDM. Approach: This study surveys most of the exiting optical packet switching architectures. A simulation-based comparison of input buffered and output buffered architectures were presented. Results: The performance analysis of the selected two architectures derived using simulation program and compared at different scenarios. We found that the output buffered architectures give better performance than input buffered architectures. Conclusion: The simulation results shows that the-broadcast-and-select architecture is attractive in terms that it has lees number of components compared to other switches.

  10. Switching Surge Analysis of Vacuum Circuit Breaker using EMTP

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ik Mo; Kim, Ji Hong [Hyundai Heavy Industry, Mechatronics Research Institute (Korea)

    2000-07-01

    The first objective of this study is to set up the switching surge analysis method in motor driving distribution system. The simplified model which can simulate the motor energization and circuit breaker re-ignitions, and each circuit element model is presented in this paper. The second objective is to calculate the quantity of surge over-voltage in real nuclear power station. And the surge suppressing measures are verified on the simulation basis. It is clarified that most cases are not satisfactory to meet the IEEE standard 522-1992 without using surge suppressing measures. In cases that the surge arrester are installed in distribution board at the load side of circuit breaker. The IEEE specification is fully met. (author). 6 refs., 4 figs., 3 tabs.

  11. Switched Flip-Flop based Preprocessing Circuit for ISFETs

    Directory of Open Access Journals (Sweden)

    Martin Kollár

    2005-03-01

    Full Text Available In this paper, a preprocessing circuit for ISFETs (Ion-sensitive field-effecttransistors to measure hydrogen-ion concentration in electrolyte is presented. A modifiedflip-flop is the main part of the circuit. The modification consists in replacing the standardtransistors by ISFETs and periodically switching the supply voltage on and off.Concentration of hydrogen ions to be measured discontinues the flip-flop value symmetry,which means that by switching the supply voltage on the flip-flop goes to one of two stablestates, ‘one’ or ‘zero’. The recovery of the value symmetry can be achieved by changing abalanced voltage, which is incorporated to the flip-flop, to bring the flip-flop to a 50%position (probability of ‘one’ equals to probability of ‘zero’. Thus, the balanced voltagereflects the measured concentration of hydrogen ions. Its magnitude is set automatically byusing a feedback circuit whose input is connected to the flip-flop output. The preprocessingcircuit, as the whole, is the well-known δ modulator in which the switched flip-flop servesas a comparator and a sampling circuit. The advantages of this approach in comparison tothose of standard approaches are discussed. Finally, theoretical results are verified bysimulations with TSPICE and a good agreement is reported.

  12. Optical packet switching without packet alignment

    DEFF Research Database (Denmark)

    Hansen, Peter Bukhave; Danielsen, Søren Lykke; Stubkjær, Kristian

    1998-01-01

    Operation without packet alignment of an all-optical packet switch is proposed and predicted feasible through a detailed traffic analysis. Packet alignment units are eliminated resulting in a simple switch architecture while optimal traffic performance is maintained through the flexibility provided...

  13. Isolation of Integrated Optical Acousto-Optic Switch

    Institute of Scientific and Technical Information of China (English)

    XIAO Li-Feng; LIU Ying; WANG Wei-Peng; GENG Fan

    2006-01-01

    @@ Isolation of a new structured acousto-optic switch based on an integrated optical polarization-independent quasicollinear acousto-optic tunable filter is studied in detail. The factors that influence the isolation of the optical switch are analysed, the expressions of the isolation are educed, and the isolation of the device is measured in experiment. It is found that the isolation mainly depends on the TE/TM mode intensity ratio, the mode-splitter extinction rate, and the conversion efficiency.

  14. United assembly algorithm for optical burst switching

    Institute of Scientific and Technical Information of China (English)

    Jinhui Yu(于金辉); Yijun Yang(杨教军); Yuehua Chen(陈月华); Ge Fan(范戈)

    2003-01-01

    Optical burst switching (OBS) is a promising optical switching technology. The burst assembly algorithm controls burst assembly, which significantly impacts performance of OBS network. This paper provides a new assembly algorithm, united assembly algorithm, which has more practicability than conventional algorithms. In addition, some factors impacting selections of parameters of this algorithm are discussed and the performance of this algorithm is studied by computer simulation.

  15. Reduction of Switching Surge by Controlled Shunt Reactor Switching of Gas Circuit Breaker

    Science.gov (United States)

    Kohyama, Haruhiko; Ito, Hiroki; Asai, Jun; Hidaka, Mikio; Yonezawa, Takashi

    Controlled switching system (CSS) with a 204kV gas circuit breaker (GCB) demonstrates to reduce an inrush current and to eliminate re-ignitions in shunt reactor switching. Target closing and opening instants for controlled switching are determined by the electrical and mechanical characteristics of GCB. Idle time dependence of the operating time, which gives a sufficient impact on controlling accuracy, is evaluated and successfully compensated by synchronous switching controller (SSC). Field operation of CSS for a year shows an effective suppression of inrush current on closing and prevention of re-ignitions on opening of shunt reactor. The operations also proved that the CSS has a satisfactory performance for electro-magnetic disturbance imposed in practical field.

  16. All-Optical Programmable Disaggregated Data Centre Network realized by FPGA-based Switch and Interface Card

    OpenAIRE

    Yan, Yan; Saridis, George; Shu, Yi; R. Rofoee, Bijan; Yan, Shuang Yi; Arslan, Murat; Richardson, David; Poole, Simon; Zervas, Georgios; Simeonidou, Dimitra; Bradley, Tom; Wheeler, Natalie V.; Wong, Nicholas H.L.; Poletti, Francesco; Petrovich, Marco N.

    2016-01-01

    This paper reports a FPGA-based Switch and Interface Card (SIC) and its application scenario in an all-optical, programmable disaggregated Data Centre Network (DCN). Our novel SIC is designed and implemented to replace traditional optical Network Interface Cards (NICs), plugged into the server directly, supporting Optical Packet Switching (OPS)/ Optical Circuit Switching (OCS) or Time Division Multiplexing (TDM)/ Wavelength Division Multiplexing (WDM) traffic on demand. Placing the SIC in eac...

  17. Optical switching with a thermochromic film

    Science.gov (United States)

    Men, Liqiu; Chen, Qiying

    2007-02-01

    In this article, optical switching effect of a thermochromic thin film is reported. The transmittance of the film increased from 0.64 at 120°C to 0.96 at 200°C indicating strong temperature dependence for its optical properties. The temperature dependence of the optical properties was found to be reversible during the heating and cooling processes. The possibility to reduce the size of the laser beam with the nonlinear optical switching effect of the thermochromic film is discussed.

  18. Scheduling Issues in ECOFRAME Optical Packet Switched Ring

    Directory of Open Access Journals (Sweden)

    P. Gravey

    2011-06-01

    Full Text Available In the metropolitan area, traditional SONET/SDH circuit switched rings are likely to be replaced with optical packet/burst switching technologies. In this paper we consider a slotted WDM optical packet ring operating without resource reservation mechanisms. In such rings, optical packets in transit have priority over traffic to be inserted by the node. Packets to be inserted are thus queued according to their destination, in order to avoid headof-line blocking. We focus on scheduling policies and compare several MaxWeight scheduling policies, including Oldest Packet First (OPF which emulates FIFO queueing while avoiding head-of-line blocking. We show that there is a trade-off between implementation complexity and fairness, and identify the Largest Virtual Waiting Time First (LVWTF scheduling policy as presenting both a low complexity and a good fairness performance.

  19. Multiserver switch scheduling for high speed optical switches

    Science.gov (United States)

    Golla, Prasad; Blanton, John; Damm, Gerard

    2003-10-01

    A switch matrix implemented as an optical crossbar using semiconductor optical amplifiers is able to accommodate extreme concentrations of data traffic. Due to the need to reduce optical guard band overhead it is beneficial to switch fixed size bursts of data cells on a time slot basis. The high capacity of the optical matrix supports multiple optical ports per burst card, and the implementation of multiple queue servers per burst card helps make better use of the multiplicity of ports. Problems associated with arbitrating multiple ports and multiple servers per burst card have been resolved by extending the operation of existing iterative, single server scheduling algorithms. The multiserver arbitration time will be in proportion to the number of servers -- corresponding to the channels of DWDM link -- unless a reconciliation stage is used after each iteration when an arbiter per server is used. The reconciliation stage sets the problem of broken data dependencies between server arbitrations in this case. Further, to address the time limitations for computing the scheduling solution, parallel arbiter implementations have been developed and tested against single arbiter designs. Again, the broken dependencies between iterations of an arbitration are addressed through the use of a grant reconciliation stage. The use of multiple queue servers per burst card also resolves some of the data loss problems related to polarized traffic. Simulations of the multiple server and parallel arbiter implementations have demonstrated their efficiency compared to previous implementations. Compounded to this problem is maintaining high throughput of the switch matrix while observing data transit time limits. This involves balancing two contradictory requirements; switch or line card efficiency and data transit times. To improve efficiency it is desirable to transmit only full packets. However, to prevent loss of data due to timeout it will be necessary to transmit some incomplete

  20. Experimental Demonstration of 7 Tb/s Switching Using Novel Silicon Photonic Integrated Circuit

    DEFF Research Database (Denmark)

    Ding, Yunhong; Kamchevska, Valerija; Dalgaard, Kjeld;

    2016-01-01

    We demonstrate BER performance <10^-9 for a 1 Tb/s/core transmission over 7-core fiber and SDM switching using a novel silicon photonic integrated circuit composed of a 7x7 fiber switch and low loss SDM couplers.......We demonstrate BER performance integrated circuit composed of a 7x7 fiber switch and low loss SDM couplers....

  1. Vertically Integrated Thermo-Optic Waveguide Switch Using Optical Polymers

    Institute of Scientific and Technical Information of China (English)

    Ki-Hong Kim; Sang-Yung Shin; Doo-Sun Choi

    2003-01-01

    We propose and fabricate a vertically integrated thermo-optic waveguide switch. It controls the optical path between two vertically stacked waveguides using the thermo-optic effect of optical polymer. The measured crosstalk is less than-10 dB.

  2. Vertically Integrated Thermo-Optic Waveguide Switch Using Optical Polymers

    Institute of Scientific and Technical Information of China (English)

    Ki-Hong; Kim; Sang-Yung; Shin; Doo-Sun; Choi

    2003-01-01

    We propose and fabricate a vertically integrated thermo-optic waveguide switch. It controls the optical path between two vertically stacked waveguides using the thermo-optic effect of optical polymer. The measured crosstalk is less than -10 dB.

  3. 160-Gb/s Silicon All-Optical Packet Switch for Buffer-less Optical Burst Switching

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Pu, Minhao;

    2015-01-01

    We experimentally demonstrate a 160-Gb/s Ethernet packet switch using an 8.6-mm-long silicon nanowire for optical burst switching, based on cross phase modulation in silicon. One of the four packets at the bit rate of 160 Gb/s is switched by an optical control signal using a silicon based 1 × 1 all......-optical packet switch. Error free performance (BER <1E-9) is achieved for the switched packet. The use of optical burst switching protocols could eliminate the need for optical buffering in silicon packet switch based optical burst switching, which might be desirable for high-speed interconnects within a short...

  4. Self power generating piezoelectric elements applied to switching circuits

    International Nuclear Information System (INIS)

    In this study, we focused on lead zirconate titanate (PZT) as a power generating piezoelectric element. Niobium was added to each of the PZT elements to improve their power generation characteristics. The purpose of the study was to develop a high-efficiency PZT generator element that utilizes the vibration loads in the support members of a structure. We have previously reported the power generation characteristics of laminated PZT elements under vibration loads. Effect of vibration load, vibration frequency and number of PZT layers on generation characteristics of PZT elements was evaluated in the vibration test. We evaluate the power generation of laminated PZT elements and present the results of an experiment using a switching circuit as a load circuit in order to confirm the suitability of the laminated PZT element as a power source

  5. Switching regulator emission control circuit for ion sources

    Science.gov (United States)

    Clay, F. P., Jr.; Brock, F. J.; Melfi, L. T., Jr.

    1975-01-01

    An electron emission control circuit of the switching regulator type operating at 100 kHz has been developed which maintains a constant emission current within 0.1% for a cathode power demand variation of approximately 100%. The power output stage has an efficiency of 67%, and the overall efficiency is 45% when driving a thoria-coated iridium cathode having a nominal resistance at operating temperature of 2.5 ohms. Under optimum conditions, the bus power demand is 1.75 W. The circuit is useful in controlling the electron emission current of ion sources in applications which involve a substantial variation of the cathode work function, such as oxygen partial pressure measurements over a large dynamic range.

  6. Combining SDM-Based Circuit Switching with Packet Switching in a Router for On-Chip Networks

    OpenAIRE

    Angelo Kuti Lusala; Jean-Didier Legat

    2012-01-01

    A Hybrid router architecture for Networks-on-Chip “NoC” is presented, it combines Spatial Division Multiplexing “SDM” based circuit switching and packet switching in order to efficiently and separately handle both streaming and best-effort traffic generated in real-time applications. Furthermore the SDM technique is combined with Time Division Multiplexing “TDM” technique in the circuit switching part in order to increase path diversity, thus improving throughput while sharing communication r...

  7. All-optical switching in optically induced nonlinear waveguide couplers

    Energy Technology Data Exchange (ETDEWEB)

    Diebel, Falko, E-mail: falko.diebel@uni-muenster.de; Boguslawski, Martin; Rose, Patrick; Denz, Cornelia [Institut für Angewandte Physik and Center for Nonlinear Science (CeNoS), Westfälische Wilhelms-Universität Münster, 48149 Münster (Germany); Leykam, Daniel; Desyatnikov, Anton S. [Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)

    2014-06-30

    We experimentally demonstrate all-optical vortex switching in nonlinear coupled waveguide arrays optically induced in photorefractive media. Our technique is based on multiplexing of nondiffracting Bessel beams to induce various types of waveguide configurations. Using double- and quadruple-well potentials, we demonstrate precise control over the coupling strength between waveguides, the linear and nonlinear dynamics and symmetry-breaking bifurcations of guided light, and a power-controlled optical vortex switch.

  8. All-optical active switching in individual semiconductor nanowires

    Science.gov (United States)

    Piccione, Brian; Cho, Chang-Hee; van Vugt, Lambert K.; Agarwal, Ritesh

    2012-10-01

    The imminent limitations of electronic integrated circuits are stimulating intense activity in the area of nanophotonics for the development of on-chip optical components, and solutions incorporating direct-bandgap semiconductors are important in achieving this end. Optical processing of data at the nanometre scale is promising for circumventing these limitations, but requires the development of a toolbox of components including emitters, detectors, modulators, waveguides and switches. In comparison to components fabricated using top-down methods, semiconductor nanowires offer superior surface properties and stronger optical confinement. They are therefore ideal candidates for nanoscale optical network components, as well as model systems for understanding optical confinement. Here, we demonstrate all-optical switching in individual CdS nanowire cavities with subwavelength dimensions through stimulated polariton scattering, as well as a functional NAND gate built from multiple switches. The device design exploits the strong light-matter coupling present in these nanowires, leading to footprints that are a fraction of those of comparable silicon-based dielectric contrast and photonic crystal devices.

  9. Electronic circuits and systems: A compilation. [including integrated circuits, logic circuits, varactor diode circuits, low pass filters, and optical equipment circuits

    Science.gov (United States)

    1975-01-01

    Technological information is presented electronic circuits and systems which have potential utility outside the aerospace community. Topics discussed include circuit components such as filters, converters, and integrators, circuits designed for use with specific equipment or systems, and circuits designed primarily for use with optical equipment or displays.

  10. Simplified overflow analysis of an optical burst switch with fibre delay lines

    OpenAIRE

    McArdle, Conor; Tafani, Daniele; Liam P. Barry; Holohan, Anthony; Curran, Thomas

    2009-01-01

    We develop an approximate analytic model of an Optical Burst Switch with share-per-node fibre delay lines and tuneable wavelength converters by employing Equivalent Random Theory, an approach from circuit-switching analysis. Our model is formulated in terms of virtual traffic flows within the switch from which we derive expressions for burst blocking probability, fibre delay line occupancy and mean delay, which we then resolve numerically. Emphasis is on simplicity of the model to achieve goo...

  11. SDN architecture for optical packet and circuit integrated networks

    Science.gov (United States)

    Furukawa, Hideaki; Miyazawa, Takaya

    2016-02-01

    We have been developing an optical packet and circuit integrated (OPCI) network, which realizes dynamic optical path, high-density packet multiplexing, and flexible wavelength resource allocation. In the OPCI networks, a best-effort service and a QoS-guaranteed service are provided by employing optical packet switching (OPS) and optical circuit switching (OCS) respectively, and users can select these services. Different wavelength resources are assigned for OPS and OCS links, and the amount of their wavelength resources are dynamically changed in accordance with the service usage conditions. To apply OPCI networks into wide-area (core/metro) networks, we have developed an OPCI node with a distributed control mechanism. Moreover, our OPCI node works with a centralized control mechanism as well as a distributed one. It is therefore possible to realize SDN-based OPCI networks, where resource requests and a centralized configuration are carried out. In this paper, we show our SDN architecture for an OPS system that configures mapping tables between IP addresses and optical packet addresses and switching tables according to the requests from multiple users via a web interface. While OpenFlow-based centralized control protocol is coming into widespread use especially for single-administrative, small-area (LAN/data-center) networks. Here, we also show an interworking mechanism between OpenFlow-based networks (OFNs) and the OPCI network for constructing a wide-area network, and a control method of wavelength resource selection to automatically transfer diversified flows from OFNs to the OPCI network.

  12. 2-18 GHz broadband MMIC SPDT switches based on GMIC and heterolithic circuits

    OpenAIRE

    Howell, Charles M.; Regan, John J.

    1990-01-01

    Monolithic integrated circuit switches can be fabricated using either GaAs FETs or with PIN diodes as the active elements. Each offers advantages and disadvantages to the circuit design. It has been shown that because of their higher switching Q1,4 that PIN diodes should exhibit lower loss and higher isolation in the same circuit than a switch made with a FET as the switching element. Conversely, FET based switches offer an advantage of less control power and better DC to RF isolation of the ...

  13. Devices for wavelength switching in optical networks

    Energy Technology Data Exchange (ETDEWEB)

    d`Alessandro, A.; Baran, J.E. [Bellcore, Red Bank, NJ (United States); Smith, D.A. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Electrical Engineering and Applied Physics

    1994-12-31

    Wavelength routing crossconnects are considered the core of WDM optical networks. They consist of optical switches independently rearrangeable for each wavelength channel and for any input-output configuration so that any path can be chosen almost arbitrarily by the network users. In general the implementation of the wavelength routing function requires complex switch arrays. Very simple wavelength-selection crossconnects can be realized by using acousto-optic switches (AOS), because of their unique ability of processing several optical signals simultaneously and their low driving power consumption, less than 10 mW/channel. AOS`s can be considered a particular evolution of acousto-optical tunable filters, whose integrated optic version on lithium niobate has been developed in several research institutions around the world in the past decade. This paper reviews the last accomplishments of AOS`s, whose specifications are directly tied with optical network requirements, the foremost challenge being a strong suppression of crosstalk. Dilated AOS`s can reduce interport crosstalk to below {minus}30 dB and apodization of acousto-optic interaction can reduce interchannel crosstalk to below {minus}15 dB during multiwavelength operation.

  14. Alternative Controller for a Fiber-Optic Switch

    Science.gov (United States)

    Peters, Robert

    2007-01-01

    A simplified diagram of a relatively inexpensive controller for a DiCon VX (or equivalent) fiber-optic switch -- an electromechanically actuated switch for optically connecting one or two input optical fibers to any of a number of output optical fibers is shown. DiCon VX fiber-optic switches are used primarily in research and development in the telecommunication industry. This controller can control any such switch having up to 32 output channels.

  15. Nonlinear optics quantum computing with circuit QED.

    Science.gov (United States)

    Adhikari, Prabin; Hafezi, Mohammad; Taylor, J M

    2013-02-01

    One approach to quantum information processing is to use photons as quantum bits and rely on linear optical elements for most operations. However, some optical nonlinearity is necessary to enable universal quantum computing. Here, we suggest a circuit-QED approach to nonlinear optics quantum computing in the microwave regime, including a deterministic two-photon phase gate. Our specific example uses a hybrid quantum system comprising a LC resonator coupled to a superconducting flux qubit to implement a nonlinear coupling. Compared to the self-Kerr nonlinearity, we find that our approach has improved tolerance to noise in the qubit while maintaining fast operation.

  16. Node design in optical packet switched networks

    OpenAIRE

    Nord, Martin; Dittmann, Lars

    2006-01-01

    The thesis discusses motivation, realisation and performance of the Optical Packet Switching (OPS) network paradigm. The work includes proposals for designs and methods to efficiently use both the wavelength- and time domain for contention resolution in asynchronous operation. The project has also proposed parallel designs to overcome scalability constraints and to support migration scenarios. Furthermore, it has proposed and demonstrated optical input processing schemes for hybrids networks ...

  17. Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit

    OpenAIRE

    Dudrik, Jaroslav; BODOR Marcel; TRIP Daniel Nistor

    2010-01-01

    Auxiliary circuit for DC/DC converter withcontrolled output rectifier is presented in this paper.Soft switching for power switches of the inverter isachieved by using controlled output rectifier and softswitching of the controlled rectifier by using losslessauxiliary circuit. The principle of converter operationis explained and analyzed and experimental results onthe laboratory model are presented.

  18. Switching circuit to improve the frequency modulation difference-intensity THz quantum cascade laser imaging

    International Nuclear Information System (INIS)

    We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modulation up to ∼100 Hz

  19. Switching circuit to improve the frequency modulation difference-intensity THz quantum cascade laser imaging

    OpenAIRE

    Saat, NK; Dean, P.; Khanna, SP; Salih, M; Linfield, EH; Davies, AG

    2015-01-01

    We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modula...

  20. Photonic Packet Switching Based on Optical Label Processing

    Institute of Scientific and Technical Information of China (English)

    Naoya Wada; Hiroaki Harai; Fumito Kubota

    2003-01-01

    We express a photonic packet switch prototype based on optical label processing methods which dramatically increase the label processing capability. We experimentally demonstrate 40Gbit/s/port packet switching and optical buffering capabilities of the prototype.

  1. Evaluation of laser diode based optical switches for optical processors

    Science.gov (United States)

    Swanson, Paul D.; Parker, Michael A.; Libby, Stuart I.

    1993-07-01

    Three optical switching elements have been designed, fabricated, and tested for use in an integrated, optical signal processor. The first, an optical NOR logic gate, uses gain quenching as a means of allowing one (or more) light beam(s) to control the output light. This technique, along with the use of a two pad bistable output laser, is used in demonstrating the feasibility of the second device, an all optical RS flip flop. The third device consists of a broad area orthogonal model switching laser, whose corollary outputs correspond to the sign of the voltage difference between its two high impedance electrical inputs. This device also has possible memory applications if bistable mode switching within the broad area laser can be achieved.

  2. HSPICE modelling of a solar array circuit controlled by a fet switch

    Science.gov (United States)

    Cox, Deanna D.; Natarajan, T.; Day, John

    1987-01-01

    This paper presents a method of modeling a solar array circuit controlled by a hexfet switch on HSPICE. HSPICE models are developed for the solar array current voltage (IV) characteristic and the IRF150 hexfet. Computer simulations are made to verify rate of current change at the load. The equivalent LC circuit for the same current control is modeled to show savings in weight and power in choosing the fet switch over an LC circuit.

  3. Design and Simulation of Routing-switching Protocol Based on Optical Switch Array

    Institute of Scientific and Technical Information of China (English)

    HE Wei; MAO You-ju; LIU Jiang

    2004-01-01

    An optical routing- switching technology based on optical switch array is proposed. The characteristics of the blocking and nonblocking networks are analyzed and compared, odd- even sorting network is used to realize optical routing- switching, relative routing- switching protocol is designed.Simulation test under load shows that it can reduce a blocking effectively and enhance an efficiency of switching. Further, it can transfer the processing and switching within parallel computer from electric domain to optical domain. It can make parallel computer coordinating computing and processing at much more higher speed, storing and transmitting even more efficiently.

  4. Research of high speed optical switch based on compound semiconductor

    Institute of Scientific and Technical Information of China (English)

    WANG MingHua; QI Wei; YU Hui; JIANG XiaoQing; YANG JianYi

    2009-01-01

    High-speed optical switch and its array are the crucial components of all-optical switching system. This paper presents the analytical model of a total-internal-reflection (TIR) optical switch. By employing the carrier injection effect in GaAs and the GaAs/AlGaAs double heterojunction structure, the X-junction TIR switch and the Mach-Zehnder interference (MZI) switch are demonstrated at 1.55 IJm. The measured results show that the extinction ratio of both switches exceeds 20 dB. The switching speed reaches the scale of 10 ns.

  5. Two Novel Structures of Optical Packet Switching Nodes

    Institute of Scientific and Technical Information of China (English)

    YIN Hongxi; XU Anshi; WU Deming

    2001-01-01

    All-optical packet switching networkis currently one of the research hotspots of all-opticalcommunication networks and optical packet switchingnodes are the key technique of optical packet switch-ing network. In this paper, two novel structures ofoptical packet switching nodes are put forward, and the switching capacity of the node and the packet con-tention resolution are analyzed. These two switchingarchitectures can realize wavelength routing switchingfunction and broadcast-and-select switching functionrespectively. They are simple but efficient for realizingoptical packet switching network.

  6. 49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.

    Science.gov (United States)

    2010-10-01

    ... circuits through circuit controller. 236.13 Section 236.13 Transportation Other Regulations Relating to...; selection of signal control circuits through circuit controller. The control circuits of signals governing... circuit controller, or through the contacts of relay repeating the position of such circuit...

  7. High-speed multichannel optical switching

    Energy Technology Data Exchange (ETDEWEB)

    Mikaelian, A.L.; Salakhutdinov, V.K. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Optical Neural Technologies

    1994-12-31

    The programmable interconnection between N input and N output channels based on a matrix of microholograms is considered. Such a system can be used for optical switching having high speed, about gigabits-per-second. An example of such a system using bacteriorhodopsin film is investigated both theoretically and experimentally. The thickness of bacteriorhodopsin was 50 {micro}m and the cell size 3cmx2cm. To maintain interconnects each microhologram was regenerated by means of a routing system composed of a He-Ne laser, deflectors and optical elements. Experimentally, 20 channels were used. The diameter of the microhologram was 1 mm, and the diffraction efficiency was about 2%. The tests and calculations show the possibility of arranging 10{sup 4} switching channels with speed about 1 gigabit per second.

  8. A Novel Crowbar Impulse Current Circuit for Testing the Switch-Type SPD

    Institute of Scientific and Technical Information of China (English)

    YAO Xueling; CHEN Jingliang; SUN Wei

    2008-01-01

    A crowbar impulse current circuit for testing the switch-type surge protective device (SPD) is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseudospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface flashover trigger device made of high relative perimittivity dielectric material BaTiO3 (εr = 3460), the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current wave form of maximum 25 kA was generated with a rise time and time to half peak value of 17.2/μs and 336 μs respectively.

  9. Simple modeling for conducted common-mode current in switching circuits

    OpenAIRE

    Kchikach, M; Yuan, YS; Qian, ZM; Pong, MH

    2001-01-01

    Common mode current strongly depends on stray capacitance of each circuit node, especially those with high dv/dt and di/dt. To build a simple model for conducted common mode current in switching circuit a computer software based on Partial Element Equivalent Circuit (PEEC) method is used to calculate the parasitic elements of the printed circuit board (PCB). Simulation results agree well with experimental results up to 10 MHz.

  10. A Novel PFC Circuit for Three-Phase Utilizing Single Switching Device

    OpenAIRE

    Matsui, Keiju; Hasegawa, Masaru

    2010-01-01

    An improved circuit strategy has been proposed and discussed, based on an extension of the Prasad-Ziogas circuit, offering significant improvement in the THD characteristic. The results have been presented and compared. The proposed circuit uses single switching device like the conventional one and the characteristics can be improved sufficiently by using a simple auxiliary capacitor connection. In this way, a three phase PFC circuit can be realized in a simple manner. Another feature in the ...

  11. Application of magnetic switch for commutation of heavy-current pulsed circuits

    International Nuclear Information System (INIS)

    One studied commutation of heavy-current pulsed circuits with application of a magnetic switch - inductance coil coiled round a toroidal ferromagnetic core. Application of the magnetic switch enables to use simpler and more reliable two-electrode dischargers actuated by high-volt initiating pulse. The switch nonlinear inductance serves for decoupling of heavy-current electric circuit and low-current circuit of initiation. Device was tested at commutation of up to 100 kJ energy and pulse millisecond duration capacitance accumulator discharge

  12. Combining SDM-Based Circuit Switching with Packet Switching in a Router for On-Chip Networks

    Directory of Open Access Journals (Sweden)

    Angelo Kuti Lusala

    2012-01-01

    Full Text Available A Hybrid router architecture for Networks-on-Chip “NoC” is presented, it combines Spatial Division Multiplexing “SDM” based circuit switching and packet switching in order to efficiently and separately handle both streaming and best-effort traffic generated in real-time applications. Furthermore the SDM technique is combined with Time Division Multiplexing “TDM” technique in the circuit switching part in order to increase path diversity, thus improving throughput while sharing communication resources among multiple connections. Combining these two techniques allows mitigating the poor resource usage inherent to circuit switching. In this way Quality of Service “QoS” is easily provided for the streaming traffic through the circuit-switched sub-router while the packet-switched sub-router handles best-effort traffic. The proposed hybrid router architectures were synthesized, placed and routed on an FPGA. Results show that a practicable Network-on-Chip “NoC” can be built using the proposed router architectures. 7 × 7 mesh NoCs were simulated in SystemC. Simulation results show that the probability of establishing paths through the NoC increases with the number of sub-channels and has its highest value when combining SDM with TDM, thereby significantly reducing contention in the NoC.

  13. Ultimate-fast all-optical switching of a microcavity

    NARCIS (Netherlands)

    Yuce, E.

    2013-01-01

    In this thesis we study ultrafast all-optical switching of microcavities. We employ the electronic Kerr effect to switch the resonance frequency of microcavities operating at telecom wavelengths. We observe the fastest possible switching of a microcavity resonance within 300 fs. The switching speed

  14. An all-optical matrix multiplication scheme with non-linear material based switching system

    Institute of Scientific and Technical Information of China (English)

    Archan Kumar Das; Sourangshu Mukhopadhyay

    2005-01-01

    Optics is a potential candidate in information, data, and image processing. In all-optical data and information processing, optics has been used as information carrying signal because of its inherent advantages of parallelism. Several optical methods are proposed in support of the above processing. In many algebraic,arithmetic, and image processing schemes fundamental logic and memory operations are conducted exploring all-optical devices. In this communication we report an all-optical matrix multiplication operation with non-linear material based switching circuit.

  15. Submicrosecond rearrangeable nonblocking silicon-on-insulator thermo-optic 4x4 switch matrix.

    Science.gov (United States)

    Li, Yuntao; Yu, Jinzhong; Chen, Shaowu; Li, Yanping; Chen, Yuanyuan

    2007-03-15

    A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4x4 switch matrix is designed and fabricated. A spot-size converter is integrated to reduce the insertion loss, and a new driving circuit is designed to improve the response speed. The insertion loss is less than 10 dB, and the response time is 950 ns. PMID:17308574

  16. Compact integrated optical devices for optical sensor and switching applications

    NARCIS (Netherlands)

    Kauppinen, Lasse Juhana

    2010-01-01

    This thesis describes the design, fabrication, and characterization of compact optical devices for sensing and switching applications. Our focus has been to realize the devices using CMOS-compatible fabrication processes. Particularly the silicon photonics fabrication platform, ePIXfab, has been use

  17. Optical switch based on nanocrystalline VOx thin film

    Science.gov (United States)

    Chen, Xiqu; Dai, Jun

    2009-11-01

    An optical switch is fabricated based on nanocrystalline vanadium oxide (VOx) thin film using micromachining technology. An "on" state with semiconducting phase to an "off" state with metallic phase is controlled by applying a DC power to Aurum electrodes of the optical switch. The optical switching performance for the fabricated device is investigated at optical communication wavelength of 1.55μm. The heater power requires to achieve switching action is about 15mW. The testing results show that the extinction ratio and switching response time are 14dB and 2ms, respectively.

  18. Chip-scale fully reconfigurable optical add/drop multiplexing subsystem in polymer microphotonic circuits

    Science.gov (United States)

    Izuhara, Tomoyuki; Fujita, Junichiro; Radojevic, Antonije; Gerhardt, Reinald; Eldada, Louay A.

    2004-10-01

    We report on a highly integrated photonic circuit using a polymer-based planar waveguide system. The properties of the materials used in this work such as ultra-low optical loss, widely tunable refractive index, and large thermo-optic coefficient, enable a multi-functional chip-scale microphotonic circuit. We discuss the application of this technology to the fabrication of a fully reconfigurable optical add/drop multiplexer. This subsystem includes channel switching, power monitoring, load balancing, and wavelength shuffling functionalities that are required for agile wavelength-division multiplexing optical networks. Optical properties of our material systems and performance characteristics of the implemented optical passive/active elements are presented, and the integration schemes of the devices to achieve a fully integrated reconfigurable optical add/drop multiplexer are discussed.

  19. Integrated optoelectronic materials and circuits for optical interconnects

    International Nuclear Information System (INIS)

    Conventional interconnect and switching technology is rapidly becoming a critical issue in the realization of systems using high speed silicon and GaAs based technologies. In recent years clock speeds and on-chip density for VLSI/VHSIC technology has made packaging these high speed chips extremely difficult. A strong case can be made for using optical interconnects for on-chip/on-wafer, chip-to-chip and board-to-board high speed communications. GaAs integrated optoelectronic circuits (IOC's) are being developed in a number of laboratories for performing Input/Output functions at all levels. In this paper integrated optoelectronic materials, electronics and optoelectronic devices are presented. IOC's are examined from the standpoint of what it takes to fabricate the devices and what performance can be expected

  20. Optical vortex beam based optical fan for high-precision optical measurements and optical switching.

    Science.gov (United States)

    Zhou, Zhi-Yuan; Li, Yan; Ding, Dong-Sheng; Zhang, Wei; Shi, Shuai; Shi, Bao-Sen

    2014-09-01

    The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high-precision optical measurements and high-capacity and high-speed optical communications. Here we show a method for the construction of a simple and robust scheme to rotate a light beam such as a fan, which is based on a combination of these two properties and using the thermal-dispersion and electro-optical effect of birefringent crystals. Using a computer-based digital image-processing technique, we determine the temperature and thermal-dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science, and optical communication networks. PMID:25166083

  1. Optimal on/off scheme for all-optical switching

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Heuck, Mikkel; Mørk, Jesper

    2012-01-01

    We present a two-pulsed on/off scheme based on coherent control for fast switching of the optical energy in a micro cavity and use calculus of variations to optimize the switching in terms of energy.......We present a two-pulsed on/off scheme based on coherent control for fast switching of the optical energy in a micro cavity and use calculus of variations to optimize the switching in terms of energy....

  2. Model GC1312S Multifunction Integrated Optical Circuit Devices

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Model GC1312S multifunction integrated optical circuit device (MIOC) used in inertial-grade interferometric fiber optics gyroscopes (IFOGs) is fabricated by annealing and proton exchange process (APE). The unique feature of the device is the incorporation of the beat detection circuit besides all the features the conventional single Y-branch multifunction integrated optical circuit devices have. The device structure, operation principle and typical characteristics, etc., are briefly presented in this paper.

  3. All-optical devices for ultrafast packet switching

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; HerreraDorren, J.; Raz, O.;

    2007-01-01

    We discuss integrated devices for all-optical packet switching. We focus on monolithically integrated all-optical flip-flops, ultra-fast semiconductor based wavelength converters and explain the operation principles. Finally, a 160 Gb/s all-optical packet switching experiment over 110 km of field...

  4. A low-power circuit for piezoelectric vibration control by synchronized switching on voltage sources

    OpenAIRE

    Shen, Hui; Qiu, Jinhao; Ji, Hongli; Zhu, Kongjun; Balsi, Marco; Giorgio, Ivan; Dell'Isola, Francesco

    2010-01-01

    In the paper, a vibration damping system powered by harvested energy with implementation of the so-called SSDV (synchronized switch damping on voltage source) technique is designed and investigated. In the semi-passive approach, the piezoelectric element is intermittently switched from open-circuit to specific impedance synchronously with the structural vibration. Due to this switching procedure, a phase difference appears between the strain induced by vibration and the resulting voltage, thu...

  5. Performance and cost analysis of all-optical switching: OBS and OCS

    OpenAIRE

    Ekularn Dhavarudha; Chalie Charoenlarpnopparut; Suwan Runggeratigul

    2011-01-01

    This paper presents a study of performance and cost analysis of optical circuit switching (OCS) and optical burstswitching (OBS) by proposing the clear images of their node architectures and cost formulations. Then, we apply servicelevel agreement (SLA) of the high quality of service application in the terms of network blocking probability and averagenetwork delay to demonstrate OCS and OBS performances, their investment costs, and network dimensioning methodology.Applying SLA to our studies ...

  6. Nanofiber-based all-optical switches

    CERN Document Server

    Kien, Fam Le

    2016-01-01

    We study all-optical switches operating on a single four-level atom with the $N$-type transition configuration in a two-mode nanofiber cavity with a significant length (on the order of $20$ mm) and a moderate finesse (on the order of 300) under the electromagnetically induced transparency (EIT) conditions. In our model, the gate and probe fields are the quantum nanofiber-cavity fields excited by weak classical light pulses, and the parameters of the $D_2$ line of atomic cesium are used. We examine two different switching schemes. The first scheme is based on the effect of the presence of a photon in the gate mode on the EIT of the probe mode. The second scheme is based on the use of EIT to store a photon of the gate mode in the population of an appropriate atomic level, which leads to the reduction of the transmission of the field in the probe mode. We investigate the dependencies of the switching contrast on various parameters, such as the cavity length, the mirror reflectivity, and the detunings and powers ...

  7. A New Gate Drive Circuit for MOSFETs Switching at Low Frequency

    OpenAIRE

    Prakash, Narayana SR; Iyengar, BSR; Mohan, Ananda PV

    1991-01-01

    A new gate drive circuit, with ferrite core transformer isolation, for power MOSFETs switching at low frequency in the macro Hertz range has been presented . The technique involves periodic refreshing of charge on the effective gate source capacitance of the MOSFET in order to ensure low ON-state resistance,,$R_{DS}$ (ON ), by maintaining its gate source voltage above the threshold level.The simulation of the drive circuit using circuit analysis program PSPICE is described with results ...

  8. A series resonant switching charging circuit for kicker modulator and its simulation study

    International Nuclear Information System (INIS)

    A novel high voltage charging circuit specially designed for the prototype kicker modulator of the Hefei Light Source storage ring was presented. Zero-current series resonant switching techniques and a simple charging voltage control scheme was adopted in the circuit. Simulation model was established to study the performance of the circuit with a high voltage capacitor load. Designed charging voltage stability and repetition rate can be achieved through simulation analysis. Methods to increase the repetition rate are discussed

  9. A Modular, IGBT Driven, Ignitron Switched, Optically Controlled Power Supply

    Science.gov (United States)

    Carroll, Evan; von der Linden, Jens; You, Setthivoine

    2013-10-01

    An experiment to investigate the dynamics of canonical flux tubes at the University of Washington uses two high energy pulsed power supplies to generate and sustain the plasma discharge. A modular 240 μF , 12 kV DC capacitor based power supply, discharged by ignitron, has been developed specifically for this application. Design considerations include minimizing inductance, rapid switching, fast rise times, and electrically isolated control. An optically coupled front panel and fast IGBT ignitron drive circuit, sequenced manually or by software, control the charge and discharge of the power supply. A complete, sequenced charge/discharge has been successfully tested with a dummy load, producing a peak current of 100 kA and a rise time of 25 μs . This work was sponsored in part by the US DOE Grant DE-SC0010340.

  10. Beam steering by computer generated hologram for optical switches

    Science.gov (United States)

    Yamaguchi, Keita; Suzuki, Kenya; Yamaguchi, Joji

    2016-02-01

    We describe a computer generated hologram (CGH) method for application to a multiple input and multiple output (MxN) optical switch based on a liquid crystal on silicon (LCOS). The conventional MxN optical switch needs multiple spatial light modulations. However, the CGH method realizes an MxN optical switch simply with a one-time spatial light modulation, resulting in fewer optical elements and better cost efficiency. Moreover, the intrinsic loss of the proposed MxN switch resulting from beam splitting can be reduced by routing multiple signals with a single knob control, which is called a multi-pole multi-throw switch. In this paper, we demonstrate a 5x5 wavelength selective switch (WSS) and a 2-degree ROADM that we realized using the above CGH method. The experimental results indicate that these switches work well with a crosstalk of < -14.9 dB.

  11. Study of spark gap switch for crowbar circuit

    International Nuclear Information System (INIS)

    A compact and low cost 3-electrode spark gap switch, SAMTECH PCS (T)-01, was tested in considering its use as a crowbar switch of the high voltage DC power supply for ILC (International Linear Collider) modulating anode klystron. The result showed an expected performance, but its life time was shorter than we expected. Further R and D is under way. (author)

  12. Characterization of optical quantum circuits using resonant phase shifts

    CERN Document Server

    Poot, Menno

    2016-01-01

    We demonstrate that important information about linear optical circuits can be obtained through the phase shift induced by integrated optical resonators. As a proof of principle, the phase of an unbalanced Mach-Zehnder interferometer is determined. Then the method is applied to a complex optical circuit designed for linear optical quantum computation. In this controlled-NOT gate with qubit initialization and tomography stages, the relative phases are determined as well as the coupling ratios of its directional couplers.

  13. A low-power circuit for piezoelectric vibration control by synchronized switching on voltage sources

    CERN Document Server

    Shen, Hui; Ji, Hongli; Zhu, Kongjun; Balsi, Marco; Giorgio, Ivan; dell'Isola, Francesco

    2010-01-01

    In the paper, a vibration damping system powered by harvested energy with implementation of the so-called SSDV (synchronized switch damping on voltage source) technique is designed and investigated. In the semi-passive approach, the piezoelectric element is intermittently switched from open-circuit to specific impedance synchronously with the structural vibration. Due to this switching procedure, a phase difference appears between the strain induced by vibration and the resulting voltage, thus creating energy dissipation. By supplying the energy collected from the piezoelectric materials to the switching circuit, a new low-power device using the SSDV technique is proposed. Compared with the original self-powered SSDI (synchronized switch damping on inductor), such a device can significantly improve its performance of vibration control. Its effectiveness in the single-mode resonant damping of a composite beam is validated by the experimental results.

  14. Electro-optical channel drop switching in a photonic crystal waveguide-cavity side-coupling system

    Science.gov (United States)

    Chang, Kao-Der; Liu, Cheng-Yang

    2014-04-01

    The electro-optical channel drop switching in a photonic crystal waveguide-cavity side-coupling system is reported. The line waveguide is formed by removing a single row of dielectric cylinders. The twin optical microcavities side coupled between linear waveguides is studied by solving Maxwell's equations. We determine the general characteristics of the coupling element required to achieve channel drop tunneling. By modulating the conductance of the twin microcavities, the electrical tunability of the resonant modes is observed in the transmission spectrum. The spectral characteristics suggest a potential application for this switching device as an efficient multichannel optical switch in the photonic integrated circuits.

  15. Electro-optical resonant switching in two-dimensional side-coupled waveguide-cavity photonic crystal systems

    International Nuclear Information System (INIS)

    Photonic crystals have many potential applications because of their ability to control lightwave propagation. We have investigated the electro-optical resonant switching in two-dimensional photonic crystal structures. The optical microcavity side coupled with a waveguide composed of a dielectric cylinder in air is studied by solving Maxwell's equations using the plane wave expansion method and finite-difference time-domain method. The switching mechanism is a change in the conductance of the microcavity and hence modulating the resonant mode and eventually resonant switching is achieved. Such a mechanism of switching should open up a new application for designing components in photonic integrated circuits. -- Highlights: → We report the electro-optical resonant switching in 2-D photonic crystal structures. → The defect modes are made by reducing the radius of a single rod in the microcavity. → The switching mechanism is a change in the conductance of the microcavity.

  16. Design of multimode interference optical switches with area modulation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the self-imaging effect, multimode interference (MMI) optical switches with area modulation were proposed. The field transfer matrix was introduced to analyze the MMI switches. As an example, the phase modulation parameters of a 3 × 3 MMI switch for different switching cases were obtained by solving the field transfer equation. And the finite-difference beam propagation method (FD-BPM) was used to confirm the analytical results.

  17. Molecular circuits, biological switches, and nonlinear dose-response relationships.

    OpenAIRE

    Andersen, Melvin E.; Yang, Raymond S.H.; French, C. Tenley; Chubb, Laura S; Dennison, James E

    2002-01-01

    Signaling motifs (nuclear transcriptional receptors, kinase/phosphatase cascades, G-coupled protein receptors, etc.) have composite dose-response behaviors in relation to concentrations of protein receptors and endogenous signaling molecules. "Molecular circuits" include the biological components and their interactions that comprise the workings of these signaling motifs. Many of these molecular circuits have nonlinear dose-response behaviors for endogenous ligands and for exogenous toxicants...

  18. A Simple Performance Analysis of a Core Node in an Optical Burst Switched Network

    CERN Document Server

    Morsy, Mohamed H S; Shalaby, Hossam M H

    2008-01-01

    A simple mathematical model that considers the performance of an intermediate node having wavelength conversion capability in an OBS network is presented in this paper. The model assumes that the node has variable wavelength conversion capability which means that the node may have no, partial or full conversion capability. Two performance measures are derived from the model; namely, the steady state throughput and the average burst loss probability assuming Poisson traffic arrivals. In addition, a simulation work is performed in order to validate the results of our proposed model. Optimum values for the wavelength conversion capability in the node, which lead to minimum burst loss probability, are reached for different traffic conditions. Keywords: Optical Burst Switching (OBS), Optical Circuit Switching (OCS), Optical Packet Switching (OPS), Just-In-Time (JIT), Just-Enough-Time (JET).

  19. CHEETAH: circuit-switched high-speed end-to-end transport architecture

    Science.gov (United States)

    Veeraraghavan, Malathi; Zheng, Xuan; Lee, Hyuk; Gardner, M.; Feng, Wuchun

    2003-10-01

    Leveraging the dominance of Ethernet in LANs and SONET/SDH in MANs and WANs, we propose a service called CHEETAH (Circuit-switched High-speed End-to-End Transport ArcHitecture). The service concept is to provide end hosts with high-speed, end-to-end circuit connectivity on a call-by-call shared basis, where a "circuit" consists of Ethernet segments at the ends that are mapped into Ethernet-over-SONET long-distance circuits. This paper focuses on the file-transfer application for such circuits. For this application, the CHEETAH service is proposed as an add-on to the primary Internet access service already in place for enterprise hosts. This allows an end host that is sending a file to first attempt setting up an end-to-end Ethernet/EoS circuit, and if rejected, fall back to the TCP/IP path. If the circuit setup is successful, the end host will enjoy a much shorter file-transfer delay than on the TCP/IP path. To determine the conditions under which an end host with access to the CHEETAH service should attempt circuit setup, we analyze mean file-transfer delays as a function of call blocking probability in the circuit-switched network, probability of packet loss in the IP network, round-trip times, link rates, and so on.

  20. Femtosecond switching with semiconductor-optical-amplifier-based Symmetric Mach - Zehnder-type all-optical switch

    International Nuclear Information System (INIS)

    We investigate the effect of intraband carrier dynamics on a nonlinear phase shift induced in a semiconductor optical amplifier (SOA) in terms of its applicability to the Symmetric Mach - Zehnder (SMZ) all-optical switch. Nonlinear phase shifts in an SOA and a passive semiconductor waveguide are compared under control-pulse durations ranging from 3.2 to 0.4 ps. The results show that femtosecond switching with higher efficiency is still possible by using the SOA. We experimentally achieve femtosecond (670 fs), femtojoule (140 fJ) switching with the SOA-based SMZ all-optical switch. [copyright] 2001 American Institute of Physics

  1. Test Mismatch in Switched-Current Circuits Using Wavelet Analysis"

    Institute of Scientific and Technical Information of China (English)

    GUO Jierong; HE Yigang; LIU Meirong; TANG Shengxue; LI Hongmin

    2007-01-01

    Errors of mismatch and currents calibration caused by channel geometrical variety in switched-current are investigated in this paper. The relation and computing of mismatch and sensitivity are discussed also, and then a measure method of switched current mismatch using wavelet decomposition is proposed. A selected group of same transconductance is choosing as a cohort firstly, and the sensitivities of cohort in relation to the variation of transconductance are computed. Compared with the nominal deviation and tolerance borderline, the optimization and testing can be performed. As an example, a sixth order chebyshev low-pass filter is simulated and tested. The results have justified the reliability and feasibility of the method.

  2. Analysis of Sampled Noise in Switched Current Circuits

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Herald Holger; Bogason, Gudmundur

    1997-01-01

    The understanding of noise in analog sampled data systems is vital for the design of high resolution circuitry. In this paper a general description of sampled and held noise is presented. The noise calculations are verified by measurements on an analog delay line implemented using switched curren...

  3. Performance modeling of fault-tolerant circuit-switched communication networks

    OpenAIRE

    Safaei, F.; Khonsari, A.; Fathy, M.; Alzeidi, N.; Ould-Khaoua, M.

    2006-01-01

    Circuit switching (CS) has been suggested as an efficient switching method for supporting simultaneous communications (such as data, voice, and images) across parallel systems due to its ability to preserve both communication performance and fault-tolerant demands in such systems. In this paper we present an efficient scheme to capture the mean message latency in 2D torus with CS in the presence of faulty components. We have also conducted extensive simulation experiments, the results of whic...

  4. New scheme of optical switch technology of time division

    Institute of Scientific and Technical Information of China (English)

    GAO Ze-hua; QI Yong-xing; JI Yue-feng; QIAN Zong-jue

    2006-01-01

    The optical time division switch scheme using optical scanning was proposed in this paper.Quick switching can be realized by the optical element and optical system based on the proposed scheme.The modulation velocity of the proposed scheme can be of the order of nanosecond,which is quick enough for the next generation of optical communication.This scheme will be a key technology in the optical network.The principle of the scheme is studied.The structure of the scheme is proposed and the performance is analyzed.

  5. Quality of service in optical packet switched networks

    CERN Document Server

    Rahbar, Akbar G

    2015-01-01

    This book is a comprehensive study on OPS networks, its architectures, and developed techniques for improving its quality of switching and managing quality of service.  The book includes: Introduction to OPS networks, OOFDM networks, GMPLS-enabled optical networks, QoS in OPS networks Hybrid contention avoidance/resolution schemes in both long-haul and metro optical networks Hybrid optical switching schemes

  6. CO2 laser pulse switching by optically excited semiconductors

    International Nuclear Information System (INIS)

    The construction and the study of a semi-conductor optical switch used for generating short infrared pulses and to analyse the semiconductor characteristics, are presented. The switch response time depends on semiconductor and control laser characteristics. The results obtained using a Ge switch controlled by N2, NdYag and Dye lasers are presented. The response time was 50 ns limited by Ge recombination time. The reflectivity increased from 7% to 59% using N2 laser to control the switch. A simple model for semiconductor optical properties that explain very well the experimental results, is also presented. (author)

  7. All-optical nonlinear switching cell made of photonic crystal.

    Science.gov (United States)

    Wirth Lima, A; da Silva, Marcio G; Ferreira, A C; Sombra, A S B

    2009-07-01

    We analyze and propose a directional optical coupler embedded in photonic crystal, which is driven by an external command signal. Therefore, this switching cell can work in an all-optical switch. The switching method uses a low-power external command signal, inserted in the central coupling region, which acts as another waveguide. The switching process is based on the change from the bar state to the cross state due to the external command signal. In our simulations we used the plane wave expansion method, finite-difference time-domain method, and our own binary propagation method.

  8. Silicon Photonics Integrated Circuits for Flexible Optical Systems

    OpenAIRE

    Orlandi, Piero

    2014-01-01

    This dissertation deals with the design and the characterization of novel reconfigurable silicon-on-insulator (SOI) devices to filter and route optical signals on-chip. Design is carried out through circuit simulations based on basic circuit elements (Building Blocks, BBs) in order to prove the feasibility of an approach allowing to move the design of Photonic Integrated Circuits (PICs) toward the system level. CMOS compatibility and large integration scale make SOI one of the most promis...

  9. Nanoelectromechanical digital logic circuits using curved cantilever switches with amorphous-carbon-coated contacts

    Science.gov (United States)

    Ayala, Christopher L.; Grogg, Daniel; Bazigos, Antonios; Bleiker, Simon J.; Fernandez-Bolaños, Montserrat; Niklaus, Frank; Hagleitner, Christoph

    2015-11-01

    Nanoelectromechanical (NEM) switches have the potential to complement or replace traditional CMOS transistors in the area of ultra-low-power digital electronics. This paper reports the demonstration of prototype circuits including the first 3-stage ring oscillator built using cell-level digital logic elements based on curved NEM switches. The ring oscillator core occupies an area of 30 μm × 10 μm using 6 NEM switches. Each NEM switch device has a footprint of 5 μm × 3 μm, an air gap of 60 μm and is coated with amorphous carbon (a-C) for reliable operation. The ring oscillator operates at a frequency of 6.7 MHz, and confirms the simulated inverter propagation delay of 25 ns. The successful fabrication and measurement of this demonstrator are key milestones on the way towards an optimized, scaled technology with sub-nanosecond switching times, lower operating voltages and VLSI implementation.

  10. Dynamical behaviors of a system with switches between the Rössler oscillator and Chua circuits

    International Nuclear Information System (INIS)

    The behaviors of a system that alternates between the Rössler oscillator and Chua's circuit is investigated to explore the influence of the switches on the dynamical evolution. Switches related to the state variables are introduced, upon which a typical switching dynamical model is established. Bifurcation sets of the subsystems are derived via analysis of the related equilibrium points, which divide the parameters into several regions corresponding to different types of attractors. The dynamics behave typically in period orbits with the variation of the parameters. The focus/cycle periodic switching phenomenon is explored in detail to present the mechanism of the movement. The period-doubling bifurcation to chaos can be observed via the doubling increase of the turning points related to the switches. Furthermore, period-decreasing sequences have been obtained, which can be explained by the variation of the eigenvalues associated with the equilibrium points of the subsystems

  11. Research on wet etching at MEMS torsion mirror optical switch

    Science.gov (United States)

    Zhang, Yi; Wang, Jifeng; Luo, Yuan

    2002-10-01

    Etching is a very important technique at MEMS micromachining. There are two kinds of etching processing, the one is wet etching and the other is dry etching. In this paper, wet selective etching with KOH and tetramethyl ammonium hydroxide (TMAH) etchants is researched in order to make a torsion mirror optical switch. The experiments results show that TMAH with superphosphate is more suitable at MEMS torsion mirror optical switch micromachining than KOH, and it also has good compatibility with IC processing. Also our experiments results show some different with other reported research data. More work will be done to improve the yield rate of MEMS optical switch.

  12. MPLS over Segmented WDM Optical Packet Switching Networks

    Directory of Open Access Journals (Sweden)

    Hakim Mellah

    2006-01-01

    Full Text Available Wavelength Division Multiplexing (WDM is a promising solution for data transport in future all-optical wide area networks. Such networks consist of fibers joined by dynamically controllable cross-connects which provide purely optical transport between pairs of network access stations. Optical packet switching (OPS is optical switching with the finest granularity. Incoming packets are switched all-optically without being converted to electrical signal. There are two categories of OPS networks. Slotted (synchronous OPS networks, in which all the packets have the same size and unslotted (asynchronous OPS networks, where packets may or may not have the same size. In this study we propose to integrate MPLS over slotted OPS networks by aggregating optical packets into a labeled optical burst. The burst has a fixed number of packets (segments. The number of segments in each burst is encoded in the experimental field of the MPLS header.

  13. AN EFFECTIVE MODEL TO EVALUATE BLOCKING PROBABILITY OF TIME-SLOTTED OPTICAL BURST SWITCHED NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Yang Zongkai; Ou Liang; Tan Xiansi

    2006-01-01

    Time-slotted optical burst switched network is a potential technique to support IP over Wavelength Division Multiplexing (WDM) by introduce Time Division Multiplexing (TDM) channel to Optical Burst Switching (OBS) technology. This paper presents a framework to evaluate blocking performance of time-slotted OBS networks with multi-fiber wavelength channels. The proposed model is efficient for not only single class traffic such as individual circuit switch traffics or best-effort traffics but also mixed multi-class traffics.The effectiveness of the proposed model is validated by simulation results. The study shows that blocking performance of multi-fiber TS-OBS network is acceptable for future Internet services.

  14. Power Efficiency of Steam Turbine Generator Switching into Thermal Circuit of Small and Medium Boiler Houses

    Directory of Open Access Journals (Sweden)

    R. I. Yesman

    2007-01-01

    Full Text Available The paper is devoted to the solution of the problem concerning power saving on the basis of small power-and-heat-supply plants.Power efficiency of power turbine generator switching into thermal circuit of small and medium boiler houses is justified in the paper.

  15. Power Efficiency of Steam Turbine Generator Switching into Thermal Circuit of Small and Medium Boiler Houses

    OpenAIRE

    R. I. Yesman; I. P. Yarmolchik; I. V. Rymashevski; Moroz, G. V.

    2014-01-01

    The paper is devoted to the solution of the problem concerning power saving on the basis of small power-and-heat-supply plants.Power efficiency of power turbine generator switching into thermal circuit of small and medium boiler houses is justified in the paper.

  16. Reduction of crosstalk on printed circuit board using genetic algorithm in switching power supply

    OpenAIRE

    Pong, MH; Wu, X; Lee, CM; Qian, Z.

    2001-01-01

    Crosstalk between printed circuit board (PCB) traces in switching power supplies may cause high electromagnetic interference emission. PCB layout plays an important part and a genetic algorithm (GA) is used to produce a layout with reduced crosstalk. A coupling index and a new way of representing a trace for the GA process is presented.

  17. Bi-directional high-side current sense circuit for switch mode power supplies

    DEFF Research Database (Denmark)

    Ekhtiari, Marzieh; Bruun, Erik; Andersen, Michael A. E.;

    2014-01-01

    and secondary sides of the transformer which is internally implemented inside the transformer. Therefore, curren t must be measured from the high voltage line in the presence of hig h input switching voltage. This paper proposes a resistive current s ensing circuit based on discrete components useful for input...

  18. Software Defined Networking (SDN) controlled all optical switching networks with multi-dimensional switching architecture

    Science.gov (United States)

    Zhao, Yongli; Ji, Yuefeng; Zhang, Jie; Li, Hui; Xiong, Qianjin; Qiu, Shaofeng

    2014-08-01

    Ultrahigh throughout capacity requirement is challenging the current optical switching nodes with the fast development of data center networks. Pbit/s level all optical switching networks need to be deployed soon, which will cause the high complexity of node architecture. How to control the future network and node equipment together will become a new problem. An enhanced Software Defined Networking (eSDN) control architecture is proposed in the paper, which consists of Provider NOX (P-NOX) and Node NOX (N-NOX). With the cooperation of P-NOX and N-NOX, the flexible control of the entire network can be achieved. All optical switching network testbed has been experimentally demonstrated with efficient control of enhanced Software Defined Networking (eSDN). Pbit/s level all optical switching nodes in the testbed are implemented based on multi-dimensional switching architecture, i.e. multi-level and multi-planar. Due to the space and cost limitation, each optical switching node is only equipped with four input line boxes and four output line boxes respectively. Experimental results are given to verify the performance of our proposed control and switching architecture.

  19. Analysis of AC Switch Machine in Switch Control Circuit%交流转辙机道岔控制电路重点解析

    Institute of Scientific and Technical Information of China (English)

    王渝

    2012-01-01

    This paper systematically sorts out and summarizes the key circuits in the switch control circuits of AC switch machine,including the starting circuit,the cutting off circuit,and the failure button relay circuit.And the author analyzes the key points of related designs,which are instructive to the design of AC switch control circuit in the future.%对交流转辙机道岔控制电路中启动电路、切断电路及故障按钮继电器电路等重点电路进行系统梳理和总结,并对相关的设计要点进行分析,对今后交流转辙机道岔控制电路的设计具有一定的指导意义。

  20. The analysis of linear parametric circuits with switched capacitors by compact modified method of curve fitting

    Directory of Open Access Journals (Sweden)

    M. E. Artemenko

    2011-10-01

    Full Text Available The analytical connections  between the topological resistive element’s connection matrix of ARC-prototype and the topological switched capacitor’s connection matrices of resistor’s switch-capacitor  equivalents   for both phases of SC-circuits were established  that permits to  analyze a switched-capacitor networks on the base of  element’s connection matrix of ARC-prototype. The formal mathematical apparatus of forming the SC-circuits’ difference equations based on element’s connection matrix of ARC-prototype was developed which allows to reduce the dimension of the analyzed model of SC-circuits to the number of prototype’s capacitors.

  1. Push-pull converter with energy saving circuit for protecting switching transistors from peak power stress

    Science.gov (United States)

    Mclyman, W. T. (Inventor)

    1981-01-01

    In a push-pull converter, switching transistors are protected from peak power stresses by a separate snubber circuit in parallel with each comprising a capacitor and an inductor in series, and a diode in parallel with the inductor. The diode is connected to conduct current of the same polarity as the base-emitter juction of the transistor so that energy stored in the capacitor while the transistor is switched off, to protect it against peak power stress, discharges through the inductor when the transistor is turned on, and after the capacitor is discharges through the diode. To return this energy to the power supply, or to utilize this energy in some external circuit, the inductor may be replaced by a transformer having its secondary winding connected to the power supply or to the external circuit.

  2. Design and fabrication of sub-μs silicon-on-insulator thermo-optic 4×4 switch matrix

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4×4 switch matrix with spot size converters (SSCs) and a new driving circuit are designed and fabricated. The introduction of a spot size converter (SSC) has decreased the insertion loss to less than 10dB and the new driving circuit has improved the response speed to less than 1μs.

  3. An optical fan for light beams for high-precision optical measurements and optical switching

    CERN Document Server

    Zhou, Zhi-Yuan; Ding, Dong-Sheng; Jiang, Yun-Kun; Zhang, Wei; Shi, Shuai; Shi, Bao-Sen; Guo, Guang-Can

    2014-01-01

    The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high precision optical measurements and high capacity and high speed optical communications. Here we show, a totally new method, based on a combination of these two properties and using the thermal dispersion and electro-optical effect of birefringent crystals, the construction of a simple and robust scheme to rotate a light beam like a fan. Using a computer-based digital image processing technique, we determine the temperature and the thermal dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science and optical communication networks.

  4. Protein-based integrated optical switching and modulation

    Science.gov (United States)

    Ormos, Pál; Fábián, László; Oroszi, László; Wolff, Elmar K.; Ramsden, Jeremy J.; Dér, András

    2002-05-01

    The static and dynamic response of optical waveguides coated with a thin protein film of bacteriorhodopsin was investigated. The size and kinetics of the light-induced refractive index changes of the adlayer were determined under different conditions of illumination. The results demonstrate the applicability of this protein as an active, programmable nonlinear optical material in all-optical integrated circuits.

  5. Multifunctional disk device for optical switch and temperature sensor

    Institute of Scientific and Technical Information of China (English)

    卞振宇; 梁瑞生; 张郁靖; 易丽璇; 赖根; 赵瑞通

    2015-01-01

    A multifunctional surface plasmon polariton disk device coupled by two metal–insulator–metal (MIM) waveguides is proposed and investigated numerically with finite-difference time-domain simulation. It can be used as optical switch and temperature sensor by filling disk with liquid crystal and ethanol, respectively. The simulation results demonstrate that the transmission characteristics of an optical switch can be manipulated by adjusting the radius of disk and the slit width between disk and MIM waveguides. The transmittance and modulation depth of optical switch at 1550 nm are up to 64.82%and 17.70 dB, respectively. As a temperature sensor, its figure of merit can reach 30.46. In this paper, an optical switch with better efficiency and a temperature sensor with better sensitivity can be achieved.

  6. Performance improvement for optical packet switch with shared buffers

    Institute of Scientific and Technical Information of China (English)

    Junjie Yang; Qingji Zeng; Jie Li; Tong Ye; Guolong Zhu

    2005-01-01

    @@ In this paper, an inner wavelength method is proposed to enlarge buffering capacity of shared fiber delay line buffers. In addition, an optical packet switch called extended shared buffer type optical packet switch(extended SB-OPS) is proposed to realize the inner wavelength method. In order to further improve performance of extended SB-OPS, a greedy algorithm based on inner wavelength method is introduced.The performance of extended SB-OPS is evaluated by simulation experiments.

  7. Potential roles of optical interconnections within broadband switching modules

    Science.gov (United States)

    Lalk, Gail R.; Habiby, Sarry F.; Hartman, Davis H.; Krchnavek, Robert R.; Wilson, Donald K.; Young, Kenneth C., Jr.

    1991-04-01

    An investigation of potential physical design bottlenecks in future broadband telecommunication switches has led to the identification of several areas where optical interconnections may play a role in the practical realization of required system performance. In the model used the speed and interconnection densities as well as requirements for ease-of-access and efficient power utilization challenge conventional partitioning and packaging strategies. Potential areas where optical interconnections may relieve some of the physical design bottlenecks include fiber management at the customer interface to the switch routing and distribution of high-density interconnections within the fabric of the switch and backplane interconnections to increase system throughput.

  8. Gate Driver Circuit of Power Electronic Switches with Reduced Number of Isolated DC/DC Converter for a Switched Reluctance Motor

    International Nuclear Information System (INIS)

    This paper presents a gate driver circuit for the switching devices used in the asymmetrical converter for a switched reluctance machine with reduced number of isolated dc/dc converters. Isolation required in the gate driver circuit of switching devices is indispensable. For the purpose of isolation different arrangements may be used such as pulse transformers. The dc/dc converter for isolation and powering the gate drive circuits is suitable, cheaper in cost and simple to implement. It is also significant that required number of isolation converters is much less than the switches used in converter. In addition, a simple logic circuit has been presented for producing the gate signals at correct phase sequence which is compared with the gated signals directly obtained from the encoder of an existing machine. (author)

  9. Computer simulations of stimulus dependent state switching in basic circuits of bursting neurons

    Science.gov (United States)

    Rabinovich, Mikhail; Huerta, Ramón; Bazhenov, Maxim; Kozlov, Alexander K.; Abarbanel, Henry D. I.

    1998-11-01

    We investigate the ability of oscillating neural circuits to switch between different states of oscillation in two basic neural circuits. We model two quite distinct small neural circuits. The first circuit is based on invertebrate central pattern generator (CPG) studies [A. I. Selverston and M. Moulins, The Crustacean Stomatogastric System (Springer-Verlag, Berlin, 1987)] and is composed of two neurons coupled via both gap junction and inhibitory synapses. The second consists of coupled pairs of interconnected thalamocortical relay and thalamic reticular neurons with both inhibitory and excitatory synaptic coupling. The latter is an elementary unit of the thalamic networks passing sensory information to the cerebral cortex [M. Steriade, D. A. McCormick, and T. J. Sejnowski, Science 262, 679 (1993)]. Both circuits have contradictory coupling between symmetric parts. The thalamocortical model has excitatory and inhibitory connections and the CPG has reciprocal inhibitory and electrical coupling. We describe the dynamics of the individual neurons in these circuits by conductance based ordinary differential equations of Hodgkin-Huxley type [J. Physiol. (London) 117, 500 (1952)]. Both model circuits exhibit bistability and hysteresis in a wide region of coupling strengths. The two main modes of behavior are in-phase and out-of-phase oscillations of the symmetric parts of the network. We investigate the response of these circuits, while they are operating in bistable regimes, to externally imposed excitatory spike trains with varying interspike timing and small amplitude pulses. These are meant to represent spike trains received by the basic circuits from sensory neurons. Circuits operating in a bistable region are sensitive to the frequency of these excitatory inputs. Frequency variations lead to changes from in-phase to out-of-phase coordination or vice versa. The signaling information contained in a spike train driving the network can place the circuit into one or

  10. A pixel circuit with reduced switching leakage for an organic light-emitting diode

    International Nuclear Information System (INIS)

    This paper presents a pixel circuit with reduced switching leakage for OLED microdisplays. A self-referenced feedback loop is designed to track the node voltages for leakage reduction during the holding period. A longer holding time using a smaller storage capacitor can be achieved using the leakage reduction technique. An experimental system based on a 60 × 80 pixel matrix is fabricated in a 0.35-μm CMOS process. The area of the pixel circuit is only 15 × 15 μm2. According to the measured results, the pixel circuit achieves a holding time of longer than 500 ms and the system exhibits a satisfied accuracy and linearity within a pixel current range from 100 pA to 3 nA. (semiconductor integrated circuits)

  11. Titanium Oxide Intelligent "Optical Switch" Surface

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Bio-mimic\tsuper-hydrophobic\tand super-hydrophilic switches were highly concerned because of their extensive application perspectives in gene transfers,non-loss liquid transportation,micro fluid,gene chips,and slow released drug.

  12. Circuit QED flip-flop memory with all-microwave switching

    OpenAIRE

    Andersen, Christian Kraglund; Mølmer, Klaus

    2014-01-01

    We present a theoretical proposal for a microwave driven circuit composed of superconducting resonators and qubits which shows a bistable behaviour, and we present a simple mechanism that allows single- or few-photon microwave pulses to work as Set- and Reset-signals that switch the circuit between its stable modes. The resulting system constitutes an ultra-low-energy Set-Reset flip-flop, and we show that its memory lifetime far exceeds the lifetime of states stored in any of its separate com...

  13. A novel high voltage start up circuit for an integrated switched mode power supply

    Energy Technology Data Exchange (ETDEWEB)

    Hu Hao; Chen Xingbi, E-mail: huhao21@uestc.edu.c [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2010-09-15

    A novel high voltage start up circuit for providing an initial bias voltage to an integrated switched mode power supply (SMPS) is presented. An enhanced mode VDMOS transistor, the gate of which is biased by a floating p-island, is used to provide start up current and sustain high voltage. An NMOS transistor having a high source to ground breakdown voltage is included to extend the bias voltage range to the SMPS. Simulation results indicate that the high voltage start up circuit can start and restart as designed. The proposed structure is believed to be more energy saving and cost-effective compared with other solutions. (semiconductor devices)

  14. Optical computation based on nonlinear total reflectional optical switch at the interface

    Indian Academy of Sciences (India)

    Jianqi Zhang; Huan Xu

    2009-03-01

    A new scheme of binary half adder and full adder is proposed. It realizes a kind of all-optical computation which is based on the polarization coding technique and the nonlinear total reflectional optical switches.

  15. Acousto-Optics Tunable Filter Based on a Hollow Optical Fiber for Broadband Polarization Switch Application

    Institute of Scientific and Technical Information of China (English)

    Jaewon; Lee; Jaewang; Yu; Sangsoo; Choi; Kyunghwan; Oh; Dong; Il; Yum; Byoung; Yoon; Kim

    2003-01-01

    A novel acousto-optic tunable filter (AOTF) using a hollow optical fiber (HOF) is proposed. Its broadband rejection over 100nm was observed and high polarization dependence as a polarization switch is discussed.

  16. All-semiconductor metamaterial-based optical circuit board at the microscale

    Energy Technology Data Exchange (ETDEWEB)

    Min, Li; Huang, Lirong, E-mail: lrhuang@hust.edu.cn [Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2015-07-07

    The newly introduced metamaterial-based optical circuit, an analogue of electronic circuit, is becoming a forefront topic in the fields of electronics, optics, plasmonics, and metamaterials. However, metals, as the commonly used plasmonic elements in an optical circuit, suffer from large losses at the visible and infrared wavelengths. We propose here a low-loss, all-semiconductor metamaterial-based optical circuit board at the microscale by using interleaved intrinsic GaAs and doped GaAs, and present the detailed design process for various lumped optical circuit elements, including lumped optical inductors, optical capacitors, optical conductors, and optical insulators. By properly combining these optical circuit elements and arranging anisotropic optical connectors, we obtain a subwavelength optical filter, which can always hold band-stop filtering function for various polarization states of the incident electromagnetic wave. All-semiconductor optical circuits may provide a new opportunity in developing low-power and ultrafast components and devices for optical information processing.

  17. All-semiconductor metamaterial-based optical circuit board at the microscale

    International Nuclear Information System (INIS)

    The newly introduced metamaterial-based optical circuit, an analogue of electronic circuit, is becoming a forefront topic in the fields of electronics, optics, plasmonics, and metamaterials. However, metals, as the commonly used plasmonic elements in an optical circuit, suffer from large losses at the visible and infrared wavelengths. We propose here a low-loss, all-semiconductor metamaterial-based optical circuit board at the microscale by using interleaved intrinsic GaAs and doped GaAs, and present the detailed design process for various lumped optical circuit elements, including lumped optical inductors, optical capacitors, optical conductors, and optical insulators. By properly combining these optical circuit elements and arranging anisotropic optical connectors, we obtain a subwavelength optical filter, which can always hold band-stop filtering function for various polarization states of the incident electromagnetic wave. All-semiconductor optical circuits may provide a new opportunity in developing low-power and ultrafast components and devices for optical information processing

  18. Design and performance of the beamlet optical switch

    Energy Technology Data Exchange (ETDEWEB)

    Rhodes, M.A.; Woods, B.W.; DeYoreo, J.J. [and others

    1996-06-01

    High-energy lasers for Inertial Confinement Fusion (ICF) experiments are typically designed with large apertures (>30 cm) to keep the fluence below the damage threshold of the various optical components. Until recently, no optical switch technology could be scaled to the aperture size, aperture shape (square), and switching speed required for the next generation of ICF drivers. This step is critical: The Beamlet multipass amplifier cavity uses a full-aperture optical switch to trap the laser pulse within the cavity and to divert the pulse out of the cavity when it reaches the required energy. By rotating the polarization of the beam, a Pockels cell in the switch controls whether the beam is transmitted through, or reflected from, the polarizer. In this article the authors describe an optical switch technology that does scale to the required aperture size and shape for Beamlet and the porposed National Ignition Facility (NIF) laser, and can employ a thin crystal. This switch consists of a thin-film polarizer and a plasma-electrode Pockels cell (PEPC), the latter originally invented at Lawrence Livermore National Laboratory (LLNL) in the 1980s and under further development since 1991. After discussing the PEPC concept, they present the design and optical performance of a 32 x 32 cm{sup 2} prototype PEPC, including discussions of the crystals, the PEPC assembly, the vacuum and gas system, and the high-voltage pulsers. Then they describe the performance of the 37 x 37 cm{sup 2} PEPC construced specifically for the Beamlet laser. Finally, they discuss important technology issues that arose during PEPC development: cathode sputtering, cathode heating, nonuniformities in the switching profile, switch-pulse leakage current, and an estimate of the plasma density and temperature produced during PEPC operation.

  19. Analysis and design of switched transmission line circuits for high-power wide-band radiation

    International Nuclear Information System (INIS)

    High-power wide-band (HPWB) radiators have been studied for a number of applications such as electromagnetic car stoppers. Switched transmission line circuits (STLCs) are widely used as ultra-wide-band (UWB) and wide-band (WB) pulse generators in HPWB radiators. Since the performance of a STLC depends on the methods used to connect the switch to the transmission line, in the stage of conceptual design, we qualitatively determine a method for the connection so as to increase the amplitude of the radiated electric fields and the energy efficiency. We present a circuit analysis for the STLC built by using this method. The results of the analysis are useful for understanding and designing HPWB radiators using STLCs. A couple of HPWB radiators based on this approach are introduced as examples.

  20. Advanced photonic integrated technologies for optical routing and switching

    Science.gov (United States)

    Masanovic, Milan L.; Burmeister, Emily; Dummer, Matthew M.; Koch, Brian; Nicholes, Steven C.; Jevremovic, Biljana; Nguyen, Kim; Lal, Vikrant; Bowers, John E.; Coldren, Larry A.; Blumenthal, Daniel J.

    2009-02-01

    In this paper, we report on the latest advances in implementation of the photonic integrated circuits (PICs) required for optical routing. These components include high-speed, high-performance integrated tunable wavelength converters and packet forwarding chips, integrated optical buffers, and integrated mode-locked lasers.

  1. Flexible Optical-Comb-Based Multi-Wavelength Conversion for Optical Switching and Multicast

    OpenAIRE

    Vilar Mateo, Ruth; Ramos Pascual, Francisco; Marques, C.; Nogueira, Regina Isabel; Teixeira, A; Llorente Sáez, Roberto; RAMOS, FRAN JOSE

    2011-01-01

    Experimental results on multi-wavelength conversion based on optical comb generation for optical switching and multicast applications are presented. All the newly generated channels showed good performance with clear and open eye diagrams. FP7-ICT- 2009-4-249142 FP7-ICT-2007-1- 216863 Vilar Mateo, R.; Ramos Pascual, F.; Marques, C.; Nogueira, RI.; Teixeira, A.; Llorente Sáez, R.; Ramos, FJ. (2011). Flexible Optical-Comb-Based Multi-Wavelength Conversion for Optical Switch...

  2. Polymorphic beams and Nature inspired circuits for optical current

    Science.gov (United States)

    Rodrigo, José A.; Alieva, Tatiana

    2016-10-01

    Laser radiation pressure is a basis of numerous applications in science and technology such as atom cooling, particle manipulation, material processing, etc. This light force for the case of scalar beams is proportional to the intensity-weighted wavevector known as optical current. The ability to design the optical current according to the considered application brings new promising perspectives to exploit the radiation pressure. However, this is a challenging problem because it often requires confinement of the optical current within tight light curves (circuits) and adapting its local value for a particular task. Here, we present a formalism to handle this problem including its experimental demonstration. It consists of a Nature-inspired circuit shaping with independent control of the optical current provided by a new kind of beam referred to as polymorphic beam. This finding is highly relevant to diverse optical technologies and can be easily extended to electron and x-ray coherent beams.

  3. Magneto-optical switch with amorphous silicon waveguides on magneto-optical garnet

    Science.gov (United States)

    Ishida, Eiichi; Miura, Kengo; Shoji, Yuya; Mizumoto, Tetsuya; Nishiyama, Nobuhiko; Arai, Shigehisa

    2016-08-01

    We fabricated a magneto-optical (MO) switch with a hydrogenated amorphous silicon waveguide on an MO garnet. The switch is composed of a 2 × 2 Mach-Zehnder interferometer (MZI). The switch state is controlled by an MO phase shift through a magnetic field generated by a current flowing in an electrode located on the MZI. The switching operation was successfully demonstrated with an extinction ratio of 11.7 dB at a wavelength of 1550 nm.

  4. All-Optical Switches in Optical Time-Division Multiplexing Technology: Theory,Experience and Application

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Optical time division multiplexing (OTDM) is one of thepromisinig ways for the future high-speed optical fiber communication networks. All-optical switch is, being one of the core technologies of OTDM systems and networks, crucial to realize the various signal processes including time-division demultiplexing, packet switching, all-optical regenerating and so on. This thesis mainly studies various all-optical switch technologies and their utilization in the fields of all-optical signal processings in the OTDM systems and networks. The main jobs are listed as follows.(1) A novel all-optical ultrafast demultiplexing scheme using the soliton self-trapping effect in birefringent fiber is proposed.(2) The demultiplexing performance of the Nonlinear Optical Loop Mirror(NOLM) is thoroughly analyzed and its optimization is further discussed.(3) The performance analysis and the configuration optimization of the all-optical switches based on the Semiconductor Optical Amplifier(SOA) are systematically presented. The speed limitation of the all-optical SOA switches induced by the fast gain depletion of SOA is discussed. Besides, a novel SOA switch is proposed, which adopts the asymmetric Mach-Zehnder Interferometer configuration.(4) The 8×2\\^5 Gb/s OTDM experimental transmission system along 105 km standard fiber is realized using the NOLM demultiplexer.(5) The NOLM switch is used to realize the all-optical 3R regeneration of 2\\^5 Gb/s Return-to-Zero signal.(6) The feasibility and limitation of the all-optical SOA packet switch is discussed. And a developed MZI configuration of SOA packet switch is further shown to improve the packet switching performance. Finally, an all-optical packet dropping node suitable in the networks with ring or bus configuration and an all-optical packet switching node in the ShuffleNet networks are proposed to show the feasibility of all-optical packet switching through combining the all-optical switches and the reasonable logic decisions.

  5. Design of switched-capacitor filter circuits using low gain amplifiers

    CERN Document Server

    Serra, Hugo Alexandre de Andrade

    2015-01-01

    This book describes the design of switched-capacitor filter circuits using low gain amplifiers and demonstrates some techniques that can minimize the effects of parasitic capacitances during the design phase. Focus is given in the design of low-pass and band-pass SC filters, and how higher order filters can be achieved using cascaded biquadratic filter sections. The authors also describe a low voltage implementation of a low-pass SC filter.

  6. Actively Q-switched erbium-doped fiber ring laser with a nanosecond ceramic optical switch

    International Nuclear Information System (INIS)

    An actively Q-switched erbium-doped fiber laser with a fiber-pigtailed nanosecond ceramic optical switch is experimentally investigated in this paper. Firstly, the ceramic optical switch was systematically characterized. Then, it was used to actively Q-switch an all-fiber erbium-doped fiber ring laser. Stable Q-switching laser pulses with a repetition rate from 2 kHz–40 kHz were achieved. The minimum pulse width was measured to be ∼25 ns at 2 kHz when pumped at 150 mW, and the corresponding maximum peak power was ∼2.9 W. Multi-peak pulses were observed at low repetition rates and the reasons for these were analyzed. This study shows that a nanosecond ceramic switch can be used as a good Q switch due to its low insertion loss, high on/off ratio, ultrafast response, and low electrical power consumption. (paper)

  7. Optical Switching for Dynamic Distribution of Wireless-Over-Fiber Signals in Active Optical Networks

    DEFF Research Database (Denmark)

    Vegas Olmos, Juan José; Rodes, Guillermo; Tafur Monroy, Idelfonso

    2012-01-01

    of a four wavelength-division-multiplexed channel system operating on a WiMax frequency band and employing an orthogonal-frequency-division-multiplexing modulation at 625 Mbits/s per channel, transmission of the data over 20 km of optical fiber, and active switching in a 1 × 16 active optical switch...

  8. Switching circuits based on comparison operations and multiple-β transistor

    Institute of Scientific and Technical Information of China (English)

    吴训威; 杭国强

    1997-01-01

    By using comparison operations, three basic operations, AND, OR and NOT, in Boolean algebra are re-defined Based on the characteristic that the voltage signals are easy to implement comparison operation, various logic functions realized by connecting emitters of the bipolar transistor are analyzed. Furthermore, a novel multiple-β transistor and the linear AND-OR gate, which is composed of the transistor, are investigated. Super high-speed characteristic and multiple-cascade capability of the linear AND-OR gate are verified by PSPICE simulation. Based on the analysis of high-speed switch, which is compatible with the linear AND-OR gate, a high-speed inverter is proposed, which is composed of multiple-β transistors. The corresponding flip-flop design is also given. Finally, the criterion for using linear AND-OR gate to design high-speed switching circuits are presented. Some combinational and sequential circuits are designed as the practical examples. Discussion indicates that the switching circuits bas

  9. All-Optical Switching Based on Azo Polymer Material

    Institute of Scientific and Technical Information of China (English)

    DENG Yan; LUO Yan-Hua; WANG Pei; LU Yong-Hua; MING Hai; ZhANG Qi-Jing

    2007-01-01

    Conventional all-optical switches based on azo polymer films and the all-optical switches based on the attenuated total reflection (ATR) geometry are investigated. A conventional switch system, including a pump beam of 532nm and a probe beam of 650nm, is based on the photoinduced birefringence effect of azo polymer. An ATR switch in a prism-multilayer configuration is achieved by changing the reflectance of the probe beam with an external pump beam. The ATR method provides the substantial improvement of the speed and the efficiency of the modulation over the conventional method. Although the azo polymer response still remains relatively slow,an enhanced nonlinear refractive index of the azo polymer film can effectively increase the modulation.

  10. Power gating of VLSI circuits using MEMS switches in low power applications

    KAUST Repository

    Shobak, Hosam

    2011-12-01

    Power dissipation poses a great challenge for VLSI designers. With the intense down-scaling of technology, the total power consumption of the chip is made up primarily of leakage power dissipation. This paper proposes combining a custom-designed MEMS switch to power gate VLSI circuits, such that leakage power is efficiently reduced while accounting for performance and reliability. The designed MEMS switch is characterized by an 0.1876 ? ON resistance and requires 4.5 V to switch. As a result of implementing this novel power gating technique, a standby leakage power reduction of 99% and energy savings of 33.3% are achieved. Finally the possible effects of surge currents and ground bounce noise are studied. These findings allow longer operation times for battery-operated systems characterized by long standby periods. © 2011 IEEE.

  11. All-optical switching in metamaterial with high structural symmetry

    OpenAIRE

    Tuz, Vladimir R.; Prosvirnin, Sergey L.

    2011-01-01

    We argue the possibility of realization of a polarization insensitive all-optical switching in a planar metamaterial composed of a 4-fold periodic array of two concentric metal rings placed on a substrate of nonlinear material. It is demonstrated that a switching may be achieved between essentially different values of transmission near the resonant frequency of the high-quality-factor Fano-shape trapped-mode excitation.

  12. Fabrication and demonstration of 1 × 8 silicon–silica multi-chip switch based on optical phased array

    Science.gov (United States)

    Katayose, Satomi; Hashizume, Yasuaki; Itoh, Mikitaka

    2016-08-01

    We experimentally demonstrated a 1 × 8 silicon–silica hybrid thermo-optic switch based on an optical phased array using a multi-chip integration technique. The switch consists of a silicon chip with optical phase shifters and two silica-based planar lightwave circuit (PLC) chips composed of optical couplers and fiber connections. We adopted a rib waveguide as the silicon waveguide to reduce the coupling loss and increase the alignment tolerance for coupling between silicon and silica waveguides. As a result, we achieved a fast switching response of 81 µs, a high extinction ratio of over 18 dB and a low insertion loss of 4.9–8.1 dB including a silicon–silica coupling loss of 0.5 ± 0.3 dB at a wavelength of 1.55 µm.

  13. Universal discrete Fourier optics RF photonic integrated circuit architecture.

    Science.gov (United States)

    Hall, Trevor J; Hasan, Mehedi

    2016-04-01

    This paper describes a coherent electro-optic circuit architecture that generates a frequency comb consisting of N spatially separated orders using a generalised Mach-Zenhder interferometer (MZI) with its N × 1 combiner replaced by an optical N × N Discrete Fourier Transform (DFT). Advantage may be taken of the tight optical path-length control, component and circuit symmetries and emerging trimming algorithms offered by photonic integration in any platform that offers linear electro-optic phase modulation such as LiNbO3, silicon, III-V or hybrid technology. The circuit architecture subsumes all MZI-based RF photonic circuit architectures in the prior art given an appropriate choice of output port(s) and dimension N although the principal application envisaged is phase correlated subcarrier generation for all optical orthogonal frequency division multiplexing. A transfer matrix approach is used to model the operation of the architecture. The predictions of the model are validated by simulations performed using an industry standard software tool. Implementation is found to be practical. PMID:27137048

  14. Universal discrete Fourier optics RF photonic integrated circuit architecture.

    Science.gov (United States)

    Hall, Trevor J; Hasan, Mehedi

    2016-04-01

    This paper describes a coherent electro-optic circuit architecture that generates a frequency comb consisting of N spatially separated orders using a generalised Mach-Zenhder interferometer (MZI) with its N × 1 combiner replaced by an optical N × N Discrete Fourier Transform (DFT). Advantage may be taken of the tight optical path-length control, component and circuit symmetries and emerging trimming algorithms offered by photonic integration in any platform that offers linear electro-optic phase modulation such as LiNbO3, silicon, III-V or hybrid technology. The circuit architecture subsumes all MZI-based RF photonic circuit architectures in the prior art given an appropriate choice of output port(s) and dimension N although the principal application envisaged is phase correlated subcarrier generation for all optical orthogonal frequency division multiplexing. A transfer matrix approach is used to model the operation of the architecture. The predictions of the model are validated by simulations performed using an industry standard software tool. Implementation is found to be practical.

  15. Optical networking by DLP-based switched blazed grating

    Science.gov (United States)

    Lin, Hoang Yan; Chung, Shuang-Chao

    2005-02-01

    All-optical modules are devices which process and transport optical signals without transforming to electronic signals. They get more attention as the optical communication network becomes more and more complicated. Among them, OADM (optical add drop module) is one of the most important devices in the optical DWDM (dense wavelength division multiplex) network. It plays the role of a node in network to upload/download signals or to route signals for optical performance monitoring. Applied broadly in projection display systems, DLP (Digital Light Processing) from Texas Instruments turns out to be a versatile device for optical signal processing. The working principle of DLP is based on so called switched-blazed-grating. Part of its micro-mirror array can be formed as a dynamic blazed grating with a period of 14 μm by tilting the micro-mirrors at an angle of +/-12 degrees. It is expected to function as either a switch or an attenuator by directing total or part of the incident light between the 2nd and -2nd diffraction orders. In this paper, we investigate the optical characteristics of a switched-blazed-grating, its application as a re-configurable OADM, and the performance of such a device. Ray tracing and optical analysis of the OADM are made by using package software ASAP from Breault Research Organization. In conclusion, as a mature and reliable MEMS device, DLP-based switched-blazed-grating provides a very versatile platform for digital optical signal processing and can be used as a dynamic optical-networking device with good performance.

  16. Experiments on two-resonator circuit quantum electrodynamics. A superconducting quantum switch

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Elisabeth Christiane Maria

    2013-05-29

    The field of cavity quantum electrodynamics (QED) studies the interaction between light and matter on a fundamental level. In typical experiments individual natural atoms are interacting with individual photons trapped in three-dimensional cavities. Within the last decade the prospering new field of circuit QED has been developed. Here, the natural atoms are replaced by artificial solid state quantum circuits offering large dipole moments which are coupled to quasi-onedimensional cavities providing a small mode volume and hence a large vacuum field strength. In our experiments Josephson junction based superconducting quantum bits are coupled to superconducting microwave resonators. In circuit QED the number of parameters that can be varied is increased and regimes that are not accessible using natural atoms can be entered and investigated. Apart from design flexibility and tunability of system parameters a particular advantage of circuit QED is the scalability to larger system size enabled by well developed micro- and nanofabrication tools. When scaling up the resonator-qubit systems beyond a few coupled circuits, the rapidly increasing number of interacting subsystems requires an active control and directed transmission of quantum signals. This can, for example, be achieved by implementing switchable coupling between two microwave resonators. To this end, a superconducting flux qubit is used to realize a suitable coupling between two microwave resonators, all working in the Gigahertz regime. The resulting device is called quantum switch. The flux qubit mediates a second order tunable and switchable coupling between the resonators. Depending on the qubit state, this coupling can compensate for the direct geometric coupling of the two resonators. As the qubit may also be in a quantum superposition state, the switch itself can be ''quantum'': it can be a superposition of ''on'' and ''off''. This work

  17. Thermo-optic switches using sol-gel processed hybrid materials

    Science.gov (United States)

    Kribich, Kada R.; Barry, Henry; Copperwhite, Robert; Kolodziejczyk, Boleslaw; O'Dwyer, Kieran; Sabattie, Jean-Marc; MacCraith, Brian D.

    2004-08-01

    There is a clear need for low cost, high performance and large-scale production of photonic chips. Network development requires more interconnecting components. A flexible and low-cost process using good quality material is necessary. The sol-gel process is a chemical method to fabricate glasses at ambient pressure and moderate temperature. The resulting material properties can be tuned depending on the precursors used. Hybrid materials, mixing organic and inorganic parts, offer the advantages of polymer-like materials and glasses. We have developed sol-gel-processed integrated optical circuits using hybrid materials. We report on the development of active devices based on the thermo-optic effect. Thermo-optic coefficients as high as -2.10-4/°K have been measured in our materials. This enables the design of compact devices with low power consumption. Our goal is to utilise the thermo-optic effect in the development of integrated optical switches. The kHz response time of such switches makes them unsuitable for modulation applications, but they can be used for network protection, reconfiguration purposes in routing and multiplexing applications such as Code Division Multiplexing. New designs, based on multimode interference couplers (MMIC), have also been created. In this work we first describe the synthesis of the hybrid materials as well as the fabrication processes. Using the measured properties of the materials developed, we can simulate the optical and thermal properties of the target devices. The simulation results have been exploited to model and optimise a range of switch designs, including MMI-based 1xN switches. Finally, we report on the full characterisation of the different structures and devices created in terms of fabrication quality and optical and thermal response.

  18. qZS-Based Soft-Switching DC/DC Converter with a Series Resonant LC Circuit

    OpenAIRE

    Vinnikov, D; Zaķis, J; Liivik, L; Raņķis, I

    2013-01-01

    This paper discusses further modifications of the recent popular qZS-based DC/DC converter design by the introduction of the resonant LC circuit in series to the primary winding of the isolation transformer. The primary aim is to achieve the zero voltage and zero current switching of transistors. As an additional benefit of the resonant LC circuit, the converter is able to perform the voltage buck function simply by changing the switching frequency of the transistors. The control principle of...

  19. Novel Technologies for Design and Analysis of Switching Mode Power-Supply Circuit Based on Solitary Electromagnetic Wave Theory

    OpenAIRE

    Tohya, Hirokazu; Toya, Noritaka

    2014-01-01

    The novel solitary electromagnetic wave (SEMW) theory and the novel design methodologies of the switching mode power supply circuit (SMPC) are presented. The SEMW theory was developed as a basic theory of the design of all kinds of the switching mode circuit including SMPC by fusing the physics of semiconductor, nonlinear undulation, and electromagnetic wave. When the SEMW theory is used, the electromagnetic analysis of SMPC becomes possible by using only the real parameters based on the phys...

  20. High-speed Integrated Circuits for electrical/Optical Interfaces

    DEFF Research Database (Denmark)

    Jespersen, Christoffer Felix

    2008-01-01

    This thesis is a continuation of the effort to increase the bandwidth of communicationnetworks. The thesis presents the results of the design of several high-speed electrical ircuits for an electrical/optical interface. These circuits have been a contribution to the ESTA project in collaboration...... circuits at the receiver interface, though VCOs are also found in the transmitter where a multitude of independent sources have to be mutually synchronized before multiplexing. The circuits are based on an InP DHBT process (VIP-2) supplied by Vitesse and made publicly available as MPW. The VIP-2 process...... represents the avant-garde of InP technology, with ft and fmax well above 300 GHz. Principles of high speed design are presented and described as a useful background before proceeding to circuits. A static divider is used as an example to illustrate many of the design principles. Theory and fundamentals...

  1. Plasmonic nanopatch array for optical integrated circuit applications

    OpenAIRE

    Shi-Wei Qu; Zai-Ping Nie

    2013-01-01

    Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will def...

  2. Polyguide polymeric technology for optical interconnect circuits and components

    Science.gov (United States)

    Booth, Bruce L.; Marchegiano, Joseph E.; Chang, Catherine T.; Furmanak, Robert J.; Graham, Douglas M.; Wagner, Richard G.

    1997-04-01

    The expanding information revolution has been made possible by the development of optical communication technology. To meet the escalating demand for information transmitted and processed at high data rates and the need to circumvent the growing electronic circuit bottlenecks, mass deployment of not only optical fiber networks but manufacturable optical interconnect circuits, components and connectors for interfacing fibers and electronics that meet economic and performance constraints are absolutely necessary. Polymeric waveguide optical interconnection are considered increasingly important to meet these market needs. DuPont's polyguide polymeric integrated optic channel waveguide system is thought by many to have considerable potential for a broad range of passive optical interconnect applications. In this paper the recent advances, status, and unique attributes of the technology are reviewed. Product and technology developments currently in progress including parallel optical ink organization and polymer optical interconnect technology developments funded by DARPA are used as examples to describe polyguide breadth and potential for manufacture and deployment of optical interconnection products for single and multimode telecom and datacom waveguide applications.

  3. Optical Packet Routing Performance of an Optical Packet Switch With an Optical Digital/Analog-Conversion-Type Header Processor (Wavelength Label Switch)

    Institute of Scientific and Technical Information of China (English)

    Hiroyuki; Uenohara; Takeshi; Seki; Kohroh; Kobayashi

    2003-01-01

    We demonstrate the routing operation of optical packets by an optical packet switch consisting of an optical digital-to-analog conversion-type header processor, a wavelength converter using an electrically-tunable laser, and an arrayed-waveguide grating router. A packet transfer by two-bit optical header was achieved for the first time.

  4. Optical Packet Routing Performance of an Optical Packet Switch Digital/ Analog-Conversion-Type With an Optical Header Processor (Wavelength Label Switch)

    Institute of Scientific and Technical Information of China (English)

    Hiroyuki Uenohara; Takeshi Seki; Kohroh Kobayashi

    2003-01-01

    We demonstrate the routing operation of optical packets by an optical packet switch consisting of an optical digital-to-analog conversion-type header processor, a wavelength converter using an electrically-tunable laser, and an arrayed-waveguide grating router. A packet transfer by two -bit optical header was achieved for the first time.

  5. Design principles and realization of electro-optical circuit boards

    Science.gov (United States)

    Betschon, Felix; Lamprecht, Tobias; Halter, Markus; Beyer, Stefan; Peterson, Harry

    2013-02-01

    The manufacturing of electro-optical circuit boards (EOCB) is based to a large extent on established technologies. First products with embedded polymer waveguides are currently produced in series. The range of applications within the sensor and data communication markets is growing with the increasing maturity level. EOCBs require design flows, processes and techniques similar to existing printed circuit board (PCB) manufacturing and appropriate for optical signal transmission. A key aspect is the precise and automated assembly of active and passive optical components to the optical waveguides which has to be supported by the technology. The design flow is described after a short introduction into the build-up of EOCBs and the motivation for the usage of this technology within the different application fields. Basis for the design of EOCBs are the required optical signal transmission properties. Thereafter, the devices for the electro-optical conversion are chosen and the optical coupling approach is defined. Then, the planar optical elements (waveguides, splitters, couplers) are designed and simulated. This phase already requires co-design of the optical and electrical domain using novel design flows. The actual integration of an optical system into a PCB is shown in the last part. The optical layer is thereby laminated to the purely electrical PCB using a conventional PCB-lamination process to form the EOCB. The precise alignment of the various electrical and optical layers is thereby essential. Electrical vias are then generated, penetrating also the optical layer, to connect the individual electrical layers. Finally, the board has to be tested electrically and optically.

  6. Field Experiments on 10 kV Switching Shunt Capacitor Banks Using Ordinary and Phase-Controlled Vacuum Circuit Breakers

    OpenAIRE

    Wenxia Sima; Mi Zou; Qing Yang; Ming Yang; Licheng Li

    2016-01-01

    During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs) are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor banks. An analytical analysis for switching 10 kV shunt capacitor banks is presented on the basis of ...

  7. An Automatic Switched-Capacitor Cell Balancing Circuit for Series-Connected Battery Strings

    Directory of Open Access Journals (Sweden)

    Yuanmao Ye

    2016-02-01

    Full Text Available In this paper, a novel voltage equalizer is developed for series battery strings based on the two-phase switched capacitor technique. Different from the conventional voltage equalizers which are developed by switched-mode power converters, bulky magnetic components and complex monitoring and control system are avoided in the proposed system. Just a pair of complementary pulse signals with constant switching frequency and fixed duty ratio are required to control all of switches employed in the proposed voltage equalizer, and charge transfers from the higher voltage battery cells to lower voltage ones automatically. The circuit configuration and operation principle are provided in this paper. The model of the proposed voltage equalizer is also derived. Comparison with other works indicates that the proposed method is superior to the conventional switched-capacitor (SC voltage equalizer for the high stack of series battery strings. Experimental results demonstrate that the proposed voltage equalization system is capable of excellent voltage balancing performance with a simple control method.

  8. Bistable optical electrical/microwave switching using optically coupled monolithically integrated GaAlAs translasers

    OpenAIRE

    Lau, K Y; Yariv, A.

    1984-01-01

    A novel switching device consisting of optically coupled laser and field-effect transistor monolithically integrated on a semi-insulating substrate is demonstrated. The physical origin of the bistable behavior is illustrated. The input and output to this device can take the form of optical and/or electrical signals. Applications of this device in optical, electrical, microwave switching, and pulse-position/pulse frequency demodulation are illustrated.

  9. A Component-Minimized Single-Phase Active Power Decoupling Circuit with Reduced Current Stress to Semiconductor Switches

    DEFF Research Database (Denmark)

    Tang, Yi; Blaabjerg, Frede

    2015-01-01

    This letter proposes a novel circuit topology which can realize the power decoupling function without adding additional active switches into the circuit. The dc-link capacitor of a full bridge rectifier is split into two identical parts and the midpoint is connected to one leg through a filter in...

  10. Enhancement of galloping-based wind energy harvesting by synchronized switching interface circuits

    Science.gov (United States)

    Zhao, Liya; Liang, Junrui; Tang, Lihua; Yang, Yaowen; Liu, Haili

    2015-04-01

    Galloping phenomenon has attracted extensive research attention for small-scale wind energy harvesting. In the reported literature, the dynamics and harvested power of a galloping-based energy harvesting system are usually evaluated with a resistive AC load; these characteristics might shift when a practical harvesting interface circuit is connected for extracting useful DC power. In the family of piezoelectric energy harvesting interface circuits, synchronized switching harvesting on inductor (SSHI) has demonstrated its advantage for enhancing the harvested power from existing base vibrations. This paper investigates the harvesting capability of a galloping-based wind energy harvester using SSHI interfaces, with a focus on comparing the performances of Series SSHI (S-SSHI) and Parallel SSHI (P-SSHI) with that of a standard DC interface, in terms of power at various wind speeds. The prototyped galloping-based piezoelectric energy harvester (GPEH) comprises a piezoelectric cantilever attached with a square-sectioned bluff body made of foam. Equivalent circuit model (ECM) of the GPEH is established and system-level circuit simulations with SSHI and standard interfaces are performed and validated with wind tunnel tests. The benefits of SSHI compared to standard circuit become more significant when the wind speed gets higher; while SSHI circuits lose the benefits at small wind speeds. In both experiment and simulation, the superiority of P-SSHI is confirmed while S-SSHI demands further investigation. The power output is increased by 43.75% with P-SSHI compared to the standard circuit at a wind speed of 6m/s.

  11. Vacuum interrupter, high reliability component of distribution switches, circuit breakers and contactors

    Institute of Scientific and Technical Information of China (English)

    SLADE Paul G.; LI Wang-pei; MAYO Stephen; SMITH R.Kirkland; TAYLOR Erik D.

    2007-01-01

    The use of vacuum interrupters (VIs) as the current interruption component for switches, circuit breakers, reclosers and contactors operating at distribution voltages has escalated since their introduction in the mid-1950's. This electrical product has developed a dominating position for switching and protecting distribution circuits. VIs are even being introduced into switching products operating at transmission voltages. Among the reasons for the VI's popularity are its compactness, its range of application, its low cost, its superb electrical and mechanical life and its ease of application. Its major advantage is its well-established reliability. In this paper we show how this reliability has been achieved by design, by mechanical life testing and by electrical performance testing. We introduce the "sealed for life" concept for the VI's integrity. We discuss this in terms of what is meant by a practical leak rate for VIs with a life of over 30 years. We show that a simple high voltage withstand test is an easy and effective method for monitoring the long-term vacuum integrity. Finally we evaluate the need for routine inspection of this electrical product when it is used in adverse ambient environments.

  12. High-contrast, all-optical switching in bacteriorhodopsin films

    Science.gov (United States)

    Banyal, Ravinder Kumar; Raghavendra Prasad, B.

    2005-09-01

    We report experiments with nonlinear-absorption-based, high-contrast, all-optical switching in photochromic bacteriorhodopsin (BR) films. The switching action is accomplished by control of the transmission of a weak probe beam through a BR sample with the help of strong pump beam illumination at 532 nm wavelength. We found that the switching properties of BR films depend on several experimentally controllable parameters such as probe wavelength, pump beam intensity, and excitation rate. A comparative study of the switching behavior and other parameters of practical use was carried out at three probe wavelengths (543, 594, and 633 nm) and various beam powers and pump excitation rates. The results are presented for commercially available wild-type and D96N variant BR films.

  13. Reconfigurable optical interleaver modules with tunable wavelength transfer matrix function using polymer photonics lightwave circuits.

    Science.gov (United States)

    Chen, Changming; Niu, Xiaoyan; Han, Chao; Shi, Zuosen; Wang, Xinbin; Sun, Xiaoqiang; Wang, Fei; Cui, Zhanchen; Zhang, Daming

    2014-08-25

    A transparent reconfigurable optical interleaver module composed of cascaded AWGs-based wavelength-channel-selector/interleaver monolithically integrated with multimode interference (MMI) variable optical attenuators (VOAs) and Mach-Zehnder interferometer (MZI) switch arrays was designed and fabricated using polymer photonic lightwave circuits. Highly fluorinated photopolymer and grafting modified organic-inorganic hybrid material were synthesized as the waveguide core and caldding, respectively. Thermo-optic (TO) tunable wavelength transfer matrix (WTM) function of the module can be achieved for optical routing network. The one-chip transmission loss is ~ 6 dB and crosstalk is less than ~25 dB for transverse-magnetic (TM) mode. The crosstalk and extinction ratio of the MMI VOAs were measured as -15.2 dB and 17.5 dB with driving current 8 mA, respectively. The modulation depth of the TO switches is obtained as ~18.2 dB with 2.2 V bias. Proposed novel interleaver module could be well suited for DWDM optical communication systems.

  14. Neuromorphic opto-electronic integrated circuits for optical signal processing

    Science.gov (United States)

    Romeira, B.; Javaloyes, J.; Balle, S.; Piro, O.; Avó, R.; Figueiredo, J. M. L.

    2014-08-01

    The ability to produce narrow optical pulses has been extensively investigated in laser systems with promising applications in photonics such as clock recovery, pulse reshaping, and recently in photonics artificial neural networks using spiking signal processing. Here, we investigate a neuromorphic opto-electronic integrated circuit (NOEIC) comprising a semiconductor laser driven by a resonant tunneling diode (RTD) photo-detector operating at telecommunication (1550 nm) wavelengths capable of excitable spiking signal generation in response to optical and electrical control signals. The RTD-NOEIC mimics biologically inspired neuronal phenomena and possesses high-speed response and potential for monolithic integration for optical signal processing applications.

  15. 100GHz Integrated All-Optical Switch Enabled by ALD

    CERN Document Server

    Moille, Gregory; Morgenroth, Laurence; Lehoucq, Gaëlle; Neuilly, François; Hu, Bowen; Decoster, Didier; de Rossi, Alfredo

    2015-01-01

    The carrier lifetime of a photonic crystal all-optical switch is optimized by controlling the surface of GaAs by Atomic Layer Deposition. We demonstrate an all optical modulation capability up to 100GHz at Telecom wavelengths, with a contrast as high as 7dB. Wavelength conversion has also been demonstrated at a repetition rate of 2.5GHz with average pump power of about 0.5mW

  16. Simulation of Optical Packet—Switched Metropolitan Area Network

    Institute of Scientific and Technical Information of China (English)

    朱炳春; 贾潞华; 等

    2002-01-01

    This paper introduces architectures of two types optical packet-switched metropolitan area networks and their media access control protocols.We have designed ralated network simulation systems.With these simulation systems,the characteristics and performanceof the two MANs can be achieved.

  17. Optical Switching and Bit Rates of 40 Gbit/s and above

    DEFF Research Database (Denmark)

    Ackaert, A.; Demester, P.; O'Mahony, M.;

    2003-01-01

    Optical switching in WDM networks introduces additional aspects to the choice of single channel bit rates compared to WDM transmission systems. The mutual impact of optical switching and bit rates of 40 Gbps and above is discussed....

  18. Optical switching by stimulated thermal Rayleigh scattering

    Science.gov (United States)

    Peterson, Lauren M.

    1986-06-01

    Preliminary experiments were conducted whose ultimate goal is to develop all-optical control functions useful in an all-optical or optical-electronic hybrid digital computer or for optical interconnects. Stimulated thermal Rayleigh scattering (STRS) based upon generator experiments was pursued for scattering angles of 90 deg and 180 deg (backscattering). A pulsed nitrogen laser pumped dye laser served as the radiation source and the interaction medium was a liquid to which an absorbing dye was added. STRS amplifier experiments were successful and gain was observed and studied parametrically using eosine dye in ethanol. The gain was found to increase (although the gain coefficient decreased) with increasing pump power and the gain was found to be a maximum at an absorption coefficient of about 2.6 per cm. The generator experiments did not lead to stimulated scattering due to the limited output power of the laser and its multi-longitudinal spectral mode content. These studies will be continued along with analytical modeling in order to characterize the interaction and to enable the optimization of the scattering process.

  19. Study of switching electric circuits with DC hybrid breaker, one stage

    Science.gov (United States)

    Niculescu, T.; Marcu, M.; Popescu, F. G.

    2016-06-01

    The paper presents a method of extinguishing the electric arc that occurs between the contacts of direct current breakers. The method consists of using an LC type extinguishing group to be optimally sized. From this point of view is presented a theoretical approach to the phenomena that occurs immediately after disconnecting the load and the specific diagrams are drawn. Using these, the elements extinguishing group we can choose. At the second part of the paper there is presented an analyses of the circuit switching process by decomposing the process in particular time sequences. For every time interval there was conceived a numerical simulation model in MATLAB-SIMULINK medium which integrates the characteristic differential equation and plots the capacitor voltage variation diagram and the circuit dumping current diagram.

  20. Control of internal and external short circuits in lithium batteries using a composite thermal switch

    Science.gov (United States)

    Mcdonald, Robert C.; Pickett, Jerome; Goebel, Franz

    1991-01-01

    A composite material has been developed, consisting of a blend of metal and fluorocarbon particles, which behaves as an electronic conductor at room temperature and which abruptly becomes an insulator at a predetermined temperature. This switching behavior results from the difference in thermal expansion coefficients between the conductive and non-conductive portions of the composite. This material was applied as a thin film between the carbon cathode in Li/SOCl2 cells, and the metallic cathode current collector. Using test articles incorporating this feature it was shown that lithium cells externally heated or internally heated during a short circuit lost rate capability and the ability to overheat well below the melting point of lithium (180 C). Thus, during an internal or external cell short circuit, the potential for thermal runaway involving reactions of molten lithium is avoided.

  1. Synchronising chaotic Chua's circuit using switching feedback control based on piecewise quadratic Lyapunov functions

    International Nuclear Information System (INIS)

    This paper investigates the chaos synchronisation between two coupled chaotic Chua's circuits. The sufficient condition presented by linear matrix inequalities (LMIs) of global asymptotic synchronisation is attained based on piecewise quadratic Lyapunov functions. First, we obtain the piecewise linear differential inclusions (pwLDIs) model of synchronisation error dynamics, then we design a switching (piecewise-linear) feedback control law to stabilise it based on the piecewise quadratic Laypunov functions. Then we give some numerical simulations to demonstrate the effectiveness of our theoretical results

  2. A Nanostructured Composites Thermal Switch Controls Internal and External Short Circuit in Lithium Ion Batteries

    Science.gov (United States)

    McDonald, Robert C.; VanBlarcom, Shelly L.; Kwasnik, Katherine E.

    2013-01-01

    A document discusses a thin layer of composite material, made from nano scale particles of nickel and Teflon, placed within a battery cell as a layer within the anode and/or the cathode. There it conducts electrons at room temperature, then switches to an insulator at an elevated temperature to prevent thermal runaway caused by internal short circuits. The material layer controls excess currents from metal-to-metal or metal-to-carbon shorts that might result from cell crush or a manufacturing defect

  3. Field Experiments on 10 kV Switching Shunt Capacitor Banks Using Ordinary and Phase-Controlled Vacuum Circuit Breakers

    Directory of Open Access Journals (Sweden)

    Wenxia Sima

    2016-01-01

    Full Text Available During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor banks. An analytical analysis for switching 10 kV shunt capacitor banks is presented on the basis of a reduced circuit with an ungrounded neutral. A phase selection strategy for VCBs to switch 10 kV shunt capacitor banks is proposed. Switching on current waveforms and switching off overvoltage waveforms with, and without, phase selection were measured and discussed by field experiments in a 110 kV substation in Chongqing, China. Results show that the operation of phase-controlled VCBs for 10 kV switching shunt capacitor banks is stable, and phase-controlled VCBs can be used to implement the 10 kV switching on/off shunt capacitor banks to limit the transient overvoltage and overcurrent. The values of overvoltage and inrush current using phase-controlled VCBs are all below those with ordinary VCBs.

  4. Broadband hitless silicon electro-optic switch for on-chip optical networks.

    Science.gov (United States)

    Lira, Hugo L R; Manipatruni, Sasikanth; Lipson, Michal

    2009-12-01

    We report on the demonstration of a broadband (60 GHz), spectrally hitless, compact (20 microm x 40 microm), fast (7 ns) electro-optical switch. The device is composed of two coupled resonant cavities, each with an independently addressable PIN diode. This topology enables operation of the switch without perturbing adjacent channels in a wavelength division multiplexing (WDM) system. PMID:20052150

  5. A compact plasmonic MOS-based 2x2 electro-optic switch

    CERN Document Server

    Ye, Chenran; Soref, Richard A; Sorger, Volker J

    2015-01-01

    We report on a three-waveguide electro-optic switch for compact photonic integrated circuits and data routing applications. The device features a plasmonic metal-oxide-semiconductor (MOS) mode for enhanced light-matter-interactions. The switching mechanism originates from a capacitor-like design where the refractive index of the active medium, Indium-Tin-Oxide, is altered via shifting the plasma frequency due to carrier accumulation inside the waveguide-based MOS structure. This light manipulation mechanism controls the transmission direction of transverse magnetic polarized light into either a CROSS or BAR waveguide port. The extinction ratio of 18 dB (7) dB for the CROSS (BAR) state, respectively, is achieved via a gating voltage bias. The ultrafast broadband fJ/bit device allows for seamless integration with Siliconon- Insulator platforms to for low-cost manufacturing.

  6. A compact plasmonic MOS-based 2×2 electro-optic switch

    Science.gov (United States)

    Ye, Chenran; Liu, Ke; Soref, Richard A.; Sorger, Volker J.

    2015-01-01

    We report on a three-waveguide electro-optic switch for compact photonic integrated circuits and data routing applications. The device features a plasmonic metal-oxide-semiconductor (MOS) mode for enhanced light-matter-interactions. The switching mechanism originates from a capacitor-like design where the refractive index of the active medium, indium-tin-oxide, is altered via shifting the plasma frequency due to carrier accumulation inside the waveguide-based MOS structure. This light manipulation mechanism controls the transmission direction of transverse magnetic polarized light into either a CROSS or BAR waveguide port. The extinction ratio of 18 (7) dB for the CROSS (BAR) state, respectively, is achieved via a gating voltage bias. The ultrafast broadband fJ/bit device allows for seamless integration with silicon-on-insulator platforms for low-cost manufacturing.

  7. Fully reconfigurable 2x2 optical cross-connect using tunable wavelength switching modules

    DEFF Research Database (Denmark)

    Liu, Fenghai; Zheng, Xueyan; Pedersen, Rune Johan Skullerud;

    2001-01-01

    A modular tunable wavelength switching module is proposed and used to construct 2x2 fully reconfigurable optical cross-connects. Large size optical switch is avoided in the OXC and it is easy to upgrade to more wavelength channels.......A modular tunable wavelength switching module is proposed and used to construct 2x2 fully reconfigurable optical cross-connects. Large size optical switch is avoided in the OXC and it is easy to upgrade to more wavelength channels....

  8. Integrated optical switching based on the protein bacteriorhodopsin.

    Science.gov (United States)

    Dér, András; Valkai, Sándor; Fábián, László; Ormos, Pál; Ramsden, Jeremy J; Wolff, Elmar K

    2007-01-01

    According to our earlier pioneering study, a dry film containing native bacteriorhodopsin (bR) shows unique nonlinear optical properties (refractive index change, controllable by light of different colors, greater than 2 x 10(-3)) that are in many respects superior to those of the materials presently applied in integrated optics. Here, we report on the first integrated optical application based on a miniature Mach-Zehnder interferometer (see Figs. 1 and 2) demonstrating a real switching effect by bR (efficiency higher than 90%) due to the M-state. Our results also imply that the refractive index change of the K-state (9 x 10(-4)) is high enough for fast switching. PMID:17132043

  9. Casimir switch: steering optical transparency with vacuum forces

    CERN Document Server

    Liu, X -f; Jing, H

    2016-01-01

    The Casimir force, originating from vacuum zero-point energy, is one of the most intriguing purely quantum effects. It has attracted renewed interests in current field of nanomechanics, due to the rapid size decrease of on-chip devices. Here we study the optomechanically-induced transparency (OMIT) with a tunable Casimir force. We find that the optical output rate can be significantly altered by the vacuum force, even terminated and then restored, indicating a highly-controlled optical switch. Our result addresses the possibility of designing exotic optical nano-devices by harnessing the power of vacuum.

  10. Simulation of the Physical Performance of Optical Packet Switching Nodes

    Institute of Scientific and Technical Information of China (English)

    王春华; 李力; 等

    2002-01-01

    A graphical and visual simulation system for the study of optical packet switching(OPS)nodes is accomplished.With the simulation system,the effect on physical performance-bit error rate(BER)due to a variety of factors such as the crosstalk parameters of OPS nodes,number of cascaded OPS nodes,length of optical output buffer,traffic load and fluctuation of amplitude of optical signals are evaluated.Reliability of the simulation system is proved by the analytical results obtained in all the above cases.

  11. Casimir switch: steering optical transparency with vacuum forces

    Science.gov (United States)

    Liu, Xi-Fang; Li, Yong; Jing, H.

    2016-06-01

    The Casimir force, originating from vacuum zero-point energy, is one of the most intriguing purely quantum effects. It has attracted renewed interests in current field of nanomechanics, due to the rapid size decrease of on-chip devices. Here we study the optomechanically-induced transparency (OMIT) with a tunable Casimir force. We find that the optical output rate can be significantly altered by the vacuum force, even terminated and then restored, indicating a highly-controlled optical switch. Our result addresses the possibility of designing exotic optical nano-devices by harnessing the power of vacuum.

  12. Wireless electro-optic switching network for optical fiber sensor array using MEMS-IDT devices

    Science.gov (United States)

    Varadan, Vijay K.; Varadan, Vasundara V.

    1999-09-01

    Optical fiber arrays have been proposed for signal paths in various civilian and military controls as a means of offering advanced sensing functions not available in electronic systems. To implement optic fiber sensors on various control systems, a proper electro-optic architecture (EOA) with a bar- coded electro-optical switch needs to be studied. In this paper, a design of such EO switch is proposed which can be operated remotely. Lithium Niobate is chosen as the EO material. The MEMS-IDT device is designed with Lithium Niobate as a substrate with IDT and a set of floating reflectors. The reflectors can be programmable and thus a bar-coded switch can be fabricated. The electrostatic field between the reflectors and the Lithium Niobate serves as the fast acting switch in this application.

  13. Experimental and theoretical investigation of semiconductor optical amplifier (SOA) based all-optical switches

    DEFF Research Database (Denmark)

    Nielsen, Mads Lønstrup

    2004-01-01

    , consisting of an SOA and an asymmetric MZI filter, is analyzed in the small-signal regime, and the obtainable modulation bandwidth is expressed analytically. A new optical spectrum approach to small signal analysis is introduced, and is used to assess the bandwidth enhancing effect of different optical......This thesis analyzes semiconductor optical amplifier (SOA) based all-optical switches experimentally and through numerical simulations. These devices are candidates for optical signal processing functionalities such as wavelength conversion, regeneration, and logic processing in future transparent...... optical networks. The factors governing the modulation bandwidth of SOAs are determined, and schemes for reducing detrimental patterning effects are discussed. Three types of SOA-based switches are investigated numerically: so-called standardmode and differential-mode switches, and the filtering assisted...

  14. Optimizing POF/PCF based optical switch for indoor LAN

    Science.gov (United States)

    Bhuiyan, M. M. I.; Rashid, M. M.; Ahmed, Sayem; Bhuiyan, M.; Kajihara, M.

    2013-12-01

    For indoor local area network (LAN) the Polymer optical fiber (POF) is mostly appropriate, because of its large core diameter and flexible material. A 1×2 optical switch for indoor LAN using POF and a shape memory alloy (SMA) coil actuator with magnetic latches was successfully fabricated and tested. To achieve switching by the movement of a POF, large displacement is necessary because the core diameter is large (e.g., 0.486mm). A SMA coil actuator is used for large displacement and a magnetic latching system is used for fixing the position of the shifted POF. The insertion loss is 0.40 to 0.50dB and crosstalk is more than 50dB without index-matching oil. Switching speed is less than 1s at a driving current of 80mA. A cycling test was performed 1.4 million times. Polymer clad fiber optical (PCF) switch also fabricated and tasted.

  15. Design of parity generator and checker circuit using electro-optic effect of Mach-Zehnder interferometers

    Science.gov (United States)

    Kumar, Santosh; Chanderkanta; Amphawan, Angela

    2016-04-01

    Parity is an extra bit which is used to add in digital information to detect error at the receiver end. It can be even and odd parity. In case of even parity, the number of one's will be even included the parity and reverse in the case of odd parity. The circuit which is used to generate the parity at the transmitter side, called the parity generator and the circuit which is used to detect the parity at receiver side is called as parity checker. In this paper, an even and odd parity generator and checker circuits are designed using electro-optic effect inside lithium niobate based Mach-Zehnder Interferometers (MZIs). The MZIs structures collectively show powerful capability in switching an input optical signal to a desired output port from a collection of output ports. The paper constitutes a mathematical description of the proposed device and thereafter simulation using MATLAB. The study is verified using beam propagation method (BPM).

  16. Deterministic linear optics quantum computation utilizing linked photon circuits

    CERN Document Server

    Yoran, N; Yoran, Nadav; Reznik, Benni

    2003-01-01

    We suggest an efficient scheme for quantum computation with linear optical elements utilizing "linked" photon states. The linked states are designed according to the particular quantum circuit one wishes to process. Once a linked-state has been successfully prepared, the computation is pursued deterministically by a sequence of teleportation steps. The present scheme enables a significant reduction of the average number of elementary gates per logical gate to about 20-30 CZ_{9/16} gates.

  17. Ultrafast polarization optical switch constructed from one-dimensional photonic crystal and its performance analysis

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; LI Qing; GAO DingShan

    2009-01-01

    All-optical switch with the ultrafast optical switching rate is a key device in the next generation optical network. In this article, we propose a polarization switch with ps switching time, which is constructed from one-dimensional resonant photonic crystal (1D RPC). The model of switch operating at 1.5 μm is established based on the optical stark effect (OSE). We calculate the performance indices of the switch and the influences of errors of periods and refractive index on the performance characteristics.

  18. Design and analysis of optical burst-switched networks

    Science.gov (United States)

    Xiong, Yijun; Vandenhoute, Marc; Cankaya, Hakki C.

    1999-08-01

    Optical burst switching (OBS) is a promising solution for building terabit optical routers and realizing IP over D- WDM. In this paper, we describe the basic concept of OBS and a general architecture of optical routers. The key design issues related to the OBS are discussed, notably, burstification, offset-time management and channel scheduling. A simple channel scheduling algorithm called LAUC (Latest Available Unscheduled Channel) algorithm is presented, which is also called Horizon algorithm in the literature. The performance of optical routers under random and self-similar traffic is thoroughly studied via computer simulations. Our study indicates that the distribution of burst length is not exponential any more. For the FDL (fiber delay line) optical buffer, the burst loss ratio is quite sensitive to the traffic characteristic of bursts when using the LAUC algorithm.

  19. Electro-optic switching based on a waveguide-ring resonator made of dielectric-loaded graphene plasmon waveguides

    Science.gov (United States)

    Qi, Zhe; Zhu, Zhi Hong; Xu, Wei; Zhang, Jian Fa; Cai Guo, Chu; Liu, Ken; Yuan, Xiao Dong; Qiao Qin, Shi

    2016-09-01

    We numerically demonstrate that electro-optic switching in the mid-infrared range can be realized using a waveguide-ring resonator made of dielectric-loaded graphene plasmon waveguides (DLGPWs). The numerical results are in good agreement with the results of physical analysis. The switching mechanism is based on dynamic modification of the resonant wavelengths of the ring resonator, achieved by varying the Fermi energy of a graphene sheet. The results reveal that a switching ratio of ∼24 dB can be achieved with only a 0.01 eV change in the Fermi energy. Such electrically controlled switching operation may find use in actively tunable integrated photonic circuits.

  20. Two-dimensional design and analysis of trench-coupler based Silicon Mach-Zehnder thermo-optic switch.

    Science.gov (United States)

    Liu, Ke; Zhang, Chenglong; Mu, Sixuan; Wang, Shuang; Sorger, Volker J

    2016-07-11

    Optical switches are key components for routing of light transmission paths in data links. Existing waveguide-based Mach-Zehnder interferometer (MZI) switches occupy a significant amount of real estate on-chip. Here we propose a compact Silicon MZI thermo-optic 2 × 2 photonic switch, consisting of two frustrated total internal reflection (TIR) trench couplers and TIR mirror-based 90° waveguide bends, forming a rectangular MZI configuration. The switch allows for reconfigurable design footprints due to selected control of the optical signal being transmitted and reflected at the 90° crosses and bends. Our analysis results show that the switch exhibits a chip size of 42 µm × 42 µm, the extinction ratio of ~14 dB, the rise and fall time of 20 μs and 16 μs, and the low switching voltage and power of 0.35 V and 26 mW, respectively. This device configuration can readily scale its pattern at the two-dimensional directions, making them attractive for Silicon photonic integrated circuits. PMID:27410854

  1. Brain Circuit for Cognitive Control is Shared by Task and Language Switching.

    Science.gov (United States)

    De Baene, Wouter; Duyck, Wouter; Brass, Marcel; Carreiras, Manuel

    2015-09-01

    Controlling multiple languages during speech production is believed to rely on functional mechanisms that are (at least partly) shared with domain-general cognitive control in early, highly proficient bilinguals. Recent neuroimaging results have indeed suggested a certain degree of neural overlap between language control and nonverbal cognitive control in bilinguals. However, this evidence is only indirect. Direct evidence for neural overlap between language control and nonverbal cognitive control can only be provided if two prerequisites are met: Language control and nonverbal cognitive control should be compared within the same participants, and the task requirements of both conditions should be closely matched. To provide such direct evidence for the first time, we used fMRI to examine the overlap in brain activation between switch-specific activity in a linguistic switching task and a closely matched nonlinguistic switching task, within participants, in early, highly proficient Spanish-Basque bilinguals. The current findings provide direct evidence that, in these bilinguals, highly similar brain circuits are involved in language control and domain-general cognitive control.

  2. Influence of a Circuit Breaker's Grading Capacitor on Controlled Transformer Switching

    Science.gov (United States)

    Corrodi, Yves; Kamei, Kenji; Kohyama, Haruhiko; Ito, Hiroki

    Controlled switching, taking into account the residual flux level within a transformer core, can effectively eliminate inrush currents. Many switching sequences assume the residual flux as a constant value, which can be obtained by a measurement after a transformer de-energization. However, in case of a transformer system that is switched by a circuit breaker equipped with a grading capacitor, the residual flux characteristic cannot be considered as constant. A source voltage will feed the deenergized transformer system through the grading capacitor, which will change the residual flux level and let oscillations appear. It follows that the optimal re-energization targets change and inrush currents might not be optimally minimized. Further, transient voltages based on line failures can influence the residual flux through a grading capacitor as well. At first, this paper evaluates the influence of a grading capacitor on the residual flux characteristic analytically. Further, measurements of two transformer systems at a varied de-energization instant and for different grading capacitors provide actual information for the development of future controller systems.

  3. High-Resolution Mammography Detector Employing Optical Switching Readout

    Science.gov (United States)

    Irisawa, Kaku; Kaneko, Yasuhisa; Yamane, Katsutoshi; Sendai, Tomonari; Hosoi, Yuichi

    Conceiving a new detector structure, FUJIFILM Corporation has successfully put its invention of an X-ray detector employing "Optical Switching" into practical use. Since Optical Switching Technology allows an electrode structure to be easily designed, both high resolution of pixel pitch and low electrical noise readout have been achieved, which have consequently realized the world's smallest pixel size of 50×50 μm2 from a Direct-conversion FPD system as well as high DQE. The digital mammography system equipped with this detector enables to acquire high definition images while maintaining granularity. Its outstanding feature is to be able to acquire high-precision images of microcalcifications which is an important index in breast examination.

  4. Silicon Modulators, Switches and Sub-systems for Optical Interconnect

    Science.gov (United States)

    Li, Qi

    Silicon photonics is emerging as a promising platform for manufacturing and integrating photonic devices for light generation, modulation, switching and detection. The compatibility with existing CMOS microelectronic foundries and high index contrast in silicon could enable low cost and high performance photonic systems, which find many applications in optical communication, data center networking and photonic network-on-chip. This thesis first develops and demonstrates several experimental work on high speed silicon modulators and switches with record performance and novel functionality. A 8x40 Gb/s transmitter based on silicon microrings is first presented. Then an end-to-end link using microrings for Binary Phase Shift Keying (BPSK) modulation and demodulation is shown, and its performance with conventional BPSK modulation/ demodulation techniques is compared. Next, a silicon traveling-wave Mach- Zehnder modulator is demonstrated at data rate up to 56 Gb/s for OOK modulation and 48 Gb/s for BPSK modulation, showing its capability at high speed communication systems. Then a single silicon microring is shown with 2x2 full crossbar switching functionality, enabling optical interconnects with ultra small footprint. Then several other experiments in the silicon platform are presented, including a fully integrated in-band Optical Signal to Noise Ratio (OSNR) monitor, characterization of optical power upper bound in a silicon microring modulator, and wavelength conversion in a dispersion-engineered waveguide. The last part of this thesis is on network-level application of photonics, specically a broadcast-and-select network based on star coupler is introduced, and its scalability performance is studied. Finally a novel switch architecture for data center networks is discussed, and its benefits as a disaggregated network are presented.

  5. Reactive and proactive routing in labelled optical burst switching networks

    OpenAIRE

    Klinkowski, Miroslaw; Careglio, Davide; Solé Pareta, Josep

    2009-01-01

    Optical burst switching architectures without buffering capabilities are sensitive to burst congestion. The existence of a few highly congested links may seriously aggravate the network throughput. Proper network routing may help in congestion reduction. The authors focus on adaptive routing strategies to be applied in labelled OBS networks, that is, with explicit routing paths. In particular, two isolated alternative routing algorithms that aim at network performance improvement because o...

  6. Electro-optical switching by liquid-crystal controlled metasurfaces

    CERN Document Server

    Decker, Manuel; Minovich, Alexander; Staude, Isabelle; Miroshnichenko, Andrey E; Chigrin, Dmitry; Neshev, Dragomir N; Jagadish, Chennupati; Kivshar, Yuri S

    2013-01-01

    We study the optical response of a metamaterial surface created by a lattice of split-ring resonators covered with a nematic liquid crystal and demonstrate millisecond timescale switching between electric and magnetic resonances of the metasurface. This is achieved due to a high sensitivity of liquid-crystal molecular reorientation to the symmetry of the metasurface as well as to the presence of a bias electric field. Our experiments are complemented by numerical simulations of the liquid-crystal reorientation.

  7. Electro-optical switching by liquid-crystal controlled metasurfaces.

    Science.gov (United States)

    Decker, Manuel; Kremers, Christian; Minovich, Alexander; Staude, Isabelle; Miroshnichenko, Andrey E; Chigrin, Dmitry; Neshev, Dragomir N; Jagadish, Chennupati; Kivshar, Yuri S

    2013-04-01

    We study the optical response of a metamaterial surface created by a lattice of split-ring resonators covered with a nematic liquid crystal and demonstrate millisecond timescale switching between electric and magnetic resonances of the metasurface. This is achieved due to a high sensitivity of liquid-crystal molecular reorientation to the symmetry of the metasurface as well as to the presence of a bias electric field. Our experiments are complemented by numerical simulations of the liquid-crystal reorientation. PMID:23571978

  8. Electro-optical switching by liquid-crystal controlled metasurfaces

    OpenAIRE

    Decker, Manuel; Kremers, Christian; Minovich, Alexander; Staude, Isabelle; Miroshnichenko, Andrey E.; Chigrin, Dmitry; Neshev, Dragomir N.; Jagadish, Chennupati; Kivshar, Yuri S.

    2013-01-01

    We study the optical response of a metamaterial surface created by a lattice of split-ring resonators covered with a nematic liquid crystal and demonstrate millisecond timescale switching between electric and magnetic resonances of the metasurface. This is achieved due to a high sensitivity of liquid-crystal molecular reorientation to the symmetry of the metasurface as well as to the presence of a bias electric field. Our experiments are complemented by numerical simulations of the liquid-cry...

  9. Magneto-optical switching devices based on Si resonators

    Science.gov (United States)

    Noda, Kazuki; Okada, Kazuya; Amemiya, Yoshiteru; Yokoyama, Shin

    2016-04-01

    The magneto-optical switching devices based on Si ring and Si photonic crystal resonators have been fabricated using a Bi3Fe5O12 (BIG) film deposited by the metal organic decomposition (MOD) method. The quality of the obtained BIG film was evaluated by X-ray diffraction and the magneto-optical Kerr effect and relatively good results were obtained. The light modulations of both devices were ≦20% at a wavelength of ˜1.5 µm. The operation mechanisms of both devices are explained by the Cotton-Mouton effect where the magnetic field direction is perpendicular to the light propagation direction.

  10. Atom-loss-induced quantum optical bi-stability switch

    Institute of Scientific and Technical Information of China (English)

    Wu Bao-Jun; Cui Fu-Cheng

    2012-01-01

    We investigate the nonlinear dynamics of a system composed of a cigar-shaped Bose-Einstein condensate and an optical cavity with the two sides coupled dispersively.By adopting discrete-mode approximation for the condensate,taking atom loss as a necessary part of the model to analyze the evolution of the system,while using trial and errormethod to find out steady states of the system as a reference,numerical simulation demonstrates that with a constant pump,atom loss will trigger a quantum optical bi-stability switch,which predicts a new interesting phenomenon for experiments to verify.

  11. Plasmonic nanopatch array for optical integrated circuit applications.

    Science.gov (United States)

    Qu, Shi-Wei; Nie, Zai-Ping

    2013-01-01

    Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will definitely be more efficient than isolated nanoantennas. In this article, the concepts of microwave antenna arrays are applied to efficiently convert plasmonic waves in the plasmonic waveguides into free-space optical waves or vice versa. The proposed plasmonic nanoantenna array, with nanopatch antennas and a coupled wedge plasmon waveguide, can also act as an efficient spectrometer to project different wavelengths into different directions, or as a spatial filter to absorb a specific wavelength at a specified incident angle. PMID:24201454

  12. Plasmonic nanopatch array for optical integrated circuit applications.

    Science.gov (United States)

    Qu, Shi-Wei; Nie, Zai-Ping

    2013-11-08

    Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will definitely be more efficient than isolated nanoantennas. In this article, the concepts of microwave antenna arrays are applied to efficiently convert plasmonic waves in the plasmonic waveguides into free-space optical waves or vice versa. The proposed plasmonic nanoantenna array, with nanopatch antennas and a coupled wedge plasmon waveguide, can also act as an efficient spectrometer to project different wavelengths into different directions, or as a spatial filter to absorb a specific wavelength at a specified incident angle.

  13. Plasmonic nanopatch array for optical integrated circuit applications

    Science.gov (United States)

    Qu, Shi-Wei; Nie, Zai-Ping

    2013-01-01

    Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will definitely be more efficient than isolated nanoantennas. In this article, the concepts of microwave antenna arrays are applied to efficiently convert plasmonic waves in the plasmonic waveguides into free-space optical waves or vice versa. The proposed plasmonic nanoantenna array, with nanopatch antennas and a coupled wedge plasmon waveguide, can also act as an efficient spectrometer to project different wavelengths into different directions, or as a spatial filter to absorb a specific wavelength at a specified incident angle. PMID:24201454

  14. Separation and insertion of optical bit-serial label in optical packet switching

    Institute of Scientific and Technical Information of China (English)

    Yun Ling; Kun Qiu; Mian Zheng

    2006-01-01

    @@ The bipolar phase-shift-keying (BPSK) optical orthogonal codes (OOCs) are inserted into the optical packet format of bit-serial label. The ultra-fast separation of the label and payload is performed through the auto-correlation pulses indicating the time position at which the optical switch changes the state.The insertion of the new label can also be realized by detecting the auto-correlation pulse at the line rate. Especially, the scheme can be adapted to the asynchronous separation and insertion and realize the variable-length packet switching. The results of simulation verify the feasibility of the scheme.

  15. A Biological-Realtime Neuromorphic System in 28 nm CMOS using Low-Leakage Switched Capacitor Circuits

    OpenAIRE

    Mayr, Christian; Partzsch, Johannes; Noack, Marko; Hänzsche, Stefan; Scholze, Stefan; Höppner, Sebastian; Ellguth, Georg; Schüffny, Rene

    2014-01-01

    A switched-capacitor (SC) neuromorphic system for closed-loop neural coupling in 28 nm CMOS is presented, occupying 600 um by 600 um. It offers 128 input channels (i.e. presynaptic terminals), 8192 synapses and 64 output channels (i.e. neurons). Biologically realistic neuron and synapse dynam- ics are achieved via a faithful translation of the behavioural equations to SC circuits. As leakage currents significantly affect circuit behaviour at this technology node, dedicated compensation techni...

  16. A novel all-optical label processing based on multiple optical orthogonal codes sequences for optical packet switching networks

    Science.gov (United States)

    Zhang, Chongfu; Qiu, Kun; Xu, Bo; Ling, Yun

    2008-05-01

    This paper proposes an all-optical label processing scheme that uses the multiple optical orthogonal codes sequences (MOOCS)-based optical label for optical packet switching (OPS) (MOOCS-OPS) networks. In this scheme, each MOOCS is a permutation or combination of the multiple optical orthogonal codes (MOOC) selected from the multiple-groups optical orthogonal codes (MGOOC). Following a comparison of different optical label processing (OLP) schemes, the principles of MOOCS-OPS network are given and analyzed. Firstly, theoretical analyses are used to prove that MOOCS is able to greatly enlarge the number of available optical labels when compared to the previous single optical orthogonal code (SOOC) for OPS (SOOC-OPS) network. Then, the key units of the MOOCS-based optical label packets, including optical packet generation, optical label erasing, optical label extraction and optical label rewriting etc., are given and studied. These results are used to verify that the proposed MOOCS-OPS scheme is feasible.

  17. Switching from positive to negative absorption with electromagnetically induced transparency in circuit quantum electrodynamics

    International Nuclear Information System (INIS)

    We present a theoretical study of electromagnetically induced transparency (EIT) in a superconducting quantum circuit with a tunable V-shaped energy spectrum derived from two superconducting Josephson charge qubits coupled with each other through a superconducting quantum interference device. Using the density matrix formalism and the steady-state approximation, we obtain the analytical expressions of the first-order matrix element associated with the absorption and dispersion of the probe field for two different V-type schemes. Our results show that, for this superconducting quantum system, it is possible to realize a remarkable phenomenon that dynamic conversion between EIT and EIT with amplification without population inversion. Such a unique optical feature has potential applications in quantum optical devices and quantum information processing. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  18. Dynamical behaviors of a system with switches between the R(o)ssler oscillator and Chua circuits

    Institute of Scientific and Technical Information of China (English)

    Zhang Chun; Yu Yue; Han Xiu-Jing; Bi Qin-Sheng

    2012-01-01

    The behaviors of a system that alternates between the R(o)ssler oscillator and Chua's circuit is investigated to explore the influence of the switches on the dynamical evolution.Switches related to the state variables are introduced,upon which a typical switching dynamical model is established.Bifurcation sets of the subsystems are derived via analysis of the related equilibrium points,which divide the parameters into several regions corresponding to different types of attractors.The dynamics behave typically in period orbits with the variation of the parameters.The focus/cycle periodic switching phenomenon is explored in detail to present the mechanism of the movement.The period-doubling bifurcation to chaos can be observed via the doubling increase of the turning points related to the switches.Furthermore,period-decreasing sequences have been obtained,which can be explained by the variation of the eigenvalues associated with the equilibrium points of the subsystems.

  19. A novel optical burst switching architecture for high speed networks

    Institute of Scientific and Technical Information of China (English)

    Amit Kumar Garg; R. S. Kaler

    2008-01-01

    A novel optical burst switching (OBS) high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time (JET) signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-priorconfirrnation-packet (SPCP) is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes (e.g., orthogonal optical codes (OOC)),which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing.

  20. International standards for optical circuit board fabrication, assembly and measurement

    Science.gov (United States)

    Pitwon, Richard; Immonen, Marika; Wang, Kai; Itoh, Hideo; Shioda, Tsuyoshi; Wu, Jinhua; Zhu, Long Xiu; Yan, Hui Juan; Worrall, Alex

    2016-03-01

    The commercial adoption of electro-optical printed circuit board (EOCB) technology will be accelerated by the development of industrial and conformity standards for high volume fabrication, connector assembly and waveguide measurement. In this paper, we introduce international standardisation activities surrounding EOCBs and report on industrial processes developed for the high volume fabrication of complex EOCBs with embedded multimode polymer waveguides including a first connector standard for polymer waveguide termination. We focus on solving a serious historic problem with the measurement of optical waveguide systems, namely the lack of harmonised measurement conditions for optical waveguides, which to this day gives rise to strong inconsistencies in the results of measurements by different parties on the same waveguide. We report on the development of a standard to ensure repeatable measurement of optical waveguides, whereby we demonstrate how the application of a measurement identification system and proposed reference measurement conditions can bring variation in measurement results to within 5%, thereby serving as the basis for a formal reliable optical waveguide measurement methodology.

  1. Border collision bifurcations in a two-dimensional piecewise smooth map from a simple switching circuit.

    Science.gov (United States)

    Gardini, Laura; Fournier-Prunaret, Danièle; Chargé, Pascal

    2011-06-01

    In recent years, the study of chaotic and complex phenomena in electronic circuits has been widely developed due to the increasing number of applications. In these studies, associated with the use of chaotic sequences, chaos is required to be robust (not occurring only in a set of zero measure and persistent to perturbations of the system). These properties are not easy to be proved, and numerical simulations are often used. In this work, we consider a simple electronic switching circuit, proposed as chaos generator. The object of our study is to determine the ranges of the parameters at which the dynamics are chaotic, rigorously proving that chaos is robust. This is obtained showing that the model can be studied via a two-dimensional piecewise smooth map in triangular form and associated with a one-dimensional piecewise linear map. The bifurcations in the parameter space are determined analytically. These are the border collision bifurcation curves, the degenerate flip bifurcations, which only are allowed to occur to destabilize the stable cycles, and the homoclinic bifurcations occurring in cyclical chaotic regions leading to chaos in 1-piece.

  2. A fast nonlinear variable structure equivalent magnetic circuit modeling for dual-channel switched reluctance machine

    International Nuclear Information System (INIS)

    Switched reluctance machines (SRMs) are normally designed and applied as 6/4 or 8/6 single-channel SRMs, recent efforts with 12/8 dual-channel SRM (DCSRM) have spurred interest. The DCSRM is driven by two independent sets of power electronic circuits with dual control channels and a fault tolerated operation mode can be used in this system for high reliability. In this paper, a fast nonlinear variable structure equivalent magnetic circuit (VSEMC) modeling method is developed for DCSRM. This method is used to calculate the static self and mutual flux linkage of phase winding for DCSRM by the formulas of airgap permeances, the stator and rotor pole and yoke permeances, in which the mutual effects as well as the magnetic saturation are taken into account. Then, a series of experimental tests are performed to obtain the static magnetic characteristics of a 12/8 DCSRM including self and mutual flux linkages under different rotor positions for varying exciting current conditions. The effectiveness of this proposed VSEMC method is verified by comparing with the FEM analysis and experimental results. Finally, details of simulation model for DCSRM under single channel operation mode and dual channel operation mode and comparison with experimental waveforms along with their implications for performances prediction are presented.

  3. Monolithic, High-Speed Fiber-Optic Switching Array for Lidar Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed optical device is a fiber-based multi-channel switch to quickly switch a fiber-coupled laser among many possible output channels to create a...

  4. Electro-optical circuit board with single-mode glass waveguide optical interconnects

    Science.gov (United States)

    Brusberg, Lars; Neitz, Marcel; Pernthaler, Dominik; Weber, Daniel; Sirbu, Bogdan; Herbst, Christian; Frey, Christopher; Queisser, Marco; Wöhrmann, Markus; Manessis, Dionysios; Schild, Beatrice; Oppermann, Hermann; Eichhammer, Yann; Schröder, Henning; Hâkansson, Andreas; Tekin, Tolga

    2016-03-01

    A glass optical waveguide process has been developed for fabrication of electro-optical circuit boards (EOCB). Very thin glass panels with planar integrated single-mode waveguides can be embedded as a core layer in printed circuit boards for high-speed board-level chip-to-chip and board-to-board optical interconnects over an optical backplane. Such singlemode EOCBs will be needed in upcoming high performance computers and data storage network environments in case single-mode operating silicon photonic ICs generate high-bandwidth signals [1]. The paper will describe some project results of the ongoing PhoxTroT project, in which a development of glass based single-mode on-board and board-to-board interconnection platform is successfully in progress. The optical design comprises a 500 μm thin glass panel (Schott D263Teco) with purely optical layers for single-mode glass waveguides. The board size is accommodated to the mask size limitations of the fabrication (200 mm wafer level process, being later transferred also to larger panel size). Our concept consists of directly assembling of silicon photonic ICs on cut-out areas in glass-based optical waveguide panels. A part of the electrical wiring is patterned by thin film technology directly on the glass wafer surface. A coupling element will be assembled on bottom side of the glass-based waveguide panel for 3D coupling between board-level glass waveguides and chip-level silicon waveguides. The laminate has a defined window for direct glass access for assembling of the photonic integrated circuit chip and optical coupling element. The paper describes the design, fabrication and characterization of glass-based electro-optical circuit board with format of (228 x 305) mm2.

  5. Dynamic feedback circuits function as a switch for shaping a maturation-inducing steroid pulse in Drosophila

    DEFF Research Database (Denmark)

    Møller, Morten Erik; Danielsen, Erik Thomas; Herder, Rachel;

    2013-01-01

    the decline in ecdysone levels required to produce a temporal steroid pulse that drives developmental progression to adulthood. The feedback circuits rely on a developmental switch in the expression of Broad isoforms that transcriptionally activate or silence components in the ecdysone biosynthetic...

  6. Calculation of critical time for short circuit current switch-off considering salient pole design of synchronous generators

    OpenAIRE

    Podymaka, Valerii I.; Novohretskyi, Serhii M.

    2014-01-01

    The dynamic stability calculation method of the parallel operation of the marine synchronous generators is examined. The improved calculations algorithm of the critical time of the short circuit switch-off is offeted which takes into account salient-pole rotor of the synchronous generator. The results of calculations which prove efficiency of using the proposed algorithm, are presented.

  7. All-optical switching of magnetoresistive devices using telecom-band femtosecond laser

    Energy Technology Data Exchange (ETDEWEB)

    He, Li; Chen, Jun-Yang; Wang, Jian-Ping, E-mail: jpwang@umn.edu, E-mail: moli@umn.edu; Li, Mo, E-mail: jpwang@umn.edu, E-mail: moli@umn.edu [Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-09-07

    Ultrafast all-optical switching of the magnetization of various magnetic systems is an intriguing phenomenon that can have tremendous impact on information storage and processing. Here, we demonstrate all-optical switching of GdFeCo alloy films using a telecom-band femtosecond fiber laser. We further fabricate Hall cross devices and electrically readout all-optical switching by measuring anomalous Hall voltage changes. The use of a telecom laser and the demonstrated all-optical switching of magnetoresistive devices represent the first step toward integration of opto-magnetic devices with mainstream photonic devices to enable novel optical and spintronic functionalities.

  8. All-optical switching of magnetoresistive devices using telecom-band femtosecond laser

    International Nuclear Information System (INIS)

    Ultrafast all-optical switching of the magnetization of various magnetic systems is an intriguing phenomenon that can have tremendous impact on information storage and processing. Here, we demonstrate all-optical switching of GdFeCo alloy films using a telecom-band femtosecond fiber laser. We further fabricate Hall cross devices and electrically readout all-optical switching by measuring anomalous Hall voltage changes. The use of a telecom laser and the demonstrated all-optical switching of magnetoresistive devices represent the first step toward integration of opto-magnetic devices with mainstream photonic devices to enable novel optical and spintronic functionalities

  9. 160 Gbit/s optical packet switching using a silicon chip

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Galili, Michael;

    2012-01-01

    We have successfully demonstrated 160 Gbit/s all-optical packet switching based on cross-phase modulation using a silicon chip. Error free performance is achieved for the 4-to-1 switched 160 Gbit/s packet.......We have successfully demonstrated 160 Gbit/s all-optical packet switching based on cross-phase modulation using a silicon chip. Error free performance is achieved for the 4-to-1 switched 160 Gbit/s packet....

  10. Optimum design of phase opposition disposition pulse width modulation logic circuit for switching seven level cascaded half bridge inverter

    Directory of Open Access Journals (Sweden)

    Nentawe Y. Goshwe

    2016-06-01

    Full Text Available Theevolution of multilevel inverters (MLIs has made it possible to extract power from direct current (DC sources to alternating current (AC power. This paper presents the design of a novel phase opposition disposition pulse width modulation scheme (PODPWM logic circuit for a conventional single phase seven level cascaded H-Bridge (CHB inverter using Matlab/Simulink. The minimum switching logic circuit for the single phase seven level CHB inverter was obtained by modeling the logic equations that could be used with any number of levels depending on the number of modulating and carrier signals involved. The reduction in total harmonic distortion (THD of the output voltage for the MLI using low switching frequency at different modulation indixes is also investigated. The logic equations have made it easier to design a PODPWM circuit for any CHB inverter and the logic gates designed gave an optimum THD value of 16.73 % at modulation index of 0.20.

  11. Study of Crosstalk propoerty in an Optical Packet Switching Node

    Institute of Scientific and Technical Information of China (English)

    王春华; 李力; 等

    2002-01-01

    The effect of queuing delay of output buffer on the crosstalk property in optical packel switching nodes in investigated.The relationship between crosstalk and buffer length is obtained.From the calculation and simulation results,it is concluded that the corsstalk power penalty predominantly depends on the buffer length,the longer the buffer,the greater the penalty,as well as the random range of the penalty.While comparing with the effect of queuing delay,the effect of random routing path delay takes very little proportion in the total power penalty.

  12. Optical switch phenomenon in a self-defocusing medium

    Institute of Scientific and Technical Information of China (English)

    Huagang Li; Zhihua Luo

    2009-01-01

    A spatial optical switch phenomenon caused by the induced focusing of a weak probe beam occurring in self-defocusing nonlinear media is discussed theoretically.A weak beam is induced to focus when it copropagates with an intense pump beam under the conditions that the probe and pump beams peak at different positions and propagate in different directions.Due to the effect of cross-phase modulation,the weak beam can not only be focused but also be deflected.The phenomenon is discussed by numerically solving the coupled amplitude equations.

  13. Optically controlled photonic bandgap structures for microstrip circuits

    CERN Document Server

    Cadman, D A

    2003-01-01

    This thesis is concerned with the optical control of microwave photonic bandgap circuits using high resistivity silicon. Photoconducting processes that occur within silicon are investigated. The influence of excess carrier density on carrier mobility and lifetime is examined. In addition, electron-hole pair recombination mechanisms (Shockley-Read-Hall, Auger, radiative and surface) are investigated. The microwave properties of silicon are examined, in particular the variation of silicon reflectivity with excess carrier density. Filtering properties of microstrip photonic bandgap structures and how they may be controlled optically are studied. A proof-of-concept microstrip photonic bandgap structure with optical control is designed, simulated and measured. With no optical illumination incident upon the silicon, the microstrip photonic bandgap structure's filtering properties are well-defined; a 3dB stopband width of 2.6GHz, a 6dB bandwidth of 2GHz and stopband depth of -11.6dB at the centre frequency of 9.9GHz...

  14. Ultrafast defect dynamics: A new approach to all optical broadband switching employing amorphous selenium thin films

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Rituraj; Adarsh, K. V., E-mail: drabold@ohio.edu, E-mail: adarsh@iiserb.ac.in [Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066 (India); Prasai, Kiran; Drabold, D. A., E-mail: drabold@ohio.edu, E-mail: adarsh@iiserb.ac.in [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)

    2015-07-15

    Optical switches offer higher switching speeds than electronics, however, in most cases utilizing the interband transitions of the active medium for switching. As a result, the signal suffers heavy losses. In this article, we demonstrate a simple and yet efficient ultrafast broadband all-optical switching on ps timescale in the sub-bandgap region of the a-Se thin film, where the intrinsic absorption is very weak. The optical switching is attributed to short-lived transient defects that form localized states in the bandgap and possess a large electron-phonon coupling. We model these processes through first principles simulation that are in agreement with the experiments.

  15. Picosecond all-optical switching in hydrogenated amorphous silicon microring resonators

    CERN Document Server

    Pelc, Jason S; Vo, Sonny; Santori, Charles; Fattal, David A; Beausoleil, Raymond G

    2014-01-01

    We utilize cross-phase modulation to observe all-optical switching in microring resonators fabricated with hydrogenated amorphous silicon (a-Si:H). Using 2.7-ps pulses from a mode-locked fiber laser in the telecom C-band, we observe optical switching of a cw telecom-band probe with full-width at half-maximum switching times of 14.8 ps, using approximately 720 fJ of energy deposited in the microring. In comparison with telecom-band optical switching in crystalline silicon microrings, a-Si:H exhibits substantially higher switching speeds due to reduced impact of free-carrier processes.

  16. Ultrafast defect dynamics: A new approach to all optical broadband switching employing amorphous selenium thin films

    Directory of Open Access Journals (Sweden)

    Rituraj Sharma

    2015-07-01

    Full Text Available Optical switches offer higher switching speeds than electronics, however, in most cases utilizing the interband transitions of the active medium for switching. As a result, the signal suffers heavy losses. In this article, we demonstrate a simple and yet efficient ultrafast broadband all-optical switching on ps timescale in the sub-bandgap region of the a-Se thin film, where the intrinsic absorption is very weak. The optical switching is attributed to short-lived transient defects that form localized states in the bandgap and possess a large electron-phonon coupling. We model these processes through first principles simulation that are in agreement with the experiments.

  17. Novel Folding Large-Scale Optical Switch Matrix with Total Internal Reflection Mirrors on Silicon-on-Insulator by Anisotropy Chemical Etching

    Institute of Scientific and Technical Information of China (English)

    LIU Jing-Wei; YU Jin-Zhong; CHEN Shao-Wu

    2005-01-01

    A compact optical switch matrix was designed, in which light circuits were folded by total internal reflective (TIR) mirrors. Two key elements, 2 × 2 switch and TIR mirror, have been fabricated on silicon-on-insulator wafer by anisotropy chemical etching. The 2 × 2 switch showed very low power consumption of 140mW and avery high speed of 8 ± 1 μs. An improved design for the TIR mirror was developed, and the fabricated mirror with smooth and vertical reflective facet showed low excess loss of 0.7 ± 0.3 dB at 1.55μm.

  18. A 10-bit 50-MS/s sample-and-hold circuit with low distortion sampling switches

    Institute of Scientific and Technical Information of China (English)

    Zhu Xubin; Ni Weining; Shi Yin

    2009-01-01

    A fully-differential switched-capacitor sample-and-hold (S/H) circuit used in a 10-bit 50-MS/s pipeline analog-to-digital converter (ADC) was designed and fabricated using a 0.35-μm CMOS process. Capacitor fliparound architecture was used in the S/H circuit to lower the power consumption. In addition, a gain-boosted operational transconductance amplifier (OTA) was designed with a DC gain of 94 dB and a unit gain bandwidth of 460 MHz at a phase margin of 63 degree, which matches the S/H circuit. A novel double-side bootstrapped switch was used, improving the precision of the whole circuit. The measured results have shown that the S/H circuit reaches a spurious free dynamic range (SFDR) of 67 dB and a signal-to-noise ratio (SNR) of 62.1 dB for a 2.5 MHz input signal with 50 MS/s sampling rate. The 0.12 mm2 S/H circuit operates from a 3.3 V supply and consumes 13.6 mW.

  19. A 10-bit 50-MS/s sample-and-hold circuit with low distortion sampling switches

    Science.gov (United States)

    Xubin, Zhu; Weining, Ni; Yin, Shi

    2009-05-01

    A fully-differential switched-capacitor sample-and-hold (S/H) circuit used in a 10-bit 50-MS/s pipeline analog-to-digital converter (ADC) was designed and fabricated using a 0.35-μm CMOS process. Capacitor flip-around architecture was used in the S/H circuit to lower the power consumption. In addition, a gain-boosted operational transconductance amplifier (OTA) was designed with a DC gain of 94 dB and a unit gain bandwidth of 460 MHz at a phase margin of 63 degree, which matches the S/H circuit. A novel double-side bootstrapped switch was used, improving the precision of the whole circuit. The measured results have shown that the S/H circuit reaches a spurious free dynamic range (SFDR) of 67 dB and a signal-to-noise ratio (SNR) of 62.1 dB for a 2.5 MHz input signal with 50 MS/s sampling rate. The 0.12 mm2 S/H circuit operates from a 3.3 V supply and consumes 13.6 mW.

  20. A Novel Mechanism for Contention Resolution in Parallel Optical Burst Switching (POBS) Networks

    OpenAIRE

    Mohammed Joudah Zaiter; Salman Yussof; Abid Abdelouhahab; Cheng Lai Cheah; Adnan brahem Salih

    2014-01-01

    Parallel Optical Burst Switching (POBS) is a variant of Optical Burst Switching (OBS) which is proposed as a new optical switching strategy for Ultra-Dense Wavelength Division Multiplexing (U-DWDM) to support the enormous bandwidth demand of the next generation Internet. As opposed to OBS, POBS transmits bursts in two dimensions: the wavelength dimension and the time dimension. POBS network uses an one-way resource reservation mechanism to set up the resources for each data burst transmission...

  1. Optically controlled multiple switching operations of DNA biopolymer devices

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Chao-You; Tu, Waan-Ting; Lin, Yi-Tzu [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Fruk, Ljiljana [Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA (United Kingdom); Hung, Yu-Chueh, E-mail: ychung@ee.nthu.edu.tw [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2015-12-21

    We present optically tunable operations of deoxyribonucleic acid (DNA) biopolymer devices, where a single high-resistance state, write-once read-many-times memory state, write-read-erase memory state, and single low-resistance state can be achieved by controlling UV irradiation time. The device is a simple sandwich structure with a spin-coated DNA biopolymer layer sandwiched by two electrodes. Upon irradiation, the electrical properties of the device are adjusted owing to a phototriggered synthesis of silver nanoparticles in DNA biopolymer, giving rise to multiple switching scenarios. This technique, distinct from the strategy of doping of pre-formed nanoparticles, enables a post-film fabrication process for achieving optically controlled memory device operations, which provides a more versatile platform to fabricate organic memory and optoelectronic devices.

  2. Optical switching and bistability in four-level atomic systems

    Science.gov (United States)

    Kumar, Pardeep; Dasgupta, Shubhrangshu

    2016-08-01

    We explore the coherent control of nonlinear absorption of intense laser fields in four-level atomic systems. For instance, in a four-level ladder system, a coupling field creates electromagnetically induced transparency (EIT) with an Aulter-Townes doublet for the probe field while the control field is absent. A large absorption peak appears at resonance as the control field is switched on. We show how such a large absorption leads to optical switching. Further, this large absorption diminishes and a transparency window appears due to the saturation effects as the strength of the probe field is increased. We further demonstrate that the threshold of the optical bistability can be modified by suitable choices of the coupling and the control fields. In a four-level Y -type configuration, the effect of the control field on saturable absorption (SA) and reverse saturable absorption (RSA) is highlighted in the context of nonlinear absorption of the probe field. We achieve RSA and SA in a simple atomic system just by applying a control field.

  3. A novel high-speed magneto-optic switch design and analysis

    Science.gov (United States)

    Zhu, Yun; Weng, Zihua; Huang, Yuanqing; Chen, Zhimin

    2006-01-01

    A novel type of 2×2 polarization independent magneto-optic switch with low Insertion Loss, nanosecond order switching time is designed and analyzed. The study of the magneto-optic switch involves two main parts: Faraday rotator assembly and optical route design. In faraday rotator design, magneto-optic crystal comparison and selection, two types of Faraday rotator assembly schemes design and analysis; high speed magnetic field simulation and generation; nanosecond trigger signal generator design, simulation and experiment are involved. Within optical router design, a simple but effective optical router with 2×2 mode is introduced. The nanosecond trigger signal supply to the Faraday rotator assembly is 12ns. The key characteristics, insertion loss, far-end crosstalk, switching time of magneto-optic switch that developed at a wavelength of 1550nm have been tested and root causes analyzed.

  4. Integrated Optical Switching Matrices Constructed from Digital Optical Switches Based on Polymeric Rib Waveguides

    OpenAIRE

    Hauffe, Ralf

    2002-01-01

    Die Arbeit beschäftigt sich mit dem Design und der Realisierung von photonischen Schaltmatrizen für "Optical Cross Connects", die in optisch transparenten Telekommunikationsnetzen benötigt werden, um eine dynamische Umkonfiguration der Netze bei gleichzeitiger Erhaltung von Bitraten-, Wellenlängen- und Protokoll-Transparenz zu ermöglichen. Insbesondere wurden 4x4 Schaltmatrizen basierend auf polymeren Wellenleiterstrukturen untersucht und deren Nebensprechen minimiert. Das Hauptergebnis diese...

  5. Cascaded all-optical operations in a hybrid integrated 80-Gb/s logic circuit.

    Science.gov (United States)

    LeGrange, J D; Dinu, M; Sochor, T; Bollond, P; Kasper, A; Cabot, S; Johnson, G S; Kang, I; Grant, A; Kay, J; Jaques, J

    2014-06-01

    We demonstrate logic functionalities in a high-speed all-optical logic circuit based on differential Mach-Zehnder interferometers with semiconductor optical amplifiers as the nonlinear optical elements. The circuit, implemented by hybrid integration of the semiconductor optical amplifiers on a planar lightwave circuit platform fabricated in silica glass, can be flexibly configured to realize a variety of Boolean logic gates. We present both simulations and experimental demonstrations of cascaded all-optical operations for 80-Gb/s on-off keyed data.

  6. Design and performance of a high speed driver circuit for PIN diode switches used in microwave hyperthermia.

    Science.gov (United States)

    Ryan, T P; Miller, W

    1989-03-01

    In many cancer treatment facilities where hyperthermia treatments are performed, there is a need to split a single channel microwave source into multiple, individually controllable channels. In the application reported here, microwave power is alternately switched between active and passive elements for each channel. The active element is either a microwave antenna inside a catheter in tumour tissue or a planar spiral applicator placed superficially, the total power to each channel being pulse width modulated from 1 to 99% of a 1 s duty cycle. The system is computer controlled and is capable of dividing and controlling power to 12 channels. PIN diode switch assemblies control the flow of power in each channel but they must be switched within a few microseconds to avoid failure at the high power levels used in the clinic. A high speed circuit was fabricated and tested to drive each PIN diode switch; the PIN diode switches are turned on in 1.5 microseconds and off in 3.0 microseconds, which meets the specifications for hot switching. The increase in speed over the former driver system is a factor of 5.1 for the on cycle and 1.5 x 10(5) for the off cycle and the maximum power tested in each channel was 80 W for 1 h at random duty cycles between 1 and 99%. The circuit was also tested with 40 W of power at duty cycles of 1, 50 and 99% for 1 h each; no failures or performance decrements were observed. The 12 channel circuit driver has been used for six months of clinical treatments without failure. PMID:2704213

  7. Local and nonlocal optically induced transparency effects in graphene-silicon hybrid nanophotonic integrated circuits.

    Science.gov (United States)

    Yu, Longhai; Zheng, Jiajiu; Xu, Yang; Dai, Daoxin; He, Sailing

    2014-11-25

    Graphene is well-known as a two-dimensional sheet of carbon atoms arrayed in a honeycomb structure. It has some unique and fascinating properties, which are useful for realizing many optoelectronic devices and applications, including transistors, photodetectors, solar cells, and modulators. To enhance light-graphene interactions and take advantage of its properties, a promising approach is to combine a graphene sheet with optical waveguides, such as silicon nanophotonic wires considered in this paper. Here we report local and nonlocal optically induced transparency (OIT) effects in graphene-silicon hybrid nanophotonic integrated circuits. A low-power, continuous-wave laser is used as the pump light, and the power required for producing the OIT effect is as low as ∼0.1 mW. The corresponding power density is several orders lower than that needed for the previously reported saturated absorption effect in graphene, which implies a mechanism involving light absorption by the silicon and photocarrier transport through the silicon-graphene junction. The present OIT effect enables low power, all-optical, broadband control and sensing, modulation and switching locally and nonlocally. PMID:25372937

  8. All-Optical Routing of Single Photons by a One-Atom Switch Controlled by a Single Photon

    CERN Document Server

    Shomroni, Itay; Lovsky, Yulia; Bechler, Orel; Guendelman, Gabriel; Dayan, Barak

    2014-01-01

    The prospect of quantum networks, in which quantum information is carried by single photons in photonic circuits, has long been the driving force behind the effort to achieve all-optical routing of single photons. Here we realize the most basic unit of such a photonic circuit: a single-photon activated switch, capable of routing a photon from any of its two inputs to any of its two outputs. Our device is based on a single 87Rb atom coupled to a fiber-coupled, chip-based microresonator, and is completely all-optical, requiring no other fields beside the in-fiber single-photon pulses. Nonclassical statistics of the control pulse confirm that a single reflected photon toggles the switch from high reflection (65%) to high transmission (90%), with average of ~1.5 control photons per switching event (~3 including linear losses). The fact that the control and target photons are both in-fiber and practically identical makes this scheme compatible with scalable architectures for quantum information processing.

  9. A balanced, superconducting multiplier circuit for fast-switching and multiplexed qubit readout: Performance and demonstration

    Science.gov (United States)

    Moores, Brad A.; Chapman, Benjamin J.; Rosenthal, Eric I.; Kerckhoff, Joseph; Lehnert, K. W.

    A major challenge of scaling the promising transmon qubits into a quantum information processing machine is the classical hardware burden required to readout many qubits. Within the cavity QED architecture, qubit states are measured by detecting the transmission through microwave cavities. A multiplexing scheme could allow the classical hardware burden of generating and measuring a readout tone to be shared among several cavity-qubit systems. In this talk, we will present measurements of a recently designed superconducting multiplier circuit intended to accomplish time and code domain multiplexed readout. In particular, we characterize three modes of microwave operation: transmission, reflection and inversion. The device can be switched between these modes approximately 100 times faster than typical qubit coherence times. Exploiting this performance, we demonstrate a code domain multiplexing scheme with classical signals created to simulate typical qubit signals. The scheme operates with near unity fidelity at microwave powers comparable to typical qubit tones. This work is supported by the ARO under the Contract W911NF-14-1-0079.

  10. Investigation of DC hybrid circuit breaker based on high-speed switch and arc generator

    Science.gov (United States)

    Wu, Yifei; Rong, Mingzhe; Wu, Yi; Yang, Fei; Li, Mei; Zhong, Jianying; Han, Guohui; Niu, Chunping; Hu, Yang

    2015-02-01

    A new design of DC hybrid circuit breaker based on high-speed switch (HSS) and arc generator (AG), which can drastically profit from low heat loss in normal state and fast current breaking under fault state, is presented and analyzed in this paper. AG is designed according to the magnetic pinch effect of liquid metal. By utilizing the arc voltage generated across AG, the fault current is rapidly commutated from HSS into parallel connected branch. As a consequence, the arcless open of HSS is achieved. The post-arc conducting resume time (Δ tc) of AG and the commutation original voltage (Uc), two key factors in the commutation process, are investigated experimentally. Particularly, influences of the liquid metal channel diameter (Φ) of AG, fault current rate of rise (di/dt) and Uc on Δ tc are focused on. Furthermore, a suitable Uc is determined during the current commutation process, aiming at the reliable arcless open of HSS and short breaking time. Finally, the fault current breaking test is carried out for the current peak value of 11.8 kA, and the validity of the design is confirmed by the experimental results.

  11. Temperature control of molecular circuit switch responsible for virulent phenotype expression in uropathogenic Escherichia coli

    Science.gov (United States)

    Samoilov, Michael

    2010-03-01

    The behavior and fate of biological organisms are to a large extent dictated by their environment, which can be often viewed as a collection of features and constraints governed by physics laws. Since biological systems comprise networks of molecular interactions, one such key physical property is temperature, whose variations directly affect the rates of biochemical reactions involved. For instance, temperature is known to control many gene regulatory circuits responsible for pathogenicity in bacteria. One such example is type 1 fimbriae (T1F) -- the foremost virulence factor in uropathogenic E. coli (UPEC), which accounts for 80-90% of all community-acquired urinary tract infections (UTIs). The expression of T1F is randomly `phase variable', i.e. individual cells switch between virulent/fimbriate and avirulent/afimbriate phenotypes, with rates regulated by temperature. Our computational investigation of this process, which is based on FimB/FimE recombinase-mediated inversion of fimS DNA element, offers new insights into its discrete-stochastic kinetics. In particular, it elucidates the logic of T1F control optimization to the host temperature and contributes further understanding toward the development of novel therapeutic approaches to UPEC-caused UTIs.

  12. Ultrafast Nyquist OTDM demultiplexing using optical Nyquist pulse sampling in an all-optical nonlinear switch.

    Science.gov (United States)

    Hirooka, Toshihiko; Seya, Daiki; Harako, Koudai; Suzuki, Daiki; Nakazawa, Masataka

    2015-08-10

    We propose the ultrahigh-speed demultiplexing of Nyquist OTDM signals using an optical Nyquist pulse as both a signal and a sampling pulse in an all-optical nonlinear switch. The narrow spectral width of the Nyquist pulses means that the spectral overlap between data and control pulses is greatly reduced, and the control pulse itself can be made more tolerant to dispersion and nonlinear distortions inside the nonlinear switch. We apply the Nyquist control pulse to the 640 to 40 Gbaud demultiplexing of DPSK and DQPSK signals using a nonlinear optical loop mirror (NOLM), and demonstrate a large performance improvement compared with conventional Gaussian control pulses. We also show that the optimum spectral profile of the Nyquist control pulse depends on the walk-off property of the NOLM.

  13. Research progresses of SOI optical waveguide devices and integrated optical switch matrix

    Institute of Scientific and Technical Information of China (English)

    YU Jinzhong; CHEN Shaowu; XIA Jinsong; WANG Zhangtao; FAN Zhongchao; LI Yanping; LIU Jingwei; YANG Di; CHEN Yuanyuan

    2005-01-01

    SOI (silicon-on-insulator) is a new material with a lot of important perform- ances such as large index difference, low transmission loss. Fabrication processes for SOI based optoelectronic devices are compatible with conventional IC processes. Having the potential of OEIC monolithic integration, SOI based optoelectronic devices have shown many good characteristics and become more and more attractive recently. In this paper, the recent progresses of SOI waveguide devices in our research group are presented. By highly effective numerical simulation, the single mode conditions for SOI rib waveguides with rectangular and trapezoidal cross-section were accurately investigated. Using both chemical anisotropic wet etching and plasma dry etching techniques, SOI single mode rib waveguide, MMI coupler, VOA (variable optical attenuator), 2×2 thermal-optical switch were successfully designed and fabricated. Based on these, 4×4 and 8×8 SOI optical waveguide integrated switch matrixes are demonstrated for the first time.

  14. All-optical switching characteristics in bacteriorhodopsin and its applications in integrated optics

    Science.gov (United States)

    Huang, Yuhua; Wu, Shin-Tson; Zhao, Youyuan

    2004-03-01

    We experimentally and theoretically investigated the optical switching characteristics of bacteriorhodopsin (bR) at l=633 nm using the pump-probe method. A diode-pumped second harmonic YAG laser (l=532 nm which is located around the maximum initial Br state absorption) was used as a pumping beam and a cw He-Ne laser (l=633 nm which is around the peaks of K and O states) was used as a probe. Due to the nonlinear intensity induced excited state absorption of the K, L, M, N, and O states in the bR photocycle, the switching characteristics are sensitive to the intensity of the probe and pump beams. Based on this property, we have demonstrated an all-optical device functioning as 11 kinds of variable binary all-optical logic gates.

  15. Remote fiber optic switch powered by light for robust interrogation of fiber Bragg grating sensor networks

    International Nuclear Information System (INIS)

    In this work, a remote fiber optic switch powered by light is demonstrated experimentally. This fiber optic switch is powered by a photovoltaic power converter illuminated by a Raman laser. The switch can operate at distances up to 100 km. This switch is used to develop a remote resilient fiber Bragg grating (FBG) multiplexing network interrogated by a commercial FBG interrogator. In the proposed set-up the switch selects the branch of the FBG network located 50 km away from the interrogation unit in order to enable a two-way interrogation path for each sensor to prevent connection failures or fiber breakages. (paper)

  16. Large-scale photonic integrated circuits for long-haul transmission and switching

    Science.gov (United States)

    Nagarajan, Radhakrishnan; Kato, Masaki; Pleumeekers, Jacco; Evans, Peter; Lambert, Damien; Chen, Arnold; Dominic, Vince; Mathur, Atul; Chavarkar, Prashant; Missey, Mark; Dentai, Andrew; Hurtt, Sheila; Bã¤Ck, Johan; Muthiah, Ranjani; Murthy, Sanjeev; Salvatore, Randal; Joyner, Charles; Rossi, Jon; Schneider, Richard; Ziari, Mehrdad; Tsai, Huan-Shang; Bostak, Jeffrey; Kauffman, Michael; Pennypacker, Stephen; Butrie, Timothy; Reffle, Michael; Mehuys, Dave; Mitchell, Matthew; Nilsson, Alan; Grubb, Stephen; Kish, Fred; Welch, David

    2007-02-01

    Dense wavelength division multiplexed (DWDM) large-scale, single-chip transmitter and receiver photonic integrated circuits (PICs), each capable of operating at 100 Gbits/s, have been deployed in the field since the end of 2004. These highly integrated InP chips have significantly changed the economics of long-haul optical transport networks. First, a review of the ten-channel, 100 Gbits/s PIC is presented. Then two extensions of the technology are demonstrated; first is wide temperature, coolerless operation of the 100 Gbits/s PIC, and second is a single integrated chip with 40 channels operating at 40 Gbits/s, capable of an aggregate data rate of 1.6 Tbits/s.

  17. Integrated coherent matter wave circuits

    International Nuclear Information System (INIS)

    An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through their electric polarizability. Moreover, the source of coherent matter waves is a Bose-Einstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry

  18. Optimization of Waveguide Structure for Tunable Optical Switch in Si/SiGe System

    Institute of Scientific and Technical Information of China (English)

    Seongjae; Boo; Won-Taek; Han

    2003-01-01

    A new electro-optical device using Si/SiGe-system with two parallel ridge waveguides is proposed for optical switching and the optimization of the structure for a single mode operation is investigated.

  19. The cascaded amplifier and saturable absorber (CASA) all-optical switch

    DEFF Research Database (Denmark)

    Hilliger, E.; Berger, J.; Weber, H. G.;

    2001-01-01

    The cascaded amplifier and saturable absorber is presented as a new all-optical switching scheme for optical signal processing applications. First demultiplexing experiments demonstrate the principle of operation of this scheme....

  20. MEMS Torsion-Mirror Actuators for Optical Switching or Attenuating Applications

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Novel MEMS torsion-mirror actuators with monolithically integrated fiber self-holding structures are fabricated, and investigated experimentally and theoretically. Their electromechanical and optical characteristics are acceptable for optical switching or attenuating applications.

  1. Monolithic, High-Speed Fiber-Optic Switching Array for Lidar Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This NASA SBIR Phase II effort will develop a 1 x 10 prototype non-mechanical fiber optic switch for use with high power lasers. The proposed optical device is a...

  2. SOI-Based 16×16 Thermo-Optic Waveguide Switch Matrix

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuan-Yuan; LI Yan-Ping; SUN Fei; YANG Di; CHEN Shao-Wu; YU Jin-Zhong

    2006-01-01

    @@ A 16 × 16 thermo-optic waveguide switch matrix has been designed and fabricated on silicon-on-insulator wafer.For reducing device length, blocking switch matrix configuration is chosen. The building block of the matrix is a 2 × 2 switch cell with a Mach-Zehnder interferometer configuration, where a multi-mode interferometer serves as splitter/combiners. Spot size converters and isolating grooves are integrated on the same chip to reduce loss and power consumption. Average power consumption of the switch cell is 220mW. The switching time of a switch cell is less than 3 μs.

  3. High-speed 2×2 silicon-based electro-optic switch with nanosecond switch time

    Institute of Scientific and Technical Information of China (English)

    Xu Xue-Jun; Chen Shao-Wu; Xu Hai-Hua; Sun Yang; Yu Yu-De; Yu Jin-Zhong; Wang Qi-Ming

    2009-01-01

    A 2 × 2 electro-optic switch is experimentally demonstrated using the optical structure of a Mach-Zehnder interferometer (MZI) based on a submicron rib waveguide and the electrical structure of a PIN diode on silicon-on-insulator (SOI). The switch behaviour is achieved through the plasma dispersion effect of silicon. The device has a modulation arm of 1 mm in length and cross-section of 400 nm×340 nm. The measurement results show that the switch has a VπLπ figure of merit of 0.145 V.cm and the extinction ratios of two output ports and cross talk are 40 dB,28 dB and -28 dB,respectively. A 3 dB modulation bandwidth of 90 MHz and a switch time of 6.8 ns for the rise edge and 2.7 ns for the fall edge axe also demonstrated.

  4. Magnetostrictive Micro Mirrors for an Optical Switch Matrix

    Directory of Open Access Journals (Sweden)

    Myeong-Woo Cho

    2007-10-01

    Full Text Available We have developed a wireless-controlled compact optical switch by siliconmicromachining techniques with DC magnetron sputtering. For the optical switchingoperation, micro mirror is designed as cantilever shape size of 5mm×800μm×50μm.TbDyFe film is sputter-deposited on the upper side of the mirror with the condition as: Argas pressure below 1.2×10-9 torr, DC input power of 180W and heating temperature of up to250°C for the wireless control of each component. Mirrors are actuated by externallyapplied magnetic fields for the micro application. Applied beam path can be changedaccording to the direction and the magnitude of applied magnetic field. Reflectivity changes,M-H curves and X-ray diffractions of sputtered mirrors are measured to determine magneto-optical, magneto-elastic properties with variation in sputtered film thickness. The deflectedangle-magnetic field characteristics of the fabricated mirror are measured.

  5. Performance analysis of optical multicast in a new switching structure

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The emergence of new services demands multicast function in optical network.Because of the high cost and complex architecture of multicast capable (MC) node, splitter-sharing switch structure is introduced in which the light splitters are shared by all input signals.To accommodate to this situation, by extending resource ReSerVation protocol-traffic engineering (RSVP-TE) and open shortest path first-traffic engineering (OSPF-TE), a new optical multicast mechanism is provided and the signaling flow and its finite state machine model are given.At the same time, a multicast routing algorithm in splitter-sharing optical network and a changing link weight policy to balance network traffic are proposed.Simulations in NSFNET show no matter with or without wavelength converters, when the number of splitters is 25% of that demanded by traditional MC nodes, the multicast performance has been close to the ideal circumstance.Wavelength converters and changing link weight help much in improving the traffic performance when the number of splitters is adequate.

  6. Cascaded transformerless DC-DC voltage amplifier with optically isolated switching devices

    Science.gov (United States)

    Sridharan, Govind (Inventor)

    1993-01-01

    A very high voltage amplifier is provided in which plural cascaded banks of capacitors are switched by optically isolated control switches so as to be charged in parallel from the preceding stage or capacitor bank and to discharge in series to the succeeding stage or capacitor bank in alternating control cycles. The optically isolated control switches are controlled by a logic controller whose power supply is virtually immune to interference from the very high voltage output of the amplifier by the optical isolation provided by the switches, so that a very high voltage amplification ratio may be attained using many capacitor banks in cascade.

  7. A Novel Model of Resolving Contention in Optical Burst Switched Networks

    Institute of Scientific and Technical Information of China (English)

    Huang Anpeng(黄安鹏); Xie Linzhen; Li Jingcong; Li Zhengbin; Xu Anshi

    2004-01-01

    A Novel segmentation and feedback model (SFM) applied to resolve collision has been proposed. The SFM is featured with Burst Segmentation and Prioritized Feedback (BSPF) that are used to provide quality of service (QoS) and realize high throughput and faster switching in the optical burst switched networks. Simulation and performance analyses show that the SFM effectively avoid collision in optical burst switching (OBS). Long delay time of deflection routing and immature technology of wavelength converter and optical buffer are not employed in the SFM. The SFM not only realizes quick switching but also allows preemption for higher priority bursts.

  8. Demonstration of Optically Controlled re-Routing in a Photonic Crystal Three-Port Switch

    DEFF Research Database (Denmark)

    Combrié, S.; Heuck, Mikkel; Xavier, S.;

    2012-01-01

    We present an experimental demonstration of optically controlled re-routing of a signal in a photonic crystal cavity-waveguide structure with 3 ports. This represents a key functionality of integrated all-optical signal processing circuits....

  9. SIMPLIFIED METHOD FOR CALCULATING CLOSING IN OF SWITCH-GEAR FLEXIBLE BUSES AT SHORT CIRCUIT BY IMPULSE OF ELECTRODYNAMIC FORCES

    OpenAIRE

    I. I. Sergey; E. G. Ponomarenko; W. M. Sammur; P. I. Klimkovich

    2005-01-01

    The paper contains description of a simplified method for calculating closing-in of switch-gear flexible buses at short circuit. The developed method is based on integral and energy principles of  mechanics. In order to increase accuracy of the calculation corrections factors are introduced in an explicit formula for calculation of maximum horizontal deviations. These factors have been obtained with the help of a computer program that realized numerical method for calculating closing-in of wi...

  10. Solving functional reliability issue for an optical electrostatic switch

    CERN Document Server

    Camon, H; Rapahoz, N; Trzmiel, M; Pisella, C; Martínez, C; Gilbert, K; Valette, S

    2008-01-01

    In this paper, we report the advantage of using AC actuating signal for driving MEMS actuators instead of DC voltages. The study is based upon micro mirror devices used in digital mode for optical switching operation. When the pull-in effect is used, charge injection occurs when the micro mirror is maintained in the deflected position. To avoid this effect, a geometrical solution is to realize grounded landing electrodes which are electro-statically separated from the control electrodes. Another solution is the use of AC signal which eliminates charge injection particularly if a bipolar signal is used. Long term experiments have demonstrated the reliability of such a signal command to avoid injection of electric charges.

  11. Ultrafast optical switching of three-dimensional Si inverse opal photonic band gap crystals

    NARCIS (Netherlands)

    Euser, Tijmen G.; Wei, Hong; Kalkman, Jeroen; Jun, Yoonho; Polman, Albert; Norris, David J.; Vos, Willem L.

    2007-01-01

    We present ultrafast optical switching experiments on three-dimensional photonic band gap crystals. Switching the Si inverse opal is achieved by optically exciting free carriers by a two-photon process. We probe reflectivity in the frequency range of second order Bragg diffraction where the photonic

  12. Research of Asymmetric Y-Branching Total Internal Reflection All-Optical Switch

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Y-branching TIR all-optical switch have been fabricated. When the switching optical intensity is 149.9W/mm2, the extinction ratio is 18dB. A theoretical model was also proposed which provided a good fit to the experimental data.

  13. Scalable In-Band Optical Notch-Filter Labeling for Ultrahigh Bit Rate Optical Packet Switching

    DEFF Research Database (Denmark)

    Medhin, Ashenafi Kiros; Galili, Michael; Oxenløwe, Leif Katsuo

    2014-01-01

    We propose a scalable in-band optical notch-filter labeling scheme for optical packet switching of high-bit-rate data packets. A detailed characterization of the notch-filter labeling scheme and its effect on the quality of the data packet is carried out in simulation and verified by experimental...... demonstrations. The scheme is able to generate more than 91 different labels that can be applied to 640-Gb/s optical time division multiplexed packets causing an eye opening penalty of $1.2-dB. Experimental demonstration shows that up to 256 packets can be uniquely labeled by employing up to eight notch filters...... with only 0.9-dB power penalty to achieve BER of 1E-9. Using the proposed labeling scheme, optical packet switching of 640 Gb/s data packets is experimentally demonstrated in which two data packets are labeled by making none and one spectral hole using a notch filter and are switched using a LiNbO$_3...

  14. High-speed switching characteristics of integrated optoelectronic crossbar switch

    Science.gov (United States)

    Gouin, Francois L.; Almeida, Carlos; Callender, Claire L.; Robitaille, Lucie; Noad, Julian P.

    1999-04-01

    Optoelectronic (OE) switching is a promising approach for routing signals in fiber optic networks. Recently, the integration of a 4 X 4 MSM array with optical surface waveguides has been reported. This technique greatly simplifies the packaging of an OE switch. The on-chip polyimide optical waveguides perform the optical signal distribution to a matrix of MSMs which are responsible for the switching operation itself. Photoresponse bandwidths exceeding 4 GHz have been demonstrated. Another important characteristic of a switch is the switching speed since it determines the reconfiguration time. Mechanical and thermal optical waveguide switches offer switching speeds of the order of milliseconds which is sufficient for network traffic management but too slow for packet switching. We report measurements on the switching characteristics of a 4 X 4 optoelectronic switch performed in both the frequency and time domain. In the time domain, the individual crosspoints exhibit a rise time of 3 ns. However, a sizeable overshoot and ringing settles only after 35 ns. This constitutes the reconfiguration time at present. This is confirmed by measurements in the frequency domain of the electrical transmission from control line to output line. The 3-dB switching bandwidth is a few hundred megahertz. The 35 ns reconfiguration time indicates that it is already suitable for packet switching in a 10 Mb/s network. Switching speed measurements on individual MSMs suggests that modifications to the switch circuit could improve the switching time. The switch could also find application as a component in the wavelength conversion circuit of a WDM fiber optic network.

  15. An optimized self-powered switching circuit for non-linear energy harvesting with low voltage output

    International Nuclear Information System (INIS)

    Harvesting energy from environmental sources has been of particular interest these last few years. Microgenerators that can power electronic systems are a solution for the conception of autonomous, wireless devices. They allow the removal of bulky and costly wiring, as well as complex maintenance and environmental issues for battery-powered systems. In particular, using piezoelectric generators for converting vibrational energy to electrical energy is an intensively investigated field. In this domain, it has been shown that the harvested energy can be greatly improved by the use of an original non-linear treatment of the piezoelectric voltage called SSHI (Synchronized Switch Harvesting on Inductor), which consists in intermittently switching the piezoelectric element on a resonant electrical network for a very short time. However, the integration of miniaturized microgenerators with low voltage output (e.g. MEMS microgenerators) has not been widely studied. In the case of low voltage output, the losses introduced by voltage gaps of discrete components such as diodes or transistors can no longer be neglected. Therefore the purpose of this paper is to propose a model that takes into account such losses as well as a new architecture for the SSHI energy harvesting circuit that limits such losses in the harvesting process. While most of the study uses an externally powered microcontroller for the non-linear treatment, this circuit is fully self-powered, thus providing an enhanced autonomous microgenerator. In particular this circuit aims at limiting the effect of non-linear components with a voltage gap such as diodes. It is shown both theoretically and experimentally that the harvested power can be significantly increased using such a circuit. In particular, experimental measurements performed on a cantilever beam show that the circuit allows a 160% increase of the harvested power compared to a standard energy harvesting circuit, while the classical implementation of

  16. Laser Trimming for Adjustment of Grating Offset in Phase-Shifted Fiber Grating Coupler for All-Optical Switching Application

    Institute of Scientific and Technical Information of China (English)

    Hirohisa; Yokota; Yutaka; Sasaki

    2003-01-01

    We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio higher in all-optical FGC switch.

  17. All-optical Data Vortex node using an MZI-SOA switch array

    DEFF Research Database (Denmark)

    Jung, H.D.; Tafur Monroy, Idelfonso; Koonen, A.M.J.;

    2007-01-01

    We propose and demonstrate a new structure of a Data Vortex switch node for all-optical routing of wavelength-division-multiplexing (WDM) 10-Gb/s optical packets. The proposed node consists of two Mach-Zehnder interferometers with integrated semiconductor optical amplifier: an optical AND gate an...

  18. All-optical encryption based on interleaved waveband switching modulation for optical network security.

    Science.gov (United States)

    Fok, Mable P; Prucnal, Paul R

    2009-05-01

    All-optical encryption for optical code-division multiple-access systems with interleaved waveband-switching modulation is experimentally demonstrated. The scheme explores dual-pump four-wave mixing in a 35 cm highly nonlinear bismuth oxide fiber to achieve XOR operation of the plaintext and the encryption key. Bit 0 and bit 1 of the encrypted data are represented by two different wavebands. Unlike on-off keying encryption methods, the encrypted data in this approach has the same intensity for both bit 0 and bit 1. Thus no plaintext or ciphertext signatures are observed.

  19. Plasmon-induced optical switching of electrical conductivity in porous anodic aluminum oxide films encapsulated with silver nanoparticle arrays.

    Science.gov (United States)

    Huang, Chen-Han; Lin, Hsing-Ying; Lau, Ben-Chao; Liu, Chih-Yi; Chui, Hsiang-Chen; Tzeng, Yonhua

    2010-12-20

    We report on plasmon induced optical switching of electrical conductivity in two-dimensional (2D) arrays of silver (Ag) nanoparticles encapsulated inside nanochannels of porous anodic aluminum oxide (AAO) films. The reversible switching of photoconductivity greatly enhanced by an array of closely spaced Ag nanoparticles which are isolated from each other and from the ambient by thin aluminum oxide barrier layers are attributed to the improved electron transport due to the localized surface plasmon resonance and coupling among Ag nanoparticles. The photoconductivity is proportional to the power, and strongly dependent on the wavelength of light illumination. With Ag nanoparticles being isolated from the ambient environments by a thin layer of aluminum oxide barrier layer of controlled thickness in nanometers to tens of nanometers, deterioration of silver nanoparticles caused by environments is minimized. The electrochemically fabricated nanostructured Ag/AAO is inexpensive and promising for applications to integrated plasmonic circuits and sensors. PMID:21197062

  20. Voltage-controllable wavelength-selective optical switching based on multiply cascaded long-period fiber gratings

    Science.gov (United States)

    Han, Young-Geun; Choi, Sun-Min; Kim, Sang Hyuck; Lee, Sang Bae

    2003-11-01

    A novel wavelength-selective optical switching device based on multiply cascaded long-period fiber gratings is proposed and experimentally demonstrated. The on and off states of each channel in the optical switching device can be effectively switched by voltage-controllable coil heaters. The device has advantages of multichannel operation, multiwavelength selectivity, and bandwidth controllability. It can be useful for applications in multiwavelength operational signal gating, optical switching devices, routers, and multiplexers in optical communication systems.

  1. Assessment and modelling of switching technologies for application in HVDC-circuit breakers

    OpenAIRE

    Lund, Johan

    2011-01-01

    A key element for future DC-grids is a DC circuit breaker that in case of a short circuit fault reliably can turn off a short circuit current. AC circuit breakers are well known components that has been in use for a long time in AC-grids. The AC circuit breaker is designed to interrupt the current at its natural current zero crossings. In DC grids such does not exists, therefore AC breakers can not be directly applied in DC grids. Different concepts and technologies to solve this problem is a...

  2. All-Optical Switching in Bacteriorhodopsin Based on Excited-State Absorption

    Science.gov (United States)

    Roy, Sukhdev

    2008-03-01

    Switching light with light is of tremendous importance for both fundamental and applied science. The advent of nano-bio-photonics has led to the design, synthesis and characterization of novel biomolecules that exhibit an efficient nonlinear optical response, which can be utilized for designing all-optical biomolecular switches. Bacteriorhodopsin (bR) protein found in the purple membrane of Halobacterium halobium has been the focus of intense research due to its unique properties that can also be tailored by physical, chemical and genetic engineering techniques to suit desired applications. The talk would focus on our recent results on all-optical switching in bR and its mutants, based on excited-state absorption, using the pump-probe technique. We would discuss the all-optical control of various features of the switching characteristics such as switching contrast, switching time, switching pump intensity, switched probe profile and phase, and relative phase-shift. Optimized conditions for all-optical switching that include optimized values of the small-signal absorption coefficient (for cw case), the pump pulse width and concentration for maximum switching contrast (for pulsed case), would be presented. We would discuss the desired optimal spectral and kinetic properties for device applications. We would also discuss the application of all-optical switching to design low power all-optical computing devices, such as, spatial light modulators, logic gates and multiplexers and compare their performance with other natural photoreceptors such as pharaonis phoborhodopsin, proteorhodopsin, photoactive yellow protein and the blue light plant photoreceptor phototropin.

  3. Wavelength assignment in optical burst switching networks using neuro-dynamic programming

    OpenAIRE

    Keçeli, Feyza

    2003-01-01

    Cataloged from PDF version of article. All-optical networks are the most promising architecture for building large-size, hugebandwidth transport networks that are required for carrying the exponentially increasing Internet traffic. Among the existing switching paradigms in the literature, the optical burst switching is intended to leverage the attractive properties of optical communications, and at the same time, take into account its limitations. One of the major problems in o...

  4. Performance and cost analysis of all-optical switching: OBS and OCS

    Directory of Open Access Journals (Sweden)

    Ekularn Dhavarudha

    2011-08-01

    Full Text Available This paper presents a study of performance and cost analysis of optical circuit switching (OCS and optical burstswitching (OBS by proposing the clear images of their node architectures and cost formulations. Then, we apply servicelevel agreement (SLA of the high quality of service application in the terms of network blocking probability and averagenetwork delay to demonstrate OCS and OBS performances, their investment costs, and network dimensioning methodology.Applying SLA to our studies can illustrate the impact of contention resolution and blocking resolution schemes to theperformances and costs of OBS and OCS, accordingly. The simulations illustrate that OBS applying WC gives the bestperformance among all architectures deploying the same offered bandwidth. The investigations also show that WC is a majortechnique contributing high performance gain to both OCS and OBS. Especially for OBS, WC is an important scheme allowingOBS high data grooming property as its performance gain contributing to OBS is much higher than those of OCS. For thecost analysis, OCS is the most economic among all architectures. BA provides the most cost effectiveness among all OBScontention resolution schemes. Lastly, FDL is the least cost effective scheme as it gives little performance enhancement butadds more cost to the network.

  5. Subcortical volume analysis in traumatic brain injury: the importance of the fronto-striato-thalamic circuit in task switching.

    Science.gov (United States)

    Leunissen, Inge; Coxon, James P; Caeyenberghs, Karen; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

    2014-02-01

    Traumatic brain injury (TBI) is associated with neuronal loss, diffuse axonal injury and executive dysfunction. Whereas executive dysfunction has traditionally been associated with prefrontal lesions, ample evidence suggests that those functions requiring behavioral flexibility critically depend on the interaction between frontal cortex, basal ganglia and thalamus. To test whether structural integrity of this fronto-striato-thalamic circuit can account for executive impairments in TBI we automatically segmented the thalamus, putamen and caudate of 25 patients and 21 healthy controls and obtained diffusion weighted images. We assessed components of executive function using the local-global task, which requires inhibition, updating and switching between actions. Shape analysis revealed localized atrophy of the limbic, executive and rostral-motor zones of the basal ganglia, whereas atrophy of the thalami was more global in TBI. This subcortical atrophy was related to white matter microstructural organization in TBI, suggesting that axonal injuries possibly contribute to subcortical volume loss. Global volume of the nuclei showed no clear relationship with task performance. However, the shape analysis revealed that participants with smaller volume of those subregions that have connections with the prefrontal cortex and rostral motor areas showed higher switch costs and mixing costs, and made more errors while switching. These results support the idea that flexible cognitive control over action depends on interactions within the fronto-striato-thalamic circuit.

  6. New Remote Gas Sensor Using Rapid Electro-Optical Path Switching

    Science.gov (United States)

    Sachse, G. W.; Lebel, P. J.; Wallio, H. A.; Vay, S. A.; Wang, L. G.

    1994-01-01

    Innovative gas filter correlation radiometer (GFCR) features nonmechanical switching of internal optical paths. Incoming radiation switched electro-optically, by means of polarization, between two optical paths, one of which contains correlation gas cell while other does not. Advantages include switching speed, 2 to 3 orders of magnitude faster than mechanical techniques, and high reliability. Applications include regional studies of atmospheric chemistry from either manned or unmanned aircraft as well as satellite studies of global distributions, sources and sink mechanisms for key species involved in chemistry of troposphere. Commercial applications: ability to survey many miles of natural gas pipelines rapidly from aircraft, pinpointing gas leaks by measuring methane at 2.3 micrometers.

  7. Improved optical packet switching structure with recirculation buffer and feedback tunable wavelength converter

    Institute of Scientific and Technical Information of China (English)

    Cheng Wu; Shilin Xiao

    2009-01-01

    The performance of an optical switching network is mainly determined by its core node structure.An improved optical packet switching(OPS)node structure based on recirculation optical fiber delay line(FDL)and feedback tunable wavelength converter(TWC),and a specific scheduling algorithm for the node structure are presented.This switching structure supports both point-to-point and point-to-multi-points broadcasting transmission with superior capacity expansion performance.Its superiority in packet loss probability is proved by simulation.

  8. Photoinduced Birefringence and Broadband All-Optical Photonic Switch in a Bacteriorhodopsin/Polymer Composite Film

    Institute of Scientific and Technical Information of China (English)

    WEI Lai; TENG Xue-Lei; Lu Ming; ZHAO You-Yuan; MA De-Wang; DING Jian-Dong

    2007-01-01

    Photoinduced birefringence with large optical nonlinearity in a bacteriorhodopsin/polymer composite film is observed.A high refractive index change of 8.5×10-5 photoinduced by 476nm pumping beam is reached at the low intensity of 6.5mW/cm2.Based on it,a broadband all-optical photonic switch is realized with an optical controlling switch system.Because of controlling beam's selectivity in switching,the transporting beams of different wavelengths with different intensities and shapes can be modulated by adjusting the wavelength and intensity of the controlling beam.

  9. Digital switching in a biosensor circuit via programmable timing of gene availability

    OpenAIRE

    Lapique, Nicolas; Benenson, Yaakov

    2014-01-01

    Transient delivery of gene circuits is required in many potential applications of synthetic biology, yet pre-steady-state processes that dominate this delivery route pose significant challenges for robust circuit deployment. Here we show that site-specific recombinases can rectify undesired effects by programmable timing of gene availability in multi-gene circuits. We exemplify the concept with a proportional sensor for endogenous microRNA and show dramatic reduction in its ground state leaka...

  10. Numerical investigation of high-contrast ultrafast all-optical switching in low-refractive-index polymeric photonic crystal nanobeam microcavities

    Science.gov (United States)

    Meng, Zi-Ming; Zhong, Xiao-Lan; Wang, Chen; Li, Zhi-Yuan

    2012-06-01

    With the development of micro- or nano-fabrication technologies, great interest has been aroused in exploiting photonic crystal nanobeam structures. In this article the design of high-quality-factor (Q) polymeric photonic crystal nanobeam microcavities suitable for realizing ultrafast all-optical switching is presented based on the three-dimensional finite-difference time-domain method. Adopting the pump-probe technique, the ultrafast dynamic response of the all-optical switching in a nanobeam microcavity with a quality factor of 1000 and modal volume of 1.22 (λ/n)3 is numerically studied and a switching time as fast as 3.6 picoseconds is obtained. Our results indicate the great promise of applying photonic crystal nanobeam microcavities to construct integrated ultrafast tunable photonic devices or circuits incorporating polymer materials with large Kerr nonlinearity and ultrafast response speed.

  11. Transient reconfigurable subangstrom-precise photonic circuits at the optical fiber surface

    CERN Document Server

    Dmitriev, A; Sumetsky, M

    2015-01-01

    Transient fully reconfigurable photonic circuits can be introduced at the optical fiber surface with subangstrom precision. A building block of these circuits, a 0.7 angstrom-precise nano-bottle resonator, is experimentally created by local heating, translated, and annihilated.

  12. Optically-Switched Resonant Tunneling Diodes for Space-Based Optical Communication Applications

    Science.gov (United States)

    Moise, T. S.; Kao, Y. -C.; Jovanovic, D.; Sotirelis, P.

    1995-01-01

    We are developing a new type of digital photo-receiver that has the potential to perform high speed optical-to-electronic conversion with a factor of 10 reduction in component count and power dissipation. In this paper, we describe the room-temperature photo-induced switching of this InP-based device which consists of an InGaAs/AlAs resonant tunneling diode integrated with an InGaAs absorber layer. When illuminated at an irradiance of greater than 5 Wcm(exp -2) using 1.3 micromillimeter radiation, the resonant tunneling diode switches from a high-conductance to a low-conductance electrical state and exhibits a voltage swing of up to 800 mV.

  13. Analysis on optical bistability parameters in photonic switching devices

    Science.gov (United States)

    Sarafraz, Hossein; Sayeh, Mohammad R.

    2016-06-01

    An investigation has been done on the parameters of a hysteretic bistable optical Schmitt trigger device. From a design point of view, it is important to know the regions where this bistability occurs and is fully functional with respect to its subsystem parameters. Otherwise experimentally reaching such behavior will be very time-consuming and frustrating, especially with multiple devices employed in a single photonic circuit. A photonic Schmitt trigger consisting of two feedbacked inverting amplifiers, each characterized by -m (slope), A (y-intercept), and B (constant base) parameters is considered. This system is investigated dynamically with a varying input to find its stable and unstable states both mathematically and with simulation. In addition to a complete mathematical analysis of the system, we also describe how m, A, and B can be properly chosen in order to satisfy certain system conditions that result in bistability. More restrictions are also imposed to these absolute conditions by the system conditions as will be discussed. Finally, all results are verified in a more realistic photonic simulation.

  14. Two types of all-optical magnetization switching mechanisms using femtosecond laser pulses

    Science.gov (United States)

    El Hadri, M. S.; Pirro, P.; Lambert, C.-H.; Petit-Watelot, S.; Quessab, Y.; Hehn, M.; Montaigne, F.; Malinowski, G.; Mangin, S.

    2016-08-01

    Using a time-dependent electrical investigation of the all-optical switching in ferrimagnetic and ferromagnetic Hall crosses via the anomalous Hall effect, intriguing insights into the rich physics underlying the all-optical switching are provided. We demonstrate that two different all-optical magnetization switching mechanisms can be distinguished; a "single pulse" switching for ferrimagnetic GdFeCo alloys, and a "two regimes" switching process for both ferrimagnetic TbCo alloys and ferromagnetic Pt/Co multilayers. We show that the latter takes place at two different time scales, and consists of a steplike helicity-independent multiple-domain formation within the first 1 ms followed by a helicity-dependent remagnetization on several tens of milliseconds.

  15. Design and Implement of the Packet-Circuit Switching Router on Chip%"包-电路交换"片上路由器设计与实现

    Institute of Scientific and Technical Information of China (English)

    万健; 李丽; 王佳文; 张宇昂

    2011-01-01

    As to NoC design, router on chip is very important because it directly impacts the performance of the whole NoC system. Considering the advantages and disadvantages of packet switching and circuit switching, this paper proposes a router on chip based on packet-circuit switching, which has low resource consumption and high- performance, namely packet-circuit switching router.%在片上网络(NoC)设计中,片上路由器的优劣将直接影响整个NoC系统的性能.文中综合考虑了包交换方式和电路交换方式的优缺点,采用"包-电路交换"方式,设计并实现了一种低硬件资源消耗、高性能的"包-电路交换"片上路由器.

  16. Electronic Transport Properties of a Naphthopyran-Based Optical Molecular Switch:an ab initio Study

    Institute of Scientific and Technical Information of China (English)

    XIA Cai-Juan; LIU De-Sheng; ZHANG Ying-Tang

    2011-01-01

    The electronic transport properties of a. Naphthopyran-based molecular optical switch are investigated by using the nonequilibrium Green's Function formalism combined with first-principles density functional theory. The molecule that comprises the switch can convert between its open and closed forms upon photoexcitation. Theoretical results show that the current through the open form is significantly larger than that through the closed form, which is different from other optical switches based on ring-opening reactions of the molecular bridge. The maximum on-off ratio (about 90) can be obtained at 1.4 V. The physical origin of the switching behavior is interpreted based on the spatial distributions of molecular orbitals and the HOMO-LUMO gap. Our result shows that the naphthopyran-based molecule is a good candidate for optical molecular switches and will be useful in the near future.%@@ ronic transport properties of a naphthopyran-based molecular optical switch are investigated by using the nonequilibrium Green's function formalism combined with first-principles density functional theory.The molecule that comprises the switch can convert between its open and closed forms upon photoexcitation.Theoretical results show that the current through the open form is significantly larger than that through the closed form,which is different from other optical switches based on ring-opening reactions of the molecular bridge.The maximum on-off ratio(about 90)can be obtained at 1.4 V.The physical origin of the switching behavior is interpreted based on the spatial distributions of molecular orbitals and the HOMO-LUMO gap.Our result shows that the naphthopyran-based molecule is a good candidate for optical molecular switches and will be useful in the near future.

  17. 640 Gbit/s Optical Packet Switching using a Novel In-Band Optical Notch-Filter Labeling Scheme

    DEFF Research Database (Denmark)

    Medhin, Ashenafi Kiros; Galili, Michael; Oxenløwe, Leif Katsuo

    2014-01-01

    Optical packet switching of 640 Gbit/s data packets is reported using an in-band optical labeling technique based on notch-filtering of the data spectrum and extracting the label using a bandpass filter. BER 10􀀀9 is achieved.......Optical packet switching of 640 Gbit/s data packets is reported using an in-band optical labeling technique based on notch-filtering of the data spectrum and extracting the label using a bandpass filter. BER 10􀀀9 is achieved....

  18. All-optical switching and all-optical logic gates based on bacteriorhodopsin

    Science.gov (United States)

    Huang, Yuhua; Wu, Shin-Tson; Zhao, Youyuan

    2004-06-01

    We demonstrate an all-optical switching using a bacteriorhodopsin (bR) film. The transmission of the bR film is investigated using the pump-probe method. A diode-pumped second harmonic YAG laser (λ = 532nm which is around the maximum initial B state absorption) was used as a pumping beam and a cw He-Ne laser (λ = 632 nm which is around the peaks of K and O states) was used as a probe. Due to the nonlinear intensity induced excited state absorption of the K, L, M, N, and O states in the bR photocycle, the switching characteristics are sensitive to the intensity of the probe and pump beams. Based on this property, we design an all-optical operating device functioning as 11 kinds of variable binary all-optical logic gates. The incident 532nm beam acts as an input to the logic gate and the transmission of the 632nm bears the output of the gate.

  19. All-Optical Switching Using Fabry-Perot Laser Diodes(Invited paper)

    Institute of Scientific and Technical Information of China (English)

    P. K. A. Wai; L. Y. Chan; H. Y. Tam

    2003-01-01

    In this paper, we investigate all-optical packet switching using a multi-wavelength mutual injection-locked Fabry-Perot laser diode. We observe error-free packet-switching of a 10 Gb/s signal with an extinction ratio of 16.9.

  20. Synchronization in a Random Length Ring Network for SDN-Controlled Optical TDM Switching

    DEFF Research Database (Denmark)

    Kamchevska, Valerija; Cristofori, Valentina; Da Ros, Francesco;

    2016-01-01

    . In addition, we propose a novel synchronization algorithm that enables automatic synchronization of software defined networking controlled all-optical TDM switching nodes connected in a ring network. Besides providing synchronization, the algorithm also can facilitate dynamic slot size change and failure...... multiplexing transmission and switching of data bursts when using the proposed algorithm to provide synchronization....

  1. All-Optical Switching Using Fabry-Perot Laser Diodes (Invited paper)

    Institute of Scientific and Technical Information of China (English)

    P.; K.; A.; Wai; L.; Y.; Chan; H.; Y.; Tam

    2003-01-01

    In this paper, we investigate all-optical packet switching using a multi-wavelength mutual injection-locked Fabry-Perot laser diode. We observe error-free packet-switching of a 10 Gb/s signal with an extinction ratio of 16.9.

  2. Porous silicon-VO{sub 2} based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Antunez, E. E.; Salazar-Kuri, U.; Estevez, J. O.; Basurto, M. A.; Agarwal, V., E-mail: vagarwal@uaem.mx [Centro de Investigación en Ingeniería y Ciencias Aplicadas, Instituto de Investigación en Ciencias Básicas y Aplicadas, UAEM, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Mor. 62209 (Mexico); Campos, J. [Instituto de Energías Renovables, UNAM, Priv. Xochicalco S/N, Temixco, Mor. 62580 (Mexico); Jiménez Sandoval, S. [Laboratorio de Investigación en Materiales, Centro de Investigación y estudios Avanzados del Instituto Politécnico Nacional, Unidad Querétaro, Qro. 76001 (Mexico)

    2015-10-07

    Morphological properties of thermochromic VO{sub 2}—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO{sub 2} as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO{sub 2}(M) to a high-temperature tetragonal rutile VO{sub 2}(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO{sub 2} film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology.

  3. Porous silicon-VO2 based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range

    Science.gov (United States)

    Antunez, E. E.; Salazar-Kuri, U.; Estevez, J. O.; Campos, J.; Basurto, M. A.; Jiménez Sandoval, S.; Agarwal, V.

    2015-10-01

    Morphological properties of thermochromic VO2—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO2 as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO2(M) to a high-temperature tetragonal rutile VO2(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO2 film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology.

  4. Porous silicon-VO2 based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range

    International Nuclear Information System (INIS)

    Morphological properties of thermochromic VO2—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO2 as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO2(M) to a high-temperature tetragonal rutile VO2(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO2 film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology

  5. Optical generation and wireless transmission of 60 GHz OOK signals using gain switched laser

    OpenAIRE

    Shams, Haymen; Anandarajah, Prince M.; Perry, Philip; Liam P. Barry

    2010-01-01

    We present a novel, simple and cost effective system for optical millimeter-wave generation and transmission of 3 Gbps data based on gain switching. System performance has been investigated, including wireless transmission and power budget analysis.

  6. 40 Gbit/s NRZ Packet-Length Insensitive Header Extraction for Optical Label Switching Networks

    DEFF Research Database (Denmark)

    Seoane, Jorge; Kehayas, E; Avramopoulos, H.;

    2006-01-01

    A simple method for 40 Gbit/s NRZ header extraction based on envelope detection for optical label switching networks is presented. The scheme is insensitive to packet length and spacing and can be single-chip integrated cost-effectively......A simple method for 40 Gbit/s NRZ header extraction based on envelope detection for optical label switching networks is presented. The scheme is insensitive to packet length and spacing and can be single-chip integrated cost-effectively...

  7. Efficient high repetition rate electro-optic Q-switched laser with an optically active langasite crystal

    Science.gov (United States)

    Ma, Shihui; Yu, Haohai; Zhang, Huaijin; Han, Xuekun; Lu, Qingming; Ma, Changqin; Boughton, Robert I.; Wang, Jiyang

    2016-07-01

    With an optically active langasite (LGS) crystal as the electro-optic Q-switch, we demonstrate an efficient Q-switched laser with a repetition rate of 200 kHz. Based on the theoretical analysis of the interaction between optical activity and electro-optic property, the optical activity of the crystal has no influence on the birefringence during Q-switching if the quarter wave plate used was rotated to align with the polarization direction. With a Nd:LuVO4 crystal possessing a large emission cross-section and a short fluorescence lifetime as the gain medium, a stable LGS Q-switched laser was designed with average output power of 4.39 W, corresponding to a slope efficiency of 29.4% and with a minimum pulse width of 5.1 ns. This work represents the highest repetition rate achieved so far in a LGS Q-switched laser and it can provide a practical Q-switched laser with a tunable high repetition rates for many applications, such as materials processing, laser ranging, medicine, military applications, biomacromolecule materials, remote sensing, etc.

  8. A 4 × 4 Strictly Nonblocking Silicon-on-Insulator Thermo-Optic Switch Matrix

    Institute of Scientific and Technical Information of China (English)

    YANG Di; LI Yan-Ping; CHEN Shao-Wu; YU Jin-Zhong

    2005-01-01

    @@ A 4 × 4 strictly nonblocking thermo-optic switch matrix implemented with a 2 × 2 Mach-Zehnder switch unit was fabricated in silicon-on-insulator wafer. Insertion losses of the shortest and the longest path in the device are about 14.8dB and 19.2dB, respectively. The device presents a very low loss dependent on wavelength. For one switch unit, the power consumption needed for operation is measured to be 0.270 W-0.288 W and the switching time is about 13 ± 1μs.

  9. Fabrication of Thermo-Optic Switch in Silicon-on-Insulator

    Institute of Scientific and Technical Information of China (English)

    王章涛; 夏金松; 樊中朝; 陈少武; 余金中

    2003-01-01

    Silicon-on-insulator technology has been used to fabricate 2 × 2 thermo-optic switches. The switch shows crosstalk of-23.4 dB and extinction ratio of 18.1 dB in the bar-state. The switching speed is less than 30 μs and the power consumption is about 420mW. The measured excess loss is 1.8 dB. These merits make the switch more attractive for applications in wavelength division multiplexing.

  10. Single-photon all-optical switching using coupled microring resonators

    Indian Academy of Sciences (India)

    Wenge Yang; Amitabh Joshi; Min Xiao

    2007-08-01

    We study the nonlinear phase response of a microring resonator coupled to a bus waveguide and the use of this nonlinear phase shift to store information in the microring resonator and enhance the switching characteristics of a Mach–Zehnder interferometer (MZI). By introducing coupling between adjacent microring resonators, the switching characteristics of the MZI can be exponentially enhanced as a function of the number of microring resonators, when compared to the linear enhancement for uncoupled resonators. With only a few moderate-finesse microring resonators, the switching power can be reduced to attowatt level, allowing for photonic switching devices that operate at single-photon level in ordinary optical waveguides.

  11. A novel offset cancellation based on parasitic-insensitive switched-capacitor sensing circuit for the out-of-plane single-Gimbaled decoupled CMOS-MEMS gyroscope.

    Science.gov (United States)

    Chang, Ming-Hui; Huang, Han-Pang

    2013-01-01

    This paper presents a novel parasitic-insensitive switched-capacitor (PISC) sensing circuit design in order to obtain high sensitivity and ultra linearity and reduce the parasitic effect for the out-of-plane single-gimbaled decoupled CMOS-MEMS gyroscope (SGDG). According to the simulation results, the proposed PISC circuit has better sensitivity and high linearity in a wide dynamic range. Experimental results also show a better performance. In addition, the PISC circuit can use signal processing to cancel the offset and noise. Thus, this circuit is very suitable for gyroscope measurement.

  12. Ultrafast coherent dynamics of a photonic crystal all-optical switch

    CERN Document Server

    Colman, Pierre; Yu, Yi; Mørk, Jesper

    2016-01-01

    We present pump-probe measurements of an all-optical photonic crystal switch based on a nanocavity, resolving fast coherent temporal dynamics. The measurements demonstrate the importance of coherent effects typically neglected when considering nanocavity dynamics. In particular, we report the observation of an idler pulse. The measurements are in good agreement with a theoretical model that allows us to ascribe the observation to oscillations of the free carrier population in the nanocavity. The effect opens perspectives for the realization of new all-optical photonic crystal switches with unprecedented switching contrast.

  13. Nanoresonator Enabled Ultrafast All-optical Terahertz Switching Based on Vanadium Dioxide Thin Film

    Science.gov (United States)

    Kyoung, J. S.; Choi, S. B.; Kim, H. S.; Kim, B. J.; Ahn, Y. H.; Kim, H. T.; Kim, D. S.

    2011-12-01

    We demonstrate nanoresonator enabled ultrafast all-optical switching of terahertz transmission based on phase transition of vanadium dioxide (VO2) thin film. Nanoresonators, nm-width slot antenna patterns on the gold layer, are fabricated on the VO2 films. Without nanoresonators, THz wave shows negligible change through bare VO2 film even though optical pumping exists, while about 20 percents switching ratio is clearly seen with nanoresonator patterns on the VO2. The switching time is in a few hundreds femtosecond time scales.

  14. Performance improvements of MOEMS-based diffractive arrays: address isolation and optical switching

    Science.gov (United States)

    Panaman, Ganesh; Madison, Seth; Sano, Michael; Castracane, James

    2005-01-01

    Micro-Opto-Electro-Mechanical Systems (MOEMS) have found a variety of applications in fields such as telecommunications, spectroscopy and display technology. MOEMS-based optical switching is currently under investigation for the increased flexibility that such devices provide for reconfiguration of the I/O network for inter-chip communication applications. This potential not only adds an additional degree of freedom for adjustment of transmitter/receiver links but also allows for fine alignment of individual channels in the network link. Further, this use of diffractive arrays for specific applications combines beam steering/adjustment capabilities with the inherent wavelength dependence of the diffractive approach for channel separation and de-multiplexing. Research and development has been concentrated on the progression from single MOEMS components to parallel arrays integrated with optical source arrays for a successful feasibility demonstration. Successful development of such an approach will have a major impact of the next generation communication protocols. This paper will focus on the current status of the MOEMS research program for Free Space Optical inter-chip communication at the College of NanoScale Science and Engineering, University at Albany-SUNY (CNSE). New versions of diffractive arrays stemming from the basic MEMS Compound Grating (MCG; patent #5,999,319) have been produced through various fabrication methods including the MUMPs process1. Most MEMS components relying on electrostatic actuation tend to require high actuation voltages (>20V) compared to the typical 5V levels prevalent in conventional integrated circuits. The specific goal is to yield improved performance while minimizing the power consumption of the components. Structural modifications through the variation in the ruling/electrode spacing distance and array wiring layout through individually addressable gratings have been studied to understand effects on the actuation voltage and

  15. Equivalent Circuit for Cavity Discharges Including Controlled Current Source and Controlled Switch

    Institute of Scientific and Technical Information of China (English)

    CHEN Weigen; CHEN Xi; XIE Bo; LIU Jun

    2013-01-01

    Numerous equivalent circuits for cavity discharges have been developed,yet most of these models cannot provide simulated signals that precisely reveal the variability of the discharge's characteristic parameters,such as repetition rate,magnitude and phase of discharges,which makes them not suitable for intensive studies of discharge process.Therefore,using Simulink code,we theoretically analyzed and studied the classical equivalent circuits of cavity discharges,as well as the influence of circuit components on simulation results,and then proposed a novel equivalent circuit,the key parameters of which were determined according to the physical behavior of cavity discharges.In the novel equivalent circuit,the repetition rate can be changed by discharge resistance,inception and residual voltages;meanwhile the phase of discharge can be controlled by adjusting the parameters of shunt resistance.Furthermore,a controlled current source as a function of space charge is introduced in the equivalent circuit.Compared with the former ones,the simulated signals obtained by this novel model are better approximation of real signals.This work could be referred by latter studies of the characteristics and the mechanisms of cavity discharge in oil-paper insulation.

  16. Laser cooling and optical detection of excitations in a LC electrical circuit

    DEFF Research Database (Denmark)

    Taylor, J. M.; Sørensen, Anders Søndberg; Marcus, Charles Masamed;

    2011-01-01

    We explore a method for laser cooling and optical detection of excitations in a room temperature LC electrical circuit. Our approach uses a nanomechanical oscillator as a transducer between optical and electronic excitations. An experimentally feasible system with the oscillator capacitively...

  17. Experimental study of electro-optical Q-switched pulsed Nd:YAG laser

    Science.gov (United States)

    A, Maleki; M Kavosh, Tehrani; H, Saghafifar; M, H. Moghtader Dindarlu

    2016-03-01

    We report the specification of a compact and stable side diode-pumped Q-switched pulsed Nd:YAG laser. We experimentally study and compare the performance of the pulsed Nd:YAG laser in the free-running and Q-switched modes at different pulse repetition rates from 1 Hz to 100 Hz. The laser output energy is stabilized by using a special configuration of the optical resonator. In this laser, an unsymmetrical concave-concave resonator is used and this structure helps the mode volume to be nearly fixed when the pulse repetition rate is increased. According to the experimental results in the Q-switched operation, the laser output energy is nearly constant around 70 mJ with an FWHM pulse width of 7 ns at 100 Hz. The optical-to-optical conversion efficiency in the Q-switched regime is 17.5%.

  18. Temperature monitoring and leak detection in sodium circuits of FBR using Raman distributed fiber optic sensor

    International Nuclear Information System (INIS)

    This paper discusses the fiber optic temperature sensor based leak detection in the coolant circuits of fast breeder reactor. These sensors measure the temperature based on spontaneous Raman scattering principle and is not influenced by the electromagnetic interference. Various experiments were conducted to evaluate the performance of the fiber optic sensor based leak detection using Raman distributed Temperature Sensor (RDTS). This paper also deals with the details of fiber optic sensor type leak detector layout for the coolant circuit of FBR, performance requirement of leak detection system, description of the test facility, experimental procedure and test results of various experiments conducted. (author)

  19. Analysis of S-SEED's characteristics in optical switch

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This article introduces the basic structure of a symmetric self-electrooptic effect device (S-SEED), and applies the Kirchoff's current law and a purely equivalent capacitive model, to analyze S-SEED's switch characteristics. Linear approximation and N-segment approximation are utilized to obtain S-SEED's voltage-time (V-T) and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED's switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED's switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED's switch characteristics.

  20. Emerging roles of microRNAs as molecular switches in the integrated circuit of the cancer cell

    Science.gov (United States)

    Sotiropoulou, Georgia; Pampalakis, Georgios; Lianidou, Evi; Mourelatos, Zissimos

    2009-01-01

    Transformation of normal cells into malignant tumors requires the acquisition of six hallmark traits, e.g., self-sufficiency in growth signals, insensitivity to antigrowth signals and self-renewal, evasion of apoptosis, limitless replication potential, angiogenesis, invasion, and metastasis, which are common to all cancers (Hanahan and Weinberg 2000). These new cellular traits evolve from defects in major regulatory microcircuits that are fundamental for normal homeostasis. The discovery of microRNAs (miRNAs) as a new class of small non-protein-coding RNAs that control gene expression post-transcriptionally by binding to various mRNA targets suggests that these tiny RNA molecules likely act as molecular switches in the extensive regulatory web that involves thousands of transcripts. Most importantly, accumulating evidence suggests that numerous microRNAs are aberrantly expressed in human cancers. In this review, we discuss the emergent roles of microRNAs as switches that function to turn on/off known cellular microcircuits. We outline recent compelling evidence that deregulated microRNA-mediated control of cellular microcircuits cooperates with other well-established regulatory mechanisms to confer the hallmark traits of the cancer cell. Furthermore, these exciting insights into aberrant microRNA control in cancer-associated circuits may be exploited for cancer therapies that will target deregulated miRNA switches. PMID:19561119

  1. Construction of implantable optical fibers for long-term optogenetic manipulation of neural circuits.

    Science.gov (United States)

    Sparta, Dennis R; Stamatakis, Alice M; Phillips, Jana L; Hovelsø, Nanna; van Zessen, Ruud; Stuber, Garret D

    2012-01-01

    In vivo optogenetic strategies have redefined our ability to assay how neural circuits govern behavior. Although acutely implanted optical fibers have previously been used in such studies, long-term control over neuronal activity has been largely unachievable. Here we describe a method to construct implantable optical fibers to readily manipulate neural circuit elements with minimal tissue damage or change in light output over time (weeks to months). Implanted optical fibers readily interface with in vivo electrophysiological arrays or electrochemical detection electrodes. The procedure described here, from implant construction to the start of behavioral experimentation, can be completed in approximately 2-6 weeks. Successful use of implantable optical fibers will allow for long-term control of mammalian neural circuits in vivo, which is integral to the study of the neurobiology of behavior. PMID:22157972

  2. Ultra-Fast All-Optical Self-Aware Protection Switching Based on a Bistable Laser Diode

    DEFF Research Database (Denmark)

    An, Yi; Vukovic, Dragana; Lorences Riesgo, Abel;

    2014-01-01

    We propose a novel concept of all-optical protection switching with link failure automatic awareness based on AOWFF. The scheme is experimentally demonstrated using a single MG-Y laser diode with a record switching time ~200 ps.......We propose a novel concept of all-optical protection switching with link failure automatic awareness based on AOWFF. The scheme is experimentally demonstrated using a single MG-Y laser diode with a record switching time ~200 ps....

  3. Nonlinear optical switching and optical limiting in colloidal CdSe quantum dots investigated by nanosecond Z-scan measurement

    Science.gov (United States)

    Valligatla, Sreeramulu; Haldar, Krishna Kanta; Patra, Amitava; Desai, Narayana Rao

    2016-10-01

    The semiconductor nanocrystals are found to be promising class of third order nonlinear optical materials because of quantum confinement effects. Here, we highlight the nonlinear optical switching and optical limiting of cadmium selenide (CdSe) quantum dots (QDs) using nanosecond Z-scan measurement. The intensity dependent nonlinear absorption and nonlinear refraction of CdSe QDs were investigated by applying the Z-scan technique with 532 nm, nanosecond laser pulses. At lower intensities, the nonlinear process is dominated by saturable absorption (SA) and it is changed to reverse saturable absorption (RSA) at higher intensities. The SA behaviour is attributed to the ground state bleaching and the RSA is ascribed to free carrier absorption (FCA) of CdSe QDs. The nonlinear optical switching behaviour and reverse saturable absorption makes CdSe QDs are good candidate for all-optical device and optical limiting applications.

  4. A silicon-on-glass single-pole-double-throw (SPDT) switching circuit integrated with a silicon-core metal-coated transmission line

    International Nuclear Information System (INIS)

    This paper presents a novel low-loss single-pole-double-throw (SPDT) switching circuit which integrates a silicon-core metal-coated coplanar waveguide (CPW) and two laterally moving switches in parallel. The circuit structure consists of single-crystal silicon as the core material and a thin layer of metal coated on the core surface to propagate the RF signal. The influences of the material property and the process variation on the RF performance of the silicon-core metal-coated CPW is analyzed in detail, including the silicon-core resistivity, the spreading metal on the substrate and the recess etching depth. Based on this analysis, the low-loss SPDT switching circuit is designed and fabricated using high-resistivity silicon (HRSi) as the core material and Pyrex 7740 glass as the substrate. The pull-in voltage of the laterally moving switch is 12.35 V. The insertion loss of the laterally moving switch is less than 1 dB up to 40 GHz. Both the return loss and the isolation are higher than 22 dB up to 40 GHz. The SPDT switching circuit has an insertion loss of less than 1 dB up to 22 GHz. The return loss is 17 dB and the isolation is 25 dB at 25 GHz. A silicon-on-glass (SOG)-based substrate-transfer micromachining process is developed for the SPDT switching circuit fabrication, which has the advantages of single mask, high design flexibility and low signal propagation losses

  5. Printed Circuit Board Embedded Inductors for Very High Frequency Switch-Mode Power Supplies

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.;

    2013-01-01

    The paper describes the design of three different structures for printed circuit board embedded inductors. Direct comparison of spirals, solenoids and toroids are made with regard to inductance, dc and ac resistance, electromagnetic field and design flexibility. First the equations for the impeda......The paper describes the design of three different structures for printed circuit board embedded inductors. Direct comparison of spirals, solenoids and toroids are made with regard to inductance, dc and ac resistance, electromagnetic field and design flexibility. First the equations...

  6. Optical Waveguide Switches Employing Total-Internal-Reflection (TIR) Effect (Invited Paper)

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper, our recent research work on the total-internal-reflection optical switch is presented. The thermo-optic effect of polymeric materials and the photon-induced carrier effect of GaAlAs/GaAs are used in our devices.

  7. INSTITUCIONALIZAÇÃO E DESINSTITUCIONALIZAÇÃO DE PRÁTICAS SOCIAIS: O CASO DAS TECNOLOGIAS VOIP E CIRCUIT SWITCHED INSTITUTIONALIZATION AND DEINSTITUTIONALIZATION OF SOCIAL PRACTICES: THE CASE OF VOIP AND CIRCUIT SWITCHED TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    João Armênio Neto

    2009-12-01

    Full Text Available O objetivo do presente estudo foi verificar o processo de institucionalização da tecnologia VoIP e a correspondente desinstitucionalização da tecnologia circuit switched na estratégia de produtos da Organização Alfa, no âmbito global e no contexto brasileiro, no período compreendido entre 1993 e 2008. Com base no quadro teórico de referência da teoria institucional, as tipologias de Oliver (1991, 1992 foram utilizadas para analisar pressões ambientais (políticas, sociais e instrumentais e respostas estratégicas (aquiescência, compromisso, esquivança, desafio e manipulação. A perspectiva da pesquisa é longitudinal, com uso do método de estudo de caso e procedimentos qualitativos para coleta, tratamento e análise dos dados. A coleta de dados realizou-se mediante acesso a fontes secundárias e por meio de entrevistas semi-estruturadas com empregados da Organização Alfa. Os dados demonstram a ocorrência de um processo de substituição da tecnologia circuit switched pela tecnologia VoIP em combinação com práticas associadas a vendas, marketing, P&D e serviços. Verificou-se que a mudança vem ocorrendo de forma gradual, passando por respostas de desafio, esquivança, compromisso e aquiescência, também com certas nuances de manipulação. A situação no final do período estudado demonstra que o processo de institucionalização da tecnologia VoIP na Organização Alfa encontra-se em estágio mais avançado do que no âmbito do mercado em que ela atua. The purpose of this study was to analyze the process of institutionalization of VoIP and deinstitutionalization of circuit switched technologies in Organization Alpha's product strategy, both in the global and the Brazilian context, from 1993 to 2008. Based on the institutional theory's theoretical framework, Oliver's typologies (1991, 1992 were used to understand the environmental (politics, social and instrumental pressures and the organization's strategic responses

  8. Dynamics of all-optically switched micropillar resonances

    CERN Document Server

    Thyrrestrup, Henri; Ctistis, Georgios; Claudon, Julien; Vos, Willem L

    2014-01-01

    Here we do frequency and time resolved switching of a single GaAs/AlGa micropillar cavity with a pillar diameter of 6 mu using a ultrafast pump-probe setup. The switching is achieved by two-photon excitation of free carriers by an femtosecond pump pulse. We observe a simultaneously frequency shift of the first two transverse micropillar modes and obtain high resolution frequency traces of the two resonances in time. A difference in the the maximum switching magnitude of 12% point is caused by spatial inhomogeneous excitation of carriers in the pillar. The relaxation dynamic of the two resonances show a strongly non-exponential decay. We interpret the non-exponential dynamics in term of a second order decay model for the spontaneous recombination of electron and hole for the free carriers and a slow free carrier trapping time of ~300 ps.

  9. Integrated optical and electronic interconnect printed circuit board manufacturing

    OpenAIRE

    Selviah, D. R.; Fernández, F. A.; Papakonstantinou, I.; Wang, K.; Bagshiahi, H.; Walker, A. C.; McCarthy, A.; Suyal, H; Hutt, D.A.; Conway, P. P.; Chappell, J.; Zakariyah, S. S.; Milward, D

    2008-01-01

    Introduction: At high bit rates copper tracks in printed circuit boards (PCBs) suffer severe loss and pulse distortion due to radiation of electromagnetic waves, dispersion and bandwidth limitations. The loss can be overcome to some extent by transmitting higher power pulses and by changing the dielectric constant and loss tangent of the PCB substrate material. However, high power pulses consume power and can cause electro-migration which reduces the board lifetime, although the copper tracks...

  10. NATO Advanced Research Workshop on Optical Switching in Low-Dimensional Systems

    CERN Document Server

    Bányai, L

    1989-01-01

    This book contains all the papers presented at the NATO workshop on "Optical Switching in Low Dimensional Systems" held in Marbella, Spain from October 6th to 8th, 1988. Optical switching is a basic function for optical data processing, which is of technological interest because of its potential parallelism and its potential speed. Semiconductors which exhibit resonance enhanced optical nonlinearities in the frequency range close to the band edge are the most intensively studied materials for optical bistability and fast gate operation. Modern crystal growth techniques, particularly molecular beam epitaxy, allow the manufacture of semiconductor microstructures such as quantum wells, quantum wires and quantum dots in which the electrons are only free to move in two, one or zero dimensions, of the optically excited electron-hole pairs in these low respectively. The spatial confinement dimensional structures gives rise to an enhancement of the excitonic nonlinearities. Furthermore, the variations of the microstr...

  11. A New All-Optical Switching Node Including Virtual Memory and Synchronizer

    Directory of Open Access Journals (Sweden)

    Selma Batti

    2010-02-01

    Full Text Available This paper presents an architecture for an all optical switching node. The architecture is suitable for optical packet and optical burst switching and provides appropriate contention resolution schemes and QoS guarantees. A concept, called virtual memory, is developed to allow controllable and reasonable periods for delaying optical traffics. Related to its implementation, several engineering issues are discussed, including the use of loopbased optical delay lines, fiber Bragg gratings, and limited number of signal amplifications. In particular, two implementations using optical flip-flop and laser neuron network based control units are analyzed. This paper also discusses the implementation and performance of an alloptical synchronizer that is able to synchronize arriving data units to be aligned on the clock signal associated with the beginning time of slots, in the node, with an acceptable error.

  12. Platforms for integrated nonlinear optics compatible with silicon integrated circuits

    CERN Document Server

    Moss, David J

    2014-01-01

    Nonlinear photonic chips are capable of generating and processing signals all-optically with performance far superior to that possible electronically - particularly with respect to speed. Although silicon has been the leading platform for nonlinear optics, its high two-photon absorption at telecommunications wavelengths poses a fundamental limitation. We review recent progress in CMOS-compatible platforms for nonlinear optics, focusing on Hydex glass and silicon nitride and briefly discuss the promising new platform of amorphous silicon. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation, ultrafast optical pulse generation and measurement. We highlight their potential future impact as well as the challenges to achieving practical solutions for many key applications.

  13. Development of optical switching readout X-ray detector for high-speed imaging

    International Nuclear Information System (INIS)

    In this study, we demonstrated the feasibility of an X-ray detector with a dual amorphous-selenium (a-Se) layer using an optical switching readout for high-speed X-ray imaging. The X-ray detector consists of a negative voltage bias electrode; a thick a-Se layer for the photoelectric conversion of X-ray photons; an As2Se3 layer employed as an electron-trapping layer for accumulating latent images; a thin a-Se layer for optical readout; alternate opaque and transparent electrodes; and an optical light source for the optical switching readout. The line light of the optical light source, which has a peak wavelength of 470 nm, is operated line by line using electrical scanning for high-speed X-ray imaging. The developed X-ray detector has a pixel pitch of 200 μm with 512 channels. -- Highlights: •The feasibility of X-ray detector for high-speed imaging was demonstrated. •An a-Se was used for optical switching layer for signal charge readout. •As2Se3 layer was employed as electron-trapping layer for accumulating latent images. •The surface light source of blue lights was fabricated for optical switching readout. •The 2D array of readout light can be emitted linearly and scanned electrically line by line

  14. Comments on: Optical computation based on nonlinear total reflectional optical switch at the interface

    Indian Academy of Sciences (India)

    Y A Zaghloul

    2015-12-01

    As we read the paper by Jianqi Zhang and Huan Xu, Pramana – J. Phys. 72, 547 (2009), two issues became clear, that warranted writing this comment. First, the switch, which is the main building block of the devices, and which is used to route the signal, does not work as explained in Section 4.1. Accordingly, the optical router does not work as explained, either. In addition, the half adder does not work as explained and a completely different Truth Table is obtained. The full adder is left to the reader as an exercise. Secondly, the previously published work, which is closely related to the work reported, was not referenced or discussed. In the following paragraphs we discuss each issue in some detail to give the authors the opportunity to better explain their work and clear such issues.

  15. An all-optical spatial light modulator for field-programmable silicon photonic circuits

    CERN Document Server

    Bruck, Roman; Lalanne, Philippe; Mills, Ben; Thomson, David J; Mashanovich, Goran Z; Reed, Graham T; Muskens, Otto L

    2016-01-01

    Reconfigurable photonic devices capable of routing the flow of light enable flexible integrated-optic circuits that are not hard-wired but can be externally controlled. Analogous to free-space spatial light modulators, we demonstrate all-optical wavefront shaping in integrated silicon-on-insulator photonic devices by modifying the spatial refractive index profile of the device employing ultraviolet pulsed laser excitation. Applying appropriate excitation patterns grants us full control over the optical transfer function of telecommunication-wavelength light travelling through the device, thus allowing us to redefine its functionalities. As a proof-of-concept, we experimentally demonstrate routing of light between the ports of a multimode interference power splitter with more than 97% total efficiency and negligible losses. Wavefront shaping in integrated photonic circuits provides a conceptually new approach toward achieving highly adaptable and field-programmable photonic circuits with applications in optica...

  16. Optimized design and fabrication of nanosecond response electro optic switch based on ultraviolet-curable polymers

    Institute of Scientific and Technical Information of China (English)

    赵旭亮; 岳远斌; 刘通; 孙健; 王希斌; 孙小强; 陈长鸣; 张大明

    2015-01-01

    A nanosecond response waveguide electro-optic (EO) switch based on ultraviolet (UV) sensitive polymers of Norland optical adhesive (NOA73) and Dispersed Red 1 (DR1) doped SU-8 (DR1/SU-8) is designed and fabricated. The absorption properties, refractive indexes, and surface morphologies of NOA73 film are characterized. The single-mode transmission condition is computed by the effective index method, and the percentage of optical field distributed in EO layer is optimized to be 93.78%. By means of spin-coating, thermal evaporation, photolithography, and inductively coupled plasma etching, a Mach–Zehnder inverted-rib waveguide EO switch with micro-strip line electrode is fabricated on a silicon substrate. Scanning electron microscope characterization proves the physic-chemical compatibility between NOA73 cladding and DR1/SU-8 core material. The optical transmission loss of the fabricated switch is measured to be 2.5 dB/cm. The rise time and fall time of switching are 3.199 ns and 2.559 ns, respectively. These results indicate that the inverted-rib wave-guide based on UV-curable polymers can effectively reduce the optical transmission loss and improve the time response performance of an EO switch.

  17. Quasi-Optical Network Analyzers and High-Reliability RF MEMS Switched Capacitors

    Science.gov (United States)

    Grichener, Alexander

    The thesis first presents a 2-port quasi-optical scalar network analyzer consisting of a transmitter and receiver both built in planar technology. The network analyzer is based on a Schottky-diode mixer integrated inside a planar antenna and fed differentially by a CPW transmission line. The antenna is placed on an extended hemispherical high-resistivity silicon substrate lens. The LO signal is swept from 3-5 GHz and high-order harmonic mixing in both up- and down- conversion mode is used to realize the 15-50 GHz RF bandwidth. The network analyzer resulted in a dynamic range of greater than 40 dB and was successfully used to measure a frequency selective surface with a second-order bandpass response. Furthermore, the system was built with circuits and components for easy scaling to millimeter-wave frequencies which is the primary motivation for this work. The application areas for a millimeter and submillimeter-wave network analyzer include material characterization and art diagnostics. The second project presents several RF MEMS switched capacitors designed for high-reliability operation and suitable for tunable filters and reconfigurable networks. The first switched-capacitor resulted in a digital capacitance ratio of 5 and an analog capacitance ratio of 5-9. The analog tuning of the down-state capacitance is enhanced by a positive vertical stress gradient in the the beam, making it ideal for applications that require precision tuning. A thick electroplated beam resulted in Q greater than 100 at C to X-band frequencies, and power handling of 0.6-1.1 W. The design also minimized charging in the dielectric, resulting in excellent reliability performance even under hot-switched and high power (1 W) conditions. The second switched-capacitor was designed without any dielectric to minimize charging. The device was hot-switched at 1 W of RF power for greater than 11 billion cycles with virtually no change in the C-V curve. The final project presents a 7-channel

  18. A novel graphene oxide-polyimide as optical waveguide material: Synthesis and thermo-optic switch properties

    Science.gov (United States)

    Cao, Tianlin; Zhao, Fanyu; Da, Zulin; Qiu, Fengxian; Yang, Dongya; Guan, Yijun; Cao, Guorong; Zhao, Zerun; Li, Jiaxin; Guo, Xiaotong

    2016-10-01

    In this work, a novel graphene oxide-polyimide (GOPI) as optical waveguide material was prepared. The structure, mechanical, thermal property and morphology of the GOPI was characterized by using fourier transform infrared, UV-visible spectroscopy, near-infrared spectrum, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscope and transmission electron microscopy. The thermo-optic coefficients (dn/dT) are -9.16 × 10-4 (532 nm), -7.56 × 10-4 (650 nm) and -4.82 × 10-4 (850 nm) °C-1, respectively. Based on the thermo-optic effect of prepared GOPI as waveguide material, a Y-branch with branching angle of 0.143° and Mach-Zehnder thermo-optic switches were designed. Using finite difference beam propagation method (FD-BPM) method, the simulation results such as power consumptions and response times of two different thermo-optic switches were obtained.

  19. An analytical model of pipelined circuit switching in hypercubes in the presence of hot spot traffic

    OpenAIRE

    Safaei, F.; Khonsari, A.; Fathy, M.; Ould-Khaoua, M.

    2005-01-01

    Several recent studies have revealed that PCS can provide superior performance characteristics over wormhole switching under uniform traffic. Analytical model of PCS for common networks (e.g., hypercube) under uniform traffic pattern have recently been reported in the literature. In this paper we propose an analytical model of PCS in the hypercube network augmented with virtual channel in the presence of hot spot traffic. The model has a good agreement with simulation experiments.

  20. SIMPLIFIED METHOD FOR CALCULATING CLOSING IN OF SWITCH-GEAR FLEXIBLE BUSES AT SHORT CIRCUIT BY IMPULSE OF ELECTRODYNAMIC FORCES

    Directory of Open Access Journals (Sweden)

    I. I. Sergey

    2005-01-01

    Full Text Available The paper contains description of a simplified method for calculating closing-in of switch-gear flexible buses at short circuit. The developed method is based on integral and energy principles of  mechanics. In order to increase accuracy of the calculation corrections factors are introduced in an explicit formula for calculation of maximum horizontal deviations. These factors have been obtained with the help of a computer program that realized numerical method for calculating closing-in of wires by flexible thread levels.Diagrams are constructed with the purpose to find ymax and criteria of electro-dynamic resistance of flexible buses (permissible impulse of electro-dynamic forces and current of electro-dynamic resistance is determined.

  1. From Boolean logic to switching circuits and automata. Towards modern information technology

    Energy Technology Data Exchange (ETDEWEB)

    Stankovic, Radomir S. [Nis Univ. (RS). Dept. of Computer Science; Astola, Jaakko [Tampere Univ. of Technology (Finland). Dept. of Signal Processing

    2011-07-01

    Logic networks and automata are facets of digital systems. The change of the design of logic networks from skills and art into a scientific discipline was possible by the development of the underlying mathematical theory called the Switching Theory. The fundamentals of this theory come from the attempts towards an algebraic description of laws of thoughts presented in the works by George J. Boole and the works on logic by Augustus De Morgan. As often the case in engineering, when the importance of a problem and the need for solving it reach certain limits, the solutions are searched by many scholars in different parts of the word, simultaneously or at about the same time, however, quite independently and often unaware of the work by other scholars. The formulation and rise of Switching Theory is such an example. This book presents a brief account of the developments of Switching Theory and highlights some less known facts in the history of it. The readers will find the book a fresh look into the development of the field revealing how difficult it has been to arrive at many of the concepts that we now consider obvious. Researchers in the history or philosophy of computing will find this book a valuable source of information that complements the standard presentations of the topic. (orig.)

  2. Experimental Demonstration of Optical Switching of Tbit/s Data Packets for High Capacity Short-Range Networks

    DEFF Research Database (Denmark)

    Medhin, Ashenafi Kiros; Kamchevska, Valerija; Hu, Hao;

    2015-01-01

    Record-high 1.28-Tbit/s optical data packets are experimentally switched in the optical domain using a LiNbO3 switch. An in-band notch-filter labeling scheme scalable to 65,536 labels is employed and a 3-km transmission distance is demonstrated.......Record-high 1.28-Tbit/s optical data packets are experimentally switched in the optical domain using a LiNbO3 switch. An in-band notch-filter labeling scheme scalable to 65,536 labels is employed and a 3-km transmission distance is demonstrated....

  3. Patterning Effects in Ultrafast All-Optical Photonic Crystal Nanocavity Switches

    DEFF Research Database (Denmark)

    Heuck, Mikkel; Kristensen, Philip Trøst; Mørk, Jesper

    2011-01-01

    All-optical switches are expected to play a key role in increasing the bandwidth of future communication networks by replacing slower electronic components for certain signal processing tasks. Previous work has demonstrated the possibility of switching a single pulse [1,2]. However, a more...... is on a photonic crystal material system, which facilitates a high level of integration with other components such as waveguides, light sources, beam splitters, etc....

  4. Design of buffer structure at core nodes in optical burst switching

    Institute of Scientific and Technical Information of China (English)

    LI Lei; ZHANG Min-gde; SUN Xiao-han

    2006-01-01

    Reasonable and effective buffer structures are proposed in core routers /nodes of optical burst switching.Based on the model of burst traffics and their contentions,the basic qualifications for the design of buffer structures are concluded.With these qualifications,buffer and switch integrated structures are proposed;and by conclusion and expansion,the classification rules of buffer structures are also proposed from different angles.The schemes to integrate structures are analyzed and simulated.

  5. Optimum design of a polymer electro-optic microring resonator switch

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Novel transfer functions are presented for a polymer electro-optic microring resonator switches. The resonating process of the light in the microring is simulated using the formulas. Then the optimization of the structural parameters is performed,and the characteristics are analyzed, such as the resonance time, output spectrum, operation voltage, insertion loss and crosstalk were analyzed. The simulation results show that the designed device exhibits favorable switching functions.

  6. Effects of graphene on electro-optic switching and spontaneous polarization of a ferroelectric liquid crystal

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Rajratan, E-mail: basu@usna.edu [Department of Physics, Soft-matter and Nanomaterials Laboratory, The United States Naval Academy, Annapolis, Maryland 21402 (United States)

    2014-09-15

    A small quantity of graphene flakes was doped in a ferroelectric liquid crystal (FLC), and the field-induced ferroelectric electro-optic switching was found to be significantly faster in the FLC + graphene hybrid than that of the pure FLC. Further studies revealed that the suspended graphene flakes enhanced the FLC's spontaneous polarization by improving smectic-C ordering resulting from the π–π electron stacking, and reduced rotation viscosity by trapping some of the free ions of the FLC media. These effects coherently impacted the FLC-switching phenomenon, enabling the FLC molecules to switch faster on reversing an external electric field.

  7. Performance Trade-Offs for Wavelength Striping Optical Switching Using a Novel Star Architecture

    Directory of Open Access Journals (Sweden)

    Enrique Rodriguez-Colina

    2016-01-01

    Full Text Available This work describes various performance trade-offs that arise from the use of a technique for optical switching under various network topologies. Such switching operation can be summarized as follows: (a user data are divided into fixed-length fragments, (b each fragment is assigned to a different wavelength, and (c all wavelengths are simultaneously switched to the egress links. This concept of dividing user data into several wavelengths to be simultaneously switched is called wavelength striping and its purpose is to reduce latency and increase throughput for short distance interconnects. We depart from previous work where a building block implementing this basic switching function has been built around semiconductor optical amplifiers (SOAs. In this paper, we investigate diverse trade-offs that arise from the use of this switching approach in different network topologies. One of the main issues addressed in this paper is the relation between cascadability and bit error rate (BER. In this case, our results indicate that a switch fabric can cascade up to five stages without exceeding a BER of 10−9 and without incurring in power budget problems. We also show that the performance degradation, introduced by cascading SOAs, can be compensated with a star interconnect architecture that is introduced. Other issues addressed in this paper are the effect of scalability on cost and the effect of latency on TCP performance and reliability.

  8. Some Advances in the Circuit Modeling of Extraordinary Optical Transmission

    OpenAIRE

    Medina, F.; Mesa, F; Rodriguez-Berral, R.

    2009-01-01

    The phenomenon of extraordinary optical transmission (EOT) through electrically small holes perforated on opaque metal screens has been a hot topic in the optics community for more than one decade. This experimentally observed frequency-selective enhanced transmission of electromagnetic power through holes, for which classical Bethe's theory predicts very poor transmission, later attracted the attention of engineers working on microwave engineering or applied electromagnetics. Extraordinary t...

  9. Broadband optically controlled switching effect in a microfluid-filled photonic bandgap fiber

    Science.gov (United States)

    Guo, Junqi; Liu, Yan-ge; Wang, Zhi; Luo, Mingming; Huang, Wei; Han, Tingting; Liu, Xiaoqi

    2016-05-01

    Broadband optically controlled switching in a microfluid-filled photonic bandgap fiber (MF-PBGF) was observed and investigated. The MF-PBGF was formed by infusing a temperature-sensitive high-index fluid into all of the cladding holes of a microstructured optical fiber (MOF). The fiber was then side pumped with a 532 nm continuous wave laser. An extinction ratio of greater than 20 dB at most of the bandgap wavelengths (more than 200 nm) was obtained with a switching power of ∼147 mW. Theoretical and experimental investigations revealed that the effect originated from changes in the temperature gradient induced by heat absorption of the fiber coating with laser illumination. These investigations offer a new and simple approach to achieve wideband and flexible all-optical fiber switching devices without using any photosensitive materials.

  10. 三相绕组切换电路分析与设计%Analysis and Design of Thiphase Winding Switching Circuit

    Institute of Scientific and Technical Information of China (English)

    罗宏浩; 王福兴; 姜红军

    2012-01-01

    Under the circumstances that volume and power are limited in armored vehicles, raising low speed large torque and widening flux-weakening range become conflict inevitably in permanent magnet motors. The motor winding switching method is adopted to resolve this problem. A switching circuit design is proposed and the dynamic process of switching circuit is analyzed with Muhisim software. What' s more, a switching control system is constructed based on zero current switching to fulfill triphase winding switching and observe the current waveforms. The experimental results show that the switching between serial and parallel connection in the circuit is very rapid and the voltage impulsion is eliminated during the switching process.%针对在装甲车辆中体积、功率受限条件下,永磁电动机提升低速转矩与拓宽弱磁工作范围难以兼顾的问题,提出了采用电动机绕组换接的方法。提出了一种切换电路的设计方案,采用电路仿真软件Muhisim分析了切换电路的动态工作过程。在此基础上,构建了一套适用于三相绕组切换的零电流切换控制系统,可通过上位机观测电路中的电流波形,并实现对绕组的串、并联结构进行切换控制。试验结果表明:该电路可快速实现绕组的串/并联切换,而且基本上不会产生电压冲击。

  11. 5.8kV SiC PiN Diode for Switching of High-Efficiency Inductive Pulsed Plasma Thruster Circuits

    Science.gov (United States)

    Toftul, Alexandra; Polzin, Kurt A.; Hudgins, Jerry L.

    2014-01-01

    Inductive Pulsed Plasma Thruster (IPPT) pulse circuits, such as those needed to operate the Pulsed Inductive Thruster (PIT), are required to quickly switch capacitor banks operating at a period of µs while conducting current at levels on the order of at least 10 kA. [1,2] For all iterations of the PIT to date, spark gaps have been used to discharge the capacitor bank through an inductive coil. Recent availability of fast, high-power solid state switching devices makes it possible to consider the use of semiconductor switches in modern IPPTs. In addition, novel pre-ionization schemes have led to a reduction in discharge energy per pulse for electric thrusters of this type, relaxing the switching requirements for these thrusters. [3,4] Solid state switches offer the advantage of greater controllability and reliability, as well as decreased drive circuit dimensions and mass relative to spark gap switches. The use of solid state devices such as Integrated Gate Bipolar Transistors (IGBTs), Gate Turn-off Thyristors (GTOs) and Silicon-Controlled Rectifiers (SCRs) often involves the use of power diodes. These semiconductor devices may be connected antiparallel to the switch for protection from reverse current, or used to reduce power loss in a circuit by clamping off current ringing. In each case, higher circuit efficiency may be achieved by using a diode that is able to transition, or 'switch,' from the forward conducting state ('on' state) to the reverse blocking state ('off' state) in the shortest amount of time, thereby minimizing current ringing and switching losses. Silicon Carbide (SiC) PiN diodes offer significant advantages to conventional fast-switching Silicon (Si) diodes for high power and fast switching applications. A wider band gap results in a breakdown voltage 10 times that of Si, so that a SiC device may have a thinner drift region for a given blocking voltage. [5] This leads to smaller, lighter devices for high voltage applications, as well as reduced

  12. On the fly all-optical packet switching based on hybrid WDM/OCDMA labeling scheme

    Science.gov (United States)

    Brahmi, Houssem; Giannoulis, Giannis; Menif, Mourad; Katopodis, Vasilis; Kalavrouziotis, Dimitrios; Kouloumentas, Christos; Groumas, Panos; Kanakis, Giannis; Stamatiadis, Christos; Avramopoulos, Hercules; Erasme, Didier

    2014-02-01

    We introduce a novel design of an all-optical packet routing node that allows for the selection and forwarding of optical packets based on the routing information contained in hybrid wavelength division multiplexing/optical code division multiple access (WDM/OCDMA) labels. A stripping paradigm of optical code-label is adopted. The router is built around an optical-code gate that consists in an optical flip-flop controlled by two fiber Bragg grating correlators and is combined with a Mach-Zehnder interferometer (MZI)-based forwarding gate. We experimentally verify the proof-of-principle operation of the proposed self-routing node under NRZ and OCDMA packet traffic conditions. The successful switching of elastic NRZ payload at 40 Gb/s controlled by DS-OCDMA coded labels and the forwarding operation of encoded data using EQC codes are presented. Proper auto-correlation functions are obtained with higher than 8.1 dB contrast ratio, suitable to efficiently trigger the latching device with a contrast ratio of 11.6 dB and switching times below 3.8 ns. Error-free operation is achieved with 1.5 dB penalty for 40 Gb/s NRZ data and with 2.1 dB penalty for DS-OCDMA packets. The scheme can further be applied to large-scale optical packet switching networks by exploiting efficient optical coders allocated at different WDM channels.

  13. Traffic analysis and signal processing in optical packet switched networks

    DEFF Research Database (Denmark)

    Fjelde, Tina

    2002-01-01

    Gbit/s demultiplexing and 2x10 to 20 Gbit/s multiplexing. Lastly, the IWC’s capabilities as an optical logic gate for enabling more complex signal processing are demonstrated and four applications hereof are discussed. Logic OR and AND are verified in full at 10 Gbit/s using PRBS sequences coupled......, involving all-optical pattern recognition by bit-wise sampling at multiple wavelengths, optical identification of bit differences in data segments through a combination of logic XOR and AND, and all optical bit sequence replacement through logic OR and AND. The schemes enable important signal processing...

  14. Sub-picosecond optical switching with a negative index metamaterial

    Energy Technology Data Exchange (ETDEWEB)

    Dani, Keshav M [Los Alamos National Laboratory; Upadhya, Prashant C [Los Alamos National Laboratory; Zahyum, Ku [CHTM-UNM

    2009-01-01

    Development of all-optical signal processing, eliminating the performance and cost penalties of optical-electrical-optical conversion, is important for continu,ing advances in Terabits/sec (Tb/s) communications.' Optical nonlinearities are generally weak, traditionally requiring long-path, large-area devicesl,2 or very high-Q, narrow-band resonator structures.3 Optical metamaterials offer unique capabilities for optical-optical interactions. Here we report 600 femtosecond (fs) all-optical modulation using a fIShnet (2D-perforated metallamorphous-Si (a-Si)/metal film stack) negative-index meta material with a structurally tunable broad-band response near 1.2 {micro}m. Over 20% modulation (experimentally limited) is achieved in a path length of only 116 nm by photo-excitation of carriers in the a-Si layer. This has the potential for Tb/s aU-optical communication and will lead to other novel, compact, tunable sub-picosecond (ps) photonic devices.

  15. Flexible low-voltage organic integrated circuits with megahertz switching frequencies (Presentation Recording)

    Science.gov (United States)

    Zschieschang, Ute; Takimiya, Kazuo; Zaki, Tarek; Letzkus, Florian; Richter, Harald; Burghartz, Joachim N.; Klauk, Hagen

    2015-09-01

    A process for the fabrication of integrated circuits based on bottom-gate, top-contact organic thin-film transistors (TFTs) with channel lengths as short as 1 µm on flexible plastic substrates has been developed. In this process, all TFT layers (gate electrodes, organic semiconductors, source/drain contacts) are patterned with the help of high-resolution silicon stencil masks, thus eliminating the need for subtractive patterning and avoiding the exposure of the organic semiconductors to potentially harmful organic solvents or resists. The TFTs employ a low-temperature-processed gate dielectric that is sufficiently thin to allow the TFTs and circuits to operate with voltages of about 3 V. Using the vacuum-deposited small-molecule organic semiconductor 2,9-didecyl-dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10 DNTT), TFTs with an effective field-effect mobility of 1.2 cm2/Vs, an on/off current ratio of 107, a width-normalized transconductance of 1.2 S/m (with a standard deviation of 6%), and a signal propagation delay (measured in 11-stage ring oscillators) of 420 nsec per stage at a supply voltage of 3 V have been obtained. To our knowledge, this is the first time that megahertz operation has been achieved in flexible organic transistors at supply voltages of less than 10 V. In addition to flexible ring oscillators, we have also demonstrated a 6-bit digital-to-analog converter (DAC) in a binary-weighted current-steering architecture, based on TFTs with a channel length of 4 µm and fabricated on a glass substrate. This DAC has a supply voltage of 3.3 V, a circuit area of 2.6 × 4.6 mm2, and a maximum sampling rate of 100 kS/s.

  16. Ultrafast low-energy all-optical switching using a photonic-crystal asymmetric Fano structure

    DEFF Research Database (Denmark)

    Yu, Yi; Hu, Hao; Oxenløwe, Leif Katsuo;

    2015-01-01

    We experimentally demonstrate 20 Gbit/s all-optical switching with low-energy consumption using a simple and ultra-compact InP photonic-crystal structure by employing a well-engineered Fano resonance in combination with broken mirror symmetry.......We experimentally demonstrate 20 Gbit/s all-optical switching with low-energy consumption using a simple and ultra-compact InP photonic-crystal structure by employing a well-engineered Fano resonance in combination with broken mirror symmetry....

  17. Fast and efficient silicon thermo-optic switching based on reverse breakdown of pn junction.

    Science.gov (United States)

    Li, Xianyao; Xu, Hao; Xiao, Xi; Li, Zhiyong; Yu, Yude; Yu, Jinzhong

    2014-02-15

    We propose and demonstrate a fast and efficient silicon thermo-optic switch based on reverse breakdown of the pn junction. Benefiting from the direct heating of silicon waveguide by embedding the pn junction into the waveguide center, fast switching with on/off time of 330 and 450 ns and efficient thermal tuning of 0.12  nm/mW for a 20 μm radius microring resonator are achieved, indicating a high figure of merit of only 8.8  mW·μs. The results here show great potential for application in the future optical interconnects.

  18. Optical switching of electron transport in a waveguide-QED system

    Science.gov (United States)

    Abdullah, Nzar Rauf; Tang, Chi-Shung; Manolescu, Andrei; Gudmundsson, Vidar

    2016-10-01

    Electron switching in waveguides coupled to a photon cavity is found to be strongly influenced by the photon energy and polarization. Therefore, the charge dynamics in the system is investigated in two different regimes, for off-resonant and resonant photon fields. In the off-resonant photon field, the photon energy is smaller than the energy spacing between the first two lowest subbands of the waveguide system, the charge splits between the waveguides implementing a √{ NOT }-quantum logic gate action. In the resonant photon field, the charge is totally switched from one waveguide to the other due to the appearance of photon replica states of the first subband in the second subband region instigating a quantum-NOT transition. In addition, the importance of the photon polarization to control the charge motion in the waveguide system is demonstrated. The idea of charge switching in electronic circuits may serve to built quantum bits.

  19. Acousto-optic and opto-acoustic modulation in piezo-optomechanical circuits

    CERN Document Server

    Balram, Krishna C; Ilic, B Robert; Kyhm, Ji-Hoon; Song, Jin Dong; Srinivasan, Kartik

    2016-01-01

    Acoustic wave devices provide a promising chip-scale platform for efficiently coupling radio frequency (RF) and optical fields. Here, we use an integrated piezo-optomechanical circuit platform that exploits both the piezoelectric and photoelastic coupling mechanisms to link 2.4 GHz RF waves to 194 THz (1550 nm) optical waves, through coupling to propagating and localized 2.4 GHz acoustic waves. We demonstrate acousto-optic modulation, resonant in both the optical and mechanical domains, in which waveforms encoded on the RF carrier are mapped to the optical field. We also show opto-acoustic modulation, in which the application of optical pulses gates the transmission of propagating acoustic waves. The time-domain characteristics of this system under both pulsed RF and pulsed optical excitation are considered in the context of the different physical pathways involved in driving the acoustic waves, and modeled through the coupled mode equations of cavity optomechanics.

  20. Whispering-gallery microcavity semiconductor lasers suitable for photonic integrated circuits and optical interconnects

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The characteristics of whispering-gallery-like modes in the equilateral triangle and square microresonators are introduced,including directional emission triangle and square microlasers connected to an output waveguide.We propose a photonic interconnect scheme by connecting two directional emission microlasers with an optical waveguide on silicon integrated circuit chip.The measurement indicates that the triangle microlasers can work as a resonance enhanced photodetector for optical interconnect.

  1. 电路交换域数据采集系统的FPGA设计%FPGA Design of Circuit Switched Domain Data Acquisition System

    Institute of Scientific and Technical Information of China (English)

    何赞园; 王凯; 吉立新

    2014-01-01

    随着大数据应用的发展,从电路交换域获取数据也是丰富海量数据库的一个重要途径。为了提高电路交换域数据采集的效率,丰富采集手段,结合电路交换域数据通信的特点以及数据组包的要求,提出了一种基于FPGA实现电路交换域数据采集的设计方案,给出了FPGA的数据采集模型,并对该模型的组成模块进行了详细阐述,实现了数据从电路交换域到分组交换域的自动转换。测试结果表明,该数据采集系统丰富了时分复用线路数据采集的效率,实现了预期的功能。%Along with the development of big data applications,getting data from the circuit switched do-main is an important way to enrich the massive database. In order to improve the efficiency of circuit switched domain acquisition and enrich the collection means, according to the characteristics of circuit switched domain data requirements and data packet,an exchange field data acquisition circuit based on FP-GA design is proposed,FPGA data model is given and the modules of the model are described in detail. The automatic conversion from circuit switched domain data to the packet switched domain is realized. Test results show that the data acquisition system enriches the time division multiplexing( TDM) line efficiency of data collection,and achieves the desired function.

  2. All-optical switching in a symmetric three-waveguide coupler with phase-mismatched absorptive central waveguide.

    Science.gov (United States)

    Chen, Yijing; Ho, Seng-Tiong; Krishnamurthy, Vivek

    2013-12-20

    All-optical switching operation based on manipulation of absorption in a three-waveguide directional coupler is theoretically investigated. The proposed structure consists of one absorptive central waveguide and two identical passive side waveguides. Optically induced absorption change in the central waveguide effectively controls the coupling of light between the two side waveguides, leading to optical switching action. The proposed architecture alleviates the fabrication challenges and waveguide index matching conditions that limit previous demonstrations of similar switching schemes based on a two-waveguide directional coupler. The proposed device accommodates large modal index difference between absorptive and passive waveguides without compromising the switching extinction ratio.

  3. Architectures of electro-optical packet switched networks

    DEFF Research Database (Denmark)

    Berger, Michael Stubert

    2004-01-01

    of an additional speedup of 10%. Lastly, the address lookup and classification problem is addressed, and an IP lookup algorithm with low memory requirement and fast updates is presented. The scheme uses a combination of trie and tree search, which is efficient in memory usage because the structure contains exactly...... architecture for a buffered crossbar switch is presented. The architecture uses two levels of backpressure (flow control) with different constraints on round trip time. No additional scheduling complexity is introduced, and for the actual example shown, a reduction in memory of 75% was obtained at the cost...

  4. Transparent ceramic photo-optical semiconductor high power switches

    Science.gov (United States)

    Werne, Roger W.; Sullivan, James S.; Landingham, Richard L.

    2016-01-19

    A photoconductive semiconductor switch according to one embodiment includes a structure of sintered nanoparticles of a high band gap material exhibiting a lower electrical resistance when excited by light relative to an electrical resistance thereof when not exposed to the light. A method according to one embodiment includes creating a mixture comprising particles, at least one dopant, and at least one solvent; adding the mixture to a mold; forming a green structure in the mold; and sintering the green structure to form a transparent ceramic. Additional system, methods and products are also presented.

  5. Continuous or discrete attractors in neural circuits? A self-organized switch at maximal entropy

    CERN Document Server

    Bernacchia, Alberto

    2007-01-01

    A recent experiment suggests that neural circuits may alternatively implement continuous or discrete attractors, depending on the training set up. In recurrent neural network models, continuous and discrete attractors are separately modeled by distinct forms of synaptic prescriptions (learning rules). Here, we report a solvable network model, endowed with Hebbian synaptic plasticity, which is able to learn either discrete or continuous attractors, depending on the frequency of presentation of stimuli and on the structure of sensory coding. A continuous attractor is learned when experience matches sensory coding, i.e. when the distribution of experienced stimuli matches the distribution of preferred stimuli of neurons. In that case, there is no processing of sensory information and neural activity displays maximal entropy. If experience goes beyond sensory coding, processing is initiated and the continuous attractor is destabilized into a set of discrete attractors.

  6. ASE suppression of XeCl excimer laser MOPA system using UV electro-optical switch

    Science.gov (United States)

    Hu, Yun; Zhao, Xue-qing; Xue, Quan-xi; Wang, Da-hui; Zheng, Guo-xin; Hua, Heng-qi; Zhang, Yongsheng; Zhu, Yong-xiang; Xiao, Wei-wei; Wang, Li

    2013-05-01

    In high power eximer laser system, amplified spontaneous emission (ASE) decreases the signal contrast ratio severely, leads to waveform broadening and distortion, and impacts on accurate physical experiments. In this article, based on principle of short pulse generation by electro-optical (E-O) switch, a method for ASE suppression of laser amplifiers chain was established. A series of studies on UV electro-optical switches were carried out, and electro-optical (E-O) switches with high extinction ratio were developed. In the waveform clipping experiments of the first pre-amplifier, the extinction ratio of the single and cascaded dual E-O switch reaches 103 and 104 order of magnitude, the laser pulse signal contrast ratio was promoted to 105 and 106 level, respectively. In the experiments of single channel MOPA (Master Oscillator Power Amplifier system), the cascaded dual E-O switch was adopted to suppress ASE of the whole system, and a fine narrow pulse was obtained on the target surface, which gives out one effective solution to the problem of waveform amplification of the high power eximer laser system.

  7. A nonlinear plasmonic resonator for three-state all-optical switching

    KAUST Repository

    Amin, Muhammad

    2014-01-01

    A nonlinear plasmonic resonator design is proposed for three-state all-optical switching at frequencies including near infrared and lower red parts of the spectrum. The tri-stable response required for three-state operation is obtained by enhancing nonlinearities of a Kerr medium through multiple (higher order) plasmons excited on resonator\\'s metallic surfaces. Indeed, simulations demonstrate that exploitation of multiple plasmons equips the proposed resonator with a multi-band tri-stable response, which cannot be obtained using existing nonlinear plasmonic devices that make use of single mode Lorentzian resonances. Multi-band three-state optical switching that can be realized using the proposed resonator has potential applications in optical communications and computing. © 2014 Optical Society of America.

  8. Experimental study on an all-optical switching based on MF-NOLM

    Institute of Scientific and Technical Information of China (English)

    SONG Xue-peng; REN Xiao-min; ZHANG Xia; YANG Guang-qiang; HUANG Yong-qing

    2006-01-01

    In this paper,the experiment on an all-optical switching is reported based on a microstructure fiber(MF)-nonlinear optical loop mirror(NOLM).In the experiment,a 25-meter-long MF(γ=36W-1km-1@1 550 nm) is used as a nonlinear medium of the nonlinear optical loop mirror and the input signal is generated by a 10 GHz tunable picosecond laser source,with a full-width at half-maximum (FWHM) of 2 ps and centered at 1 550 nm.With the increase of input power,a π nonlinear phase shift is obtained by a 40/60 coupler in the experiment,but the same result can not be found by a 48/52 coupler.Additionally,the switching devices can also be used as an all-optical regeneration.

  9. Hybrid photonic integrated circuits for faster and greener optical communication networks

    Science.gov (United States)

    Stampoulidis, L.; Kehayas, E.; Zimmermann, L.

    2011-01-01

    We present current development efforts on hybrid photonic integration for new generation "faster and greener" Tb/scapacity optical networks. On the physical layer, we present the development of a versatile, silicon-based photonic integration platform that acts as a technology "blender" bringing together different material systems including III-V and silicon-based semiconductors. The platform is also used to implement the so-called O-to-O (optical-to-optical) functionalities by patterning low-loss passive components such as MMI couplers and delay interferometers. With these passive building blocks as well as the ability for hybrid assembly of active material, we demonstrate the fabrication of key optical transport and routing devices such as optical demodulators and all-optical wavelength converters. These devices can now be used to fabricate chip-scale 100 GbE transceiver PICs and Tb/s-capacity wavelength switching platforms.

  10. Photocurrent switching method based on photoisomerization of diarylethene layer for nondestructive readout of photochromic optical memory.

    Science.gov (United States)

    Tsujioka, Tsuyoshi; Onishi, Itaru; Natsume, Daisuke

    2010-07-10

    We report on photocurrent switching based on photoisomerization for the nondestructive readout of photochromic optical memory. The photoisomerization of a diarylethene (DAE) memory layer switched the photocurrent generated in a light-absorbing phthalocyanine layer upon irradiation of a laser light. This switching is based on the ionization potential change of the DAE molecules. Switching characteristics of the photocurrent were investigated for the laser light with a wavelength of 410 nm, 630 nm, or 780 nm. Excellent on-off ratios of the photocurrent were achieved by irradiation at 630 nm and 780 nm. When the pulsed laser light with a wavelength of 780 nm was repeatedly irradiated to the colored and uncolored memory devices, no change of the photocurrent signal levels was observed, even after 8 x 10(5) cycles, indicating a successful demonstration of the nondestructive readout.

  11. Optically-switched microwave filter with the use of photovaractors in self-bias mode

    OpenAIRE

    Szczepaniak, Zenon R.; Galwas, Bogdan A.; Malyshev, Sergei A.

    2001-01-01

    A new type of semiconductor optoelectronic device, which is called as photovaractor, was used in a self-bias mode of operation to obtain an optically-variable impedance. This approach allowed designing an optically-switched microwave band-pass filter. The use of the photovaractor in the microwave structure was investigated. The measurements of the photovaractor, the idea of the self-bias mode, and the simulations of the filter have been presented.

  12. Hybrid Wavelength Routed and Optical Packet Switched Ring Networks for the Metropolitan Area Network

    OpenAIRE

    Nord, Martin

    2005-01-01

    Increased data traffic in the metropolitan area network calls for new network architectures. This paper evaluates optical ring architectures based on optical packet switching, wavelength routing, and hybrid combinations of the two concepts. The evaluation includes overall throughput and fairness aspects in both uniform and unbalanced traffic scenarios, for both Poisson and bursty input traffic. Simulations show a trade-off between performance and complexity. Whilst the static wavelength route...

  13. Minimizing the Switch and Link Conflicts in an Optical Multi-stage Interconnection Network

    CERN Document Server

    Bhardwaj, Ved Prakash; Tyagi, Vipin

    2012-01-01

    Multistage Interconnection Networks (MINs) are very popular in switching and communication applications. A MIN connects N inputs to N outputs and is referred as an N \\times N MIN; having size N. Optical Multistage Interconnection Network (OMIN) represents an important class of Interconnection networks. Crosstalk is the basic problem of OMIN. Switch Conflict and Link Conflict are the two main reason of crosstalk. In this paper, we are considering both problems. A number of techniques like Optical window, Improved Window, Heuristic, Genetic, and Zero have been proposed earlier in this research domain. In this paper, we have proposed two algorithms called Address Selection Algorithm and Route Selection Algorithm (RSA). RSA is based on Improved Window Method. We have applied the proposed algorithms on existing Omega network, having shuffle-exchange connection pattern. The main functionality of ASA and RSA is to minimize the number of switch and link conflicts in the network and to provide conflict free routes.

  14. Lidar Electro-Optic Beam Switch with a Liquid Crystal Variable Retarder

    Science.gov (United States)

    Baer, James

    2012-01-01

    A document discusses a liquid crystal variable retarder, an electro-optic element that changes the polarization of an optical beam in response to a low-voltage electronic signal. This device can be fabricated so that the element creates, among other states, a half-wave of retardance that can be reduced to a very small retardance. When aligned to a polarized source, this can act to rotate the polarization by 90 in one state, but generate no rotation in the other state. If the beam is then incident on a polarization beam splitter, it will efficiently switch from one path to the other when the voltage is applied. The laser beam switching system has no moving parts, improving reliability over mechanical switching. It is low cost, tolerant of high laser power density, and needs only simple drive electronics, minimizing the required system resources.

  15. Minimizing the Switch and Link Conflicts in an Optical Multi-stage Interconnection Network

    Directory of Open Access Journals (Sweden)

    Ved Prakash Bhardwaj

    2011-07-01

    Full Text Available Multistage Interconnection Networks (MINs are very popular in switching and communication applications. A MIN connects N inputs to N outputs and is referred as an N andamp;times; N MIN; having size N. Optical Multistage Interconnection Network (OMIN represents an important class of Interconnection networks. Crosstalk is the basic problem of OMIN. Switch Conflict and Link Conflict are the two main reason of crosstalk. In this paper, we are considering both problems. A number of techniques like Optical window, Improved Window, Heuristic, Genetic, and Zero have been proposed earlier in this research domain. In this paper, we have proposed two algorithms called Address Selection Algorithm and Route Selection Algorithm (RSA. RSA is based on Improved Window Method. We have applied the proposed algorithms on existing Omega network, having shuffleexchange connection pattern. The main functionality of ASA and RSA is to minimize the number of switch and link conflicts in the network and to provide conflict free routes.

  16. Contentionless transmission in buffer-less slotted optical packet switched networks

    Science.gov (United States)

    Asghari, Masoud; Ghaffarpour Rahbar, Akbar

    2016-07-01

    Contention of optical packets in optical packet switched (OPS) networks is a major problem, and it is even more critical in buffer-less OPS networks. In this paper, an innovative contention avoidance technique is proposed which uses combination of special traffic shaping at ingress switches and special time slot reservation technique through the path of traffic flows in core network. This novel protocol is called contentionless transmission OPS (CLTOPS) suitable for buffer-less slotted OPS networks. Performance evaluations show that the CLTOPS can outperform the original slotted-OPS architecture in terms of packet loss rate (PLR) performance, with or without using wavelength conversion. It is shown that there is a trade-off between the amount of improvement in PLR and additional delay applied to the users' packets at the ingress switches buffers. However, appropriate parameters can be selected to make the additional delay tolerable for users' applications.

  17. Reversible, electrical and optical switching on silver 3-phenyl-1-ureidonitrile complex thin films

    Institute of Scientific and Technical Information of China (English)

    张昊旭; 时东霞; 宋延林; 刘虹雯; 侯士敏; 薛增泉; 高鸿钧

    2002-01-01

    We report on the reversible, electrical and optical switching on silver 3-phenyl-l-ureidonitrile complex thin films.The films can switch from a high impedance state to a low impedance state with an applied electric field at the thresholdof 3.5 × 107V/m. Furthermore, the films can be switched back to the original state by treating the samples at about80℃. The optical recording is fulfilled using a semiconductor laser with a wavelength of 780nm. Erasure can beaccomplished by bulk heating or by the laser working with the power beneath the threshold. No loss of the organic wasfound in the experiments. This material may have a potential application in ultrahigh data density storage.

  18. Preparation, optical properties and 1 Multiplication-Sign 2 polymeric thermo-optic switch of polyurethane-urea

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Fengxian, E-mail: fxqiuchem@163.com [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Cao, Zhijuan [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Cao, Guorong; Guan, Yijun; Shen, Qiang [Department of Physics, Jiangsu University, Zhenjiang 212013 (China); Wang, Qing; Yang, Dongya [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China)

    2012-08-15

    A polyurethane-urea (PUU) containing azo chromophore, polyether polyol (NJ-220) and isophorone diisocyanate (IPDI) was prepared. The structure, thermal property and mechanical properties of obtained PUU were characterized and measured by the UV-visible spectroscopy, Fourier transform infrared, Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The refractive index (n) of PUU was determined at different temperature and wavelength (532 nm, 650 nm and 850 nm) using attenuated total reflection (ATR) technique, and the thermo-optic coefficients (dn/dT) were -5.3643 Multiplication-Sign 10{sup -4} Degree-Sign C{sup -1}, -5.2500 Multiplication-Sign 10{sup -4} Degree-Sign C{sup -1} and -4.6071 Multiplication-Sign 10{sup -4} Degree-Sign C{sup -1}, respectively. Using the Charge Coupled Device (CCD) digital imaging devices, transmission loss of PUU was measured and the value was 0.659 dB cm{sup -1}. A 1 Multiplication-Sign 2 polymeric thermo-optic switch based on the thermo-optic effect of PUU film was proposed. With branching angle of 0.143 Degree-Sign and the finite difference beam propagation method (FD-BPM), the polymeric thermo-optic switch was simulated. The result showed that the power consumption of the thermo-optic switch could be only 0.72 mW, and the response time of the switch was about 3.0 ms. The obtained PUU has a significant improvement in reducing the power consumption and response time compared with those of the normal polymeric thermo-optic switches. -- Highlights: Black-Right-Pointing-Pointer Preparation and structural characterization of a novel azo polyurethane-urea (PUU). Black-Right-Pointing-Pointer The mechanical performance and thermal property of PUU film. Black-Right-Pointing-Pointer The thermo-optic property, transmission loss and dispersion property of PUU. Black-Right-Pointing-Pointer Proposed a new 1 Multiplication-Sign 2 polymeric thermo-optic switch.

  19. All-optical integrated Mach-Zehnder switching in lithium niobate waveguides due to cascaded nonlinearities

    NARCIS (Netherlands)

    Baek, Y.; Schiek, R.; Krijnen, G.J.M.; Stegeman, G.I.; Baumann, I.; Sohler, W.

    1996-01-01

    In all-optical switching the required phase shift is produced by the light itself. Typically this shift has been achieved via the intensity-dependent refractive index. But recently the fact that the so-called cascaded second-order nonlinearity can imitate the third-order nonlinearity was proven expe

  20. Feasibility of Optical Packet Switched WDM Networks without Packet Synchronisation Under Bursty Traffic Conditions

    DEFF Research Database (Denmark)

    Fjelde, Tina; Hansen, Peter Bukhave; Kloch, Allan;

    1999-01-01

    We show that complex packet synchronisation may be avoided in optical packetswitched networks. Detailed traffic analysis demonstrates that packet lossratios of 1e-10 are feasible under bursty traffic conditions for a highcapacity network consisting of asynchronously operated add-drop switch...

  1. Design and Fabrication of Micromechanical Optical Switches Based on the Low Applied Voltage

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A micromechanical optical switch driven by electrostatic was fabricated with (100) silicon and tilted 2.5° (111) silicon. The pull-in voltage is 13.2V, the insertion loss is less than 1.4dB, the crosstalk is less than -50 dB.

  2. Energy-bandwidth trade-off in all-optical photonic crystal microcavity switches

    DEFF Research Database (Denmark)

    Heuck, Mikkel; Kristensen, Philip Trøst; Mørk, Jesper

    2011-01-01

    . As a specific example of a switching application, we investigate the demultiplexing of an optical time division multiplexed signal. To quantify the energy-bandwidth trade-off, we introduce a figure of merit for the detection of the demultiplexed signal. In such investigations it is crucial to consider...

  3. All-fiber hybrid photon-plasmon circuits: integrating nanowire plasmonics with fiber optics.

    Science.gov (United States)

    Li, Xiyuan; Li, Wei; Guo, Xin; Lou, Jingyi; Tong, Limin

    2013-07-01

    We demonstrate all-fiber hybrid photon-plasmon circuits by integrating Ag nanowires with optical fibers. Relying on near-field coupling, we realize a photon-to-plasmon conversion efficiency up to 92% in a fiber-based nanowire plasmonic probe. Around optical communication band, we assemble an all-fiber resonator and a Mach-Zehnder interferometer (MZI) with Q-factor of 6 × 10(6) and extinction ratio up to 30 dB, respectively. Using the MZI, we demonstrate fiber-compatible plasmonic sensing with high sensitivity and low optical power.

  4. Capacitively Coupled CMOS VCSEL Driver Circuits for Optical Communication

    Science.gov (United States)

    Kozlov, Victor

    This thesis presents the analysis, design and implementation of a common-cathode capacitively-coupled VCSEL driver in 65nm CMOS intended for short-reach optical interconnects. The driver consists of an AC-coupled high-frequency path and a low-frequency path that provides DC signal components. By increasing the low-frequency path bandwidth by 10 times compared to previous AC-coupled drivers allowed the on-chip coupling capacitor to be reduced to 2.1pF, occupying 3 times less area than prior art. The driver introduces capacitively-coupled two-tap emphasis to equalize the VCSEL's optical response. The VCSEL was modulated with an OMA of up to 5.1dBm and an ER of 9dB, measuring an RMS jitter of 5ps at a data rate of 15Gb/s, which represents the highest OMA and ER achieved in high-speed anode-driving LDDs. The driver could be programmed for a low-power mode, outputting 2.3dBm OMA at power consumption of only 30mW, corresponding to an energy efficiency of 2pJ/bit.

  5. Performance of electronic switching circuits based on bipolar power transistors at low temperature

    Science.gov (United States)

    El-Ghanam, S. M.; Abdel Basit, W.

    2011-03-01

    In this paper, the performance of the bipolar power transistor of the type MJE13007 was evaluated under very low temperature levels. The investigation was carried out to establish a baseline on functionality and to determine suitability of this device for use in space applications under cryogenic temperatures. The static and dynamic electrical characteristics of the proposed transistor were studied at low temperature levels ranging from room level (300 K) down to 100 K. From which, it is clear that, several electrical parameters were affected due to operation on such very low temperature range, e.g. the threshold voltage ( V γ) increasing from 0.62 up to 1.05 V; while the current gain h FE decreases significantly from 26 down to 0.54. Also, the capacitance-voltage relationships ( C- V) of the collector-base and emitter-base junctions were studied at cryogenic temperatures, where a pronounced decrease was observed in the capacitances value due to temperature decrease. For example, at F = 50 kHz; CCB and CBE decreased from 2.33 nF down to 0.07 nF and from 36.2 down to 12 nF, respectively due to decreasing of temperature level from 300 down to 100 K. Finally the study was extended to include the dynamic characteristics and switching properties of the tested high power transistor. The dependency of both the rise and fall times ( t r, t f) on the temperature shows great variations with temperature.

  6. Analysis of Fault Arc in High-Speed Switch Applied in Hybrid Circuit Breaker

    Science.gov (United States)

    Wu, Yifei; Ren, Zhigang; Feng, Ying; Li, Mei; Zhang, Hantian

    2016-03-01

    The behavior of fault arc in a high-speed switch (HSS) has been studied theoretically and experimentally. A simplified HSS setup is designed to support this work. A two-dimensional arc model is developed to analyze the characteristics of fault arc based on magnetic-hydrodynamic (MHD) theory. The advantage of such a model is that the thermal transfer coefficient can be determined by depending on the numerical method alone. The influence of net emission coefficients (NEC) radiation model and P1 model on fault arc is analyzed in detail. Results show that NEC model predicts more radiation energy and less pressure rise without the re-absorption effect considered. As a consequence, P1 model is more suitable to calculate the pressure rise caused by fault arc. Finally, the pressure rise during longer arcing time for different arc currents is predicted. supported by National Key Basic Research Program of China (973 Program) (No. 2015CB251001), National Natural Science Foundation of China (Nos. 51221005, 51177124, 51377128, 51323012), the Science and Technology Project Funds of the Grid State Corporation SGSNKYOOKJJS1501564 and Shaanxi Province Natural Science Foundation of China (No. 2013JM-7010)

  7. On the data rate extension of semiconductor optical amplifier-based ultrafast nonlinear interferometer in dual rail switching mode using a cascaded optical delay interferometer

    Science.gov (United States)

    Zoiros, K. E.; Demertzis, C.

    2011-10-01

    The feasibility of increasing by a factor of two the data speed of the semiconductor optical amplifier (SOA)-based ultrafast nonlinear interferometer in dual rail switching mode by means of a cascaded optical delay interferometer (ODI) is explored and shown through numerical simulation. From the theoretical analysis it has been found that such extension cannot be done without employing this passive element for any selection of the critical parameters but the SOA carrier lifetime, for which the requirements are yet very demanding. If, however, the time delay introduced by the ODI is adjusted to almost 1/3rd of the bit period, then the result of Boolean XOR operation can be improved for a specified range of parameter values, which can be further selected to be more relaxed than is possible when the ODI is not being used. The use of the ODI allows both error-free and pattern-free performance at the output of the interferometric structure configured as ultrafast XOR gate. In this manner the scheme can offer a practical alternative solution for extending the operating rate of this logical module and enabling its exploitation as a basic building unit in more sophisticated all-optical circuits and subsystems.

  8. Toehold-mediated nonenzymatic amplification circuit on graphene oxide fluorescence switching platform for sensitive and homogeneous microRNA detection

    International Nuclear Information System (INIS)

    A novel graphene oxide (GO) fluorescence switch-based homogenous system has been developed to solve two problems that are commonly encountered in conventional GO-based biosensors. First, with the assistance of toehold-mediated nonenzymatic amplification (TMNA), the sensitivity of this system greatly surpasses that of previously described GO-based biosensors, which are always limited to the nM range due to the lack of efficient signal amplification. Second, without enzymatic participation in amplification, the unreliability of detection resulting from nonspecific desorption of DNA probes on the GO surface by enzymatic protein can be avoided. Moreover, the interaction mechanism of the double-stranded TMNA products contains several single-stranded toeholds at two ends and GO has also been explored with combinations of atomic force microscopy imaging, zeta potential detection, and fluorescence assays. It has been shown that the hybrids can be anchored to the surface of GO through the end with more unpaired bases, and that the other end, which has weaker interaction with GO, can escape GO adsorption due to the robustness of the central dsDNA structures. We verified this GO fluorescence switch-based detection system by detecting microRNA 21, an overexpressed non-encoding gene in a variety of malignant cells. Rational design of the probes allowed the isothermal nonenzymatic reaction to achieve more than 100-fold amplification efficiency. The detection results showed that our strategy has a detection limit of 10 pM and a detection range of four orders of magnitude. - Highlights: • This paper explored the interaction mechanism of TMNA products with GO surface. • This homogeneous and isothermal system permits a detection limit of 10 pM for microRNA. • This nonenzymatic strategy can avoid nonspecific desorption caused by enzyme protein. • The interaction model can be used to explore the application ability of nonenzymatic circuit

  9. Toehold-mediated nonenzymatic amplification circuit on graphene oxide fluorescence switching platform for sensitive and homogeneous microRNA detection

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ru; Liao, Yuhui; Zhou, Xiaoming, E-mail: zhouxm@scnu.edu.cn; Xing, Da, E-mail: xingda@scnu.edu.cn

    2015-08-12

    A novel graphene oxide (GO) fluorescence switch-based homogenous system has been developed to solve two problems that are commonly encountered in conventional GO-based biosensors. First, with the assistance of toehold-mediated nonenzymatic amplification (TMNA), the sensitivity of this system greatly surpasses that of previously described GO-based biosensors, which are always limited to the nM range due to the lack of efficient signal amplification. Second, without enzymatic participation in amplification, the unreliability of detection resulting from nonspecific desorption of DNA probes on the GO surface by enzymatic protein can be avoided. Moreover, the interaction mechanism of the double-stranded TMNA products contains several single-stranded toeholds at two ends and GO has also been explored with combinations of atomic force microscopy imaging, zeta potential detection, and fluorescence assays. It has been shown that the hybrids can be anchored to the surface of GO through the end with more unpaired bases, and that the other end, which has weaker interaction with GO, can escape GO adsorption due to the robustness of the central dsDNA structures. We verified this GO fluorescence switch-based detection system by detecting microRNA 21, an overexpressed non-encoding gene in a variety of malignant cells. Rational design of the probes allowed the isothermal nonenzymatic reaction to achieve more than 100-fold amplification efficiency. The detection results showed that our strategy has a detection limit of 10 pM and a detection range of four orders of magnitude. - Highlights: • This paper explored the interaction mechanism of TMNA products with GO surface. • This homogeneous and isothermal system permits a detection limit of 10 pM for microRNA. • This nonenzymatic strategy can avoid nonspecific desorption caused by enzyme protein. • The interaction model can be used to explore the application ability of nonenzymatic circuit.

  10. Global Electric Circuit Diurnal Variation Derived from Storm Overflight and Satellite Optical Lightning Datasets

    Science.gov (United States)

    Mach, Douglas M.; Blakeslee, R. J.; Bateman, M. J.; Bailey, J. C.

    2011-01-01

    We have combined analyses of over 1000 high altitude aircraft observations of electrified clouds with diurnal lightning statistics from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) to produce an estimate of the diurnal variation in the global electric circuit. Using basic assumptions about the mean storm currents as a function of flash rate and location, and the global electric circuit, our estimate of the current in the global electric circuit matches the Carnegie curve diurnal variation to within 4% for all but two short periods of time. The agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Mean contributions to the global electric circuit from land and ocean thunderstorms are 1.1 kA (land) and 0.7 kA (ocean). Contributions to the global electric circuit from ESCs are 0.22 kA for ocean storms and 0.04 kA for land storms. Using our analysis, the mean total conduction current for the global electric circuit is 2.0 kA.

  11. Packetisation in Optical Packet Switch Fabrics using adaptive timeout values

    DEFF Research Database (Denmark)

    Mortensen, Brian Bach

    2006-01-01

    either because the timer reaches a specific timeout value, or because the optical packet is completely filled with segments. Only two distinct values of the timeout value are used. Which of the two timeout values to use, is selected by 3 different control thresholds. The first threshold level applies to...... the inter arrival rate at the individual VOQs. The remaining thresholds applies to the optical slot level inter arrival rate at the input and output line cards. If any measurements are beyond a given threshold, the higher timeout value is used. The proposed method can be used to make a trade...

  12. 开关电源的过载保护电路设计%Design of Over Load Protection Circuit for Switching Mode Power Supply

    Institute of Scientific and Technical Information of China (English)

    刘雪山; 杨静; 张鸿儒

    2009-01-01

    基于UC3842的反激式开关电源,文中从原理和实验两方面分析了恒功率控制和恒电流控制的过载保护电路,阐述了各自的特点,并提出了一种适用于短暂过载场合的延时锁定关断过载保护电路,实验证明此电路工作于保护模式时开关元件无开关应力,为高峰值负载电源过载保护电路的设计提供了一种有效的方法.%Based on fly-hack converter with UC3842 controlled, overload protection circuits of constant power control and constant current control are analyzed from principle and experiment result. The characteristics of these two overload protection circuits are presented. A kind of timer latch protection circuit used for transient overload is proposed. Experi-ment results verify that switching components do not have switching stress in protection mode, which provides an effective method to design protection circuit for switching mode power supply with high peak load.

  13. Space radiation effect on fibre optical gyroscope control circuit and compensation algorithm

    Institute of Scientific and Technical Information of China (English)

    Zhang Chun-Xi; Tian Hai-Ting; Li Min; Jin Jing; Song Ning-Fang

    2008-01-01

    The process of a γ-irradiation experiment of fibre optical gyroscope (FOG) control circuit was described,in which it is demonstrated that the FOG control circuit,except for D/A converter,could endure the dose of 10krad with the protection of cabin material.The distortion and drift in D/A converter due to radiation,which affect the performance of FOG seriously,was indicated based on the elemental analysis.Finally,a compensation network based on adaptive neuro-fuzzy inference system is proposed and its function is verified by simulation.

  14. Research and Design of Monolithic Decision Circuit for Optical Communication System①②

    Institute of Scientific and Technical Information of China (English)

    ZHANGYaqi; ZHAOJie

    1997-01-01

    In this paper,the cause of bit-error is analyzed when data are decided in the optical receiver.A monolithic D-ff decision circuit is designed.It can work effectively at 622 Mb/s.Moreover,a decision method of parallel processing to improve thd decision speed is presented,through which the parallel circuit can work up to 1 Gb/s using the same model.With the technique,higher-speed data can be decided by using lower speed device.

  15. Design and Performance Evaluation of Optical Ethernet Switching Architecture with Liquid Crystal on Silicon-Based Beam-Steering Technology

    Science.gov (United States)

    Cheng, Yuh-Jiuh; Chou, H.-H.; Shiau, Yhi; Cheng, Shu-Ying

    2016-07-01

    A non-blocking optical Ethernet switching architecture with liquid crystal on a silicon-based beam-steering switch and optical output buffer strategies are proposed. For preserving service packet sequencing and fairness of routing sequence, priority and round-robin algorithms are adopted at the optical output buffer in this research. Four methods were used to implement tunable fiber delay modules for the optical output buffers to handle Ethernet packets with variable bit-rates. The results reported are based on the simulations performed to evaluate the proposed switching architecture with traffic analysis under a traffic model captured from a real-core network.

  16. VO{sub 2}-like thermo-optical switching effect in one-dimensional nonlinear defective photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Juan, E-mail: juanzhang@staff.shu.edu.cn, E-mail: ywang@siom.ac.cn; Zhang, Rongjun [Key Laboratory of Specialty Fiber Optics and Optical Access Networks, School of Communication and Information Engineering, Shanghai University, Shanghai 200072 (China); Wang, Yang, E-mail: juanzhang@staff.shu.edu.cn, E-mail: ywang@siom.ac.cn [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2015-06-07

    A new approach to achieve VO{sub 2}-like thermo-optical switching in a one-dimensional photonic crystal by the combination of thermo-optical and optical Kerr effects was proposed and numerically demonstrated in this study. The switching temperature and the hysteresis width can be tuned in a wide temperature range. Steep transition, high optical contrast, and low pumping power can be achieved at the same time. This kind of one-dimensional photonic crystal-based bistable switch will be low-cost, easy-to-fabricate, and versatile in practical applications compared with traditional VO{sub 2}-type one.

  17. Switching Arithmetic for DC to DC Converters Using Delta Sigma Modulator Based Control Circuit

    Directory of Open Access Journals (Sweden)

    K.Diwakar

    2016-02-01

    Full Text Available In the proposed arithmetic unit for dc to dc converters using delta sigma modulator, a new technique is proposed for addition and multiplication of sampled analog signals. The output is in digital form to drive the converters. The conventional method has input signal limitation whereas in the proposed method the inputs can vary to full-scale. The addition of two discrete signals is done by sampling the two signals at a period called update period and feeding each signal to the input of signal dependant delta sigma modulator for half of the update period and combining the outputs for the update period. The extension of three discrete data addition can be carried out by using the same technique. For the multiplication of two discrete signals different method is adopted. One analog signal is fed to the input of first delta-sigma modulator (DSM1 after sampling. The sampled output of the second analog signal is negated or not negated depending on the bit state at the output of DSM1 and is fed to the input of second DSM(DSM2. The resulting bit stream at the output of DSM2 is the digital representation of the product of the sampled data of the two analog signals. In order to multiply three discrete data, the sampled output of third data is negated or not negated depending on the bit state at the output of DSM2 and is fed to the input of third DSM(DSM3. The resulting bit stream at the output of DSM3 is the digital representation of the product of the sampled data of the three analog signals. Using the proposed adder and multiplier circuits any expressions can be evaluated such that the average value of the digital output of the arithmetic unit over the update period gives the value of expressions during that period. The digital output of the arithmetic unit is used to drive the dc-dc converters.

  18. Design and implementation of ROADM based on fiber Bragg grating and optical switch

    Science.gov (United States)

    Zheng, Liming; Zeng, Simin; Wang, Faqiang

    2007-11-01

    With the development of optical communication technology, all-optical network is promising in next generation networks. Characterized by good transparency, wavelength routing, compatibility and scalability, all-optical network has become the most promising candidate for future high-capacity network. And reconfigurable optical add/drop multiplexer (ROADM) has been regarded as one of the key equipments of the intelligent WDM optical communication network. In this paper, we compare several design methods of ROADM, and introduce the design and implementation of ROADM based on fiber Bragg grating (FBG) and optical switch (OSW). We also propose the new idea of FBGs OSW composed OSW and FBG collimator, which is the integration package of FBGs and collimator. Benefited from the filter characteristics of FBGs and the selectivity of OSW, the performance of ROADM can be optimized. In addition, the ROADM has been tested and analyzed.

  19. Modelling a nonlinear optical switching in a standard photonic crystal fiber infiltrated with carbon disulfide

    Science.gov (United States)

    Munera, Natalia; Acuna Herrera, Rodrigo

    2016-06-01

    In this letter, a numerical analysis is developed for the propagation of ultrafast optical pulses through a standard photonic crystal fiber (PCF) consisting of two infiltrated holes using carbon disulfide (CS2). This material is a good choice since it has highly nonlinear properties, what makes it a good candidate for optical switching and broadband source at low power compared to traditional nonlinear fiber coupler. Based on supermodes theory, a set of generalized nonlinear equations is presented in order to study the propagation characteristics. It is shown in this letter that it is possible to get optical switching behavior at low power and how the dispersion, as well as, the two infiltrated holes separation influence this effect. Finally, we see that supercontinuum generation can be induced equally in both infiltrated holes despite no initial excitation at one hole.

  20. Reversible optical switching of highly confined phonon-polaritons with an ultrathin phase-change material

    Science.gov (United States)

    Li, Peining; Yang, Xiaosheng; Maß, Tobias W. W.; Hanss, Julian; Lewin, Martin; Michel, Ann-Katrin U.; Wuttig, Matthias; Taubner, Thomas

    2016-08-01

    Surface phonon-polaritons (SPhPs), collective excitations of photons coupled with phonons in polar crystals, enable strong light-matter interaction and numerous infrared nanophotonic applications. However, as the lattice vibrations are determined by the crystal structure, the dynamical control of SPhPs remains challenging. Here, we realize the all-optical, non-volatile, and reversible switching of SPhPs by controlling the structural phase of a phase-change material (PCM) employed as a switchable dielectric environment. We experimentally demonstrate optical switching of an ultrathin PCM film (down to 7 nm, 70k0, k0 = 2π/λ) in quartz. Our proof of concept allows the preparation of all-dielectric, rewritable SPhP resonators without the need for complex fabrication methods. With optimized materials and parallelized optical addressing we foresee application potential for switchable infrared nanophotonic elements, for example, imaging elements such as superlenses and hyperlenses, as well as reconfigurable metasurfaces and sensors.

  1. Performance evaluation of 10GBASE optical transceivers for Cisco 10-gigabit Ethernet switching architecture

    Science.gov (United States)

    Zhang, Xiaojing; Cain, Jeff C.

    2002-09-01

    This paper presents the process and methodology employed to perform evaluation and analyses for the optical interface that delivers and receives 10Gb/s Ethernet traffic on Cisco's industrial leading switching architecture. Especially, we examined in detail the optical properties for commercially available 10GBASE-LR transceiver modules, with respect to IEEE 802.3ae specifications. The sampled results under room temperature are listed for comparison. Eye diagrams were recorded as a function of transmission distance, as well as temperature variation. System stability issues are also studied following a brief introduction to Cisco standard ODVT (Optical Design Verification Test) procedure.

  2. Burst switched optical networks supporting legacy and future service types

    DEFF Research Database (Denmark)

    Franzl, Gerald; Hayat, Faisal; Holynski, Tomasz;

    2011-01-01

    Focusing on the principles and the paradigm of OBS an overview addressing expectable performance and application issues is presented. Proposals on OBS were published over a decade and the presented techniques spread into many directions. The paper comprises discussions of several challenges that ...... and found capable to overcome shortcomings of recent proposals. In conclusion, an OBS that offers different connection types may support most client demands within a sole optical network layer....

  3. Dopamine-mediated learning and switching in cortico-striatal circuit explain behavioral changes in reinforcement learning.

    Directory of Open Access Journals (Sweden)

    Simon eHong

    2011-03-01

    Full Text Available The basal ganglia (BG are thought to play a crucial role in reinforcement learning. Central to the learning mechanism are dopamine D1 and D2 receptors located in the cortico-striatal synapses. However, it is still unclear how this dopamine-mediated synaptic plasticity is deployed and coordinated during reward-contingent behavioral changes. Here we propose a computational model of reinforcement learning that uses different thresholds of D1- and D2-mediated synaptic plasticity which are antagonized by dopamine-independent synaptic plasticity. A phasic increase in dopamine release caused by a larger-than-expected reward induces long-term potentiation (LTP in the direct pathway, whereas a phasic decrease in dopamine release caused by a smaller-than-expected reward induces a cessation of long-term depression (LTD, leading to LTP in the indirect pathway. This learning mechanism can explain the robust behavioral adaptation observed in a location-reward-value-association task where the animal makes shorter latency saccades to rewarding locations. The changes in saccade latency become quicker as the monkey becomes more experienced. This behavior can be explained by a switching mechanism which activates the cortico-striatal circuit selectively. Our model can also simulate the effects of D1 and D2 receptor blockade, and behavioral changes in Parkinson’s disease.

  4. Optical switching and detection of 640 Gbits/s optical time-division multiplexed data packets transmitted over 50 km of fiber

    DEFF Research Database (Denmark)

    Gomez-Agis, F.; Hu, Hao; Luo, J.;

    2011-01-01

    We demonstrate 1 × 4 optical-packet switching with error-free transmission of 640 Gbits/s single-wavelength optical time-division multiplexed data packets including clock distribution and short pulse generation for optical time demultiplexing based on a cavityless pulse source. © 2011 Optical...

  5. Experimental investigation of a four-qubit linear-optical quantum logic circuit.

    Science.gov (United States)

    Stárek, R; Mičuda, M; Miková, M; Straka, I; Dušek, M; Ježek, M; Fiurášek, J

    2016-01-01

    We experimentally demonstrate and characterize a four-qubit linear-optical quantum logic circuit. Our robust and versatile scheme exploits encoding of two qubits into polarization and path degrees of single photons and involves two crossed inherently stable interferometers. This approach allows us to design a complex quantum logic circuit that combines a genuine four-qubit C(3)Z gate and several two-qubit and single-qubit gates. The C(3)Z gate introduces a sign flip if and only if all four qubits are in the computational state |1〉. We verify high-fidelity performance of this central four-qubit gate using Hofmann bounds on quantum gate fidelity and Monte Carlo fidelity sampling. We also experimentally demonstrate that the quantum logic circuit can generate genuine multipartite entanglement and we certify the entanglement with the use of suitably tailored entanglement witnesses. PMID:27647176

  6. Information Model for Connection Management in Automatic Switched Optical Network

    Institute of Scientific and Technical Information of China (English)

    Xu Yunbin(徐云斌); Song Hongsheng; Gui Xuan; Zhang Jie; Gu Wanyi

    2004-01-01

    The three types of connections (Permanent Connection, Soft Permanent Connection and Switched Connection) provided by ASON can adapt the requirement of different network services. Management and maintenance of these three connections are the most important aspect of ASON management. The information models proposed in this paper are used for the purpose of ASON connection management. Firstly a new information model is proposed to meet the requirement for the control plane introduced by ASON. In this model, a new class ControlNE is given, and the relationship between the ControlNE and the transport NE (network element) is also defined. Then this paper proposes information models for the three types of connections for the first time, and analyzes the relationship between the three kinds of connections and the basic network transport entities. Finally, the paper defines some CORBA interfaces for the management of the three connections. In these interfaces, some operations such as create or release a connection are defined, and some other operations can manage the performance of the three kinds of connections, which is necessary for a distributed management system.

  7. All-metallic electrically gated 2H-TaSe2 thin-film switches and logic circuits

    International Nuclear Information System (INIS)

    We report the fabrication and performance of all-metallic three-terminal devices with tantalum diselenide thin-film conducting channels. For this proof-of-concept demonstration, the layers of 2H-TaSe2 were exfoliated mechanically from single crystals grown by the chemical vapor transport method. Devices with nanometer-scale thicknesses exhibit strongly non-linear current-voltage characteristics, unusual optical response, and electrical gating at room temperature. We have found that the drain-source current in thin-film 2H-TaSe2–Ti/Au devices reproducibly shows an abrupt transition from a highly resistive to a conductive state, with the threshold tunable via the gate voltage. Such current-voltage characteristics can be used, in principle, for implementing radiation-hard all-metallic logic circuits. These results may open new application space for thin films of van der Waals materials

  8. Electro-optic switching in phase-discontinuity complementary metasurface twisted nematic cell.

    Science.gov (United States)

    Lee, Y U; Kim, J; Woo, J H; Bang, L H; Choi, E Y; Kim, E S; Wu, J W

    2014-08-25

    Electro-optic switching of refraction is experimentally demonstrated in a phase-discontinuity complementary metasurface twisted nematic cell. The phase-discontinuity complementary metasurface is fabricated by focused-ion-beam milling, and a twisted nematic cell is constructed with complementary V-shape slot antenna metasurface. By application of an external voltage, switching is achieved between ordinary refraction and extraordinary refraction satisfying the generalized Snell's law. It has a strong implication for applications in spatial light modulation and wavelength division multiplexer/demultiplexer in a near-IR spectral range. PMID:25321285

  9. Multi-hop optical label switching with coherent detected spectral amplitude code labels

    Science.gov (United States)

    Cao, Yongsheng

    Based on label stacking principles and coherent detection, we present a two-hop, coherent detected spectral amplitude code (SAC) labeled system to accomplish ultrafast packet forwarding for packet-switched metropolitan area networks. An optical switching network with two forwarding nodes, two 156 Mb/s SAC labels, and 40 Gb/s differential quadrature phase shift keying (DQPSK) payloads is demonstrated by computer simulation. The bit error rate (BER) performances of coherent detected SAC labels and high speed payload over 160 km fiber after two hops transmission are accessed, respectively.

  10. Syudy of Token Generation for Burst Traffic Shaping in Optical Burst Switching Networks

    Institute of Scientific and Technical Information of China (English)

    Tang Wan; So Won-ho; Lu Ji-guang; Kim Young-chon

    2004-01-01

    Traffic shaping is one of important control operation to guarantee the Quality of Service (QoS) in optical burst switching (OBS) networks. The efficiency of traffic shaping is mainly determined by token generation method. In this paper, token generation methods of traffic shaping are evaluated by using three kinds of probability distribution, and are analyzed in terms of burst blocking probability, throughput and correlation by simulation. The simulation results show that the token generation methods decrease the burst correlation of Label Switched Paths (LSPs), and solve traffic congestion as well. The different burst arrival processes have small impact on the blocking probability for OBS networks.

  11. Electro-optical switch based on continuous metasurface embedded in Si substrate

    Directory of Open Access Journals (Sweden)

    Yali Sun

    2015-11-01

    Full Text Available Switchable metasurfaces with fast responses and high efficiency are highly desirable in various applications. In this paper, we propose and analyze a novel electro-optical switch based on continuous metasurface embedded in Si substrate. The simulative results indicate that the embedded and continuous metasurface structure is able to increase the interaction volume between the metal antennas and the surrounding substrate, hence enhances the tuning effect when changing the refractive index of Si by an injection current, resulting in fully switching between anomalous and normal reflections, and achieving a high extinction ratio even under a smaller refractive index variation.

  12. Reduction of nonlinear patterning effects in SOA-based All-optical Switches using Optical filtering

    DEFF Research Database (Denmark)

    Nielsen, Mads Lønstrup; Mørk, Jesper; Skaguchi, J.;

    2005-01-01

    We explain theoretically, and demonstrate and quantify experimentally, how appropriate filtering can reduce the dominant nonlinear patterning effect, which limits the performance of differential-mode SOA-based switches.......We explain theoretically, and demonstrate and quantify experimentally, how appropriate filtering can reduce the dominant nonlinear patterning effect, which limits the performance of differential-mode SOA-based switches....

  13. Localization and Imaging of Integrated Circuit Defect Using Simple Optical Feedback Detection

    Directory of Open Access Journals (Sweden)

    Vernon Julius Cemine

    2004-12-01

    Full Text Available High-contrast microscopy of semiconductor and metal edifices in integrated circuits is demonstrated by combining laser-scanning confocal reflectance microscopy, one-photon optical-beam-induced current (1P-OBIC imaging, and optical feedback detection via a commercially available semiconductor laser that also serves as the excitation source. The confocal microscope has a compact in-line arrangement with no external photodetector. Confocal and 1P-OBIC images are obtained simultaneously from the same focused beam that is scanned across the sample plane. Image pairs are processed to generate exclusive high-contrast distributions of the semiconductor, metal, and dielectric sites in a GaAs photodiode array sample. The method is then utilized to demonstrate defect localization and imaging in an integrated circuit.

  14. 1×4 Optical packet switching of variable length 640 Gbit/s data packets using in-band optical notch-filter labeling

    DEFF Research Database (Denmark)

    Medhin, Ashenafi Kiros; Kamchevska, Valerija; Galili, Michael;

    2014-01-01

    We experimentally perform 1×4 optical packet switching of variable length 640 Gbit/s OTDM data packets using in-band notch-filter labeling with only 2.7-dB penalty. Up to 8 notches are employed to demonstrate scalability of the labeling scheme to 1×256 switching operation.......We experimentally perform 1×4 optical packet switching of variable length 640 Gbit/s OTDM data packets using in-band notch-filter labeling with only 2.7-dB penalty. Up to 8 notches are employed to demonstrate scalability of the labeling scheme to 1×256 switching operation....

  15. Digital measuring scheme for half-wave voltage of Y-tap multiple integrated optical circuit

    Institute of Scientific and Technical Information of China (English)

    Yuanhong Yang(杨远洪); Hongtao Yu(于洪涛)

    2004-01-01

    A high-precision digital measuring scheme for half-wave voltage of Y-tap multiple integrated optical circuits is proposed. This scheme is based on Sagnac interferometer modulated with digital step waveform whose frequency is half of eigen frequency of the interferometer. The technology and measuring precision are discussed. An experimental setup is made and the temperature-dependences of half-wave voltage of two samples are studied. Analysis and experimental study prove that this scheme is convenient and accurate.

  16. High-contrast fluorescence imaging in fixed and living cells using optimized optical switches.

    Directory of Open Access Journals (Sweden)

    Liangxing Wu

    Full Text Available We present the design, synthesis and characterization of new functionalized fluorescent optical switches for rapid, all-visible light-mediated manipulation of fluorescence signals from labelled structures within living cells, and as probes for high-contrast optical lock-in detection (OLID imaging microscopy. A triazole-substituted BIPS (TzBIPS is identified from a rational synthetic design strategy that undergoes robust, rapid and reversible, visible light-driven transitions between a colorless spiro- (SP and a far-red absorbing merocyanine (MC state within living cells. The excited MC-state of TzBIPS may also decay to the MC-ground state emitting near infra-red fluorescence, which is used as a sensitive and quantitative read-out of the state of the optical switch in living cells. The SP to MC transition for a membrane-targeted TzBIPS probe (C₁₂-TzBIPS is triggered at 405 nm at an energy level compatible with studies in living cells, while the action spectrum of the reverse transition (MC to SP has a maximum at 650 nm. The SP to MC transition is complete within the 790 ns pixel dwell time of the confocal microscope, while a single cycle of optical switching between the SP and MC states in a region of interest is complete within 8 ms (125 Hz within living cells, the fastest rate attained for any optical switch probe in a biological sample. This property can be exploited for real-time correction of background signals in living cells. A reactive form of TzBIPS is linked to secondary antibodies and used, in conjunction with an enhanced scope-based analysis of the modulated MC-fluorescence in immuno-stained cells, for high-contrast immunofluorescence microscopic analysis of the actin cytoskeleton.

  17. Contention avoidance using dual-fuzzy assembly threshold algorithm in optical burst switching networks

    Institute of Scientific and Technical Information of China (English)

    YANG Jiu-ru; WANG Gang; JIA Shi-lou

    2009-01-01

    To avoid burst contention efficiently, on the basis of feedback-based source flow-rate control (SFC) strategy, a novel fuzzy-control-based assembly algorithm, called dual-fuzzy assembly threshold (DFAT), is proposed in an optical burst switching network.In our algorithm, according to the variations of burst assembly period and the interarrival of burst control packet, the traffic states of edge-switching nodes and core-switching nodes are first obtained.Then, the assembly threshold of bursts is set dynamically in order to operate the source traffic management from the information of traffic states.The performance of DFAT algorithm on burst loss prob-ability is evaluated, and simulation results show that, compared with conventional assembly algorithms, the pro-posed scheme can constrain the birth of burst contention efficiently, when being a heavy load state of network.

  18. All-optical switches, unidirectional flow, and logic gates with discrete solitons in waveguide arrays.

    Science.gov (United States)

    Al Khawaja, U; Al-Marzoug, S M; Bahlouli, H

    2016-05-16

    We propose a mechanism by which a number of useful all-optical operations, such as switches, diodes, and logic gates, can be performed with a single device. An effective potential well is obtained by modulating the coupling between the waveguides through their separations. Depending on the power of a control soliton injected through the potential well, an incoming soliton will either completely transmit or reflect forming a controllable switch. We show that two such switches can work as AND, OR, NAND, and NOR logic gates. Furthermore, the same device may also function as a perfect soliton diode with adjustable polarity. We discuss the feasibility of realising such devices with current experimental setups. PMID:27409929

  19. A novel data channel fault detection mechanism in optical burst switching networks

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Fault detection in optical burst switching (OBS) networks will be a challenging task in the future. A novel mechanism based on probe burst (PB) and a new key concept is proposed to detect faults of OBS networks by sampling the health of data channels, which solve the difficulty of optical monitoring schemes while keeps the transparency of data network to Internet protocol (IP) packets. It takes full advantage of the characteristics of OBS, including architecture and signalling scheme, and introduces the excellent performances of single-hop-test used in electrical communication networks into OBS environment while avoids the shortcoming that any optical burst must undergo an optical-electric-optical (OEO) conversion.Well designed PB can provide exact criterion for judging whether protection/restoration should be excuted according to hard or soft fault identification.

  20. Investigation of code reconfigurable fibre Bragg gratings for Optical Code Division Multiple Access (OCDMA) and Optical Packet Switching (OPS) Networks

    OpenAIRE

    Tian, Chun

    2009-01-01

    This thesis documents my work in the telecommunication system laboratory at the Optoelectronics Research Centre, towards the implementation of code reconfigurable OCDMA and all-optical packet switching nodes based on fibre Bragg grating (FBG) technology. My research work involves characterizing the performance of various gratings, specifically high reflectivity, short chip duration, long code sequences, multiple phase level and tunable superstructured fiber Bragg gratings (SSFBGs), by using t...

  1. Performance evaluation of a burst-mode EDFA in an optical packet and circuit integrated network.

    Science.gov (United States)

    Shiraiwa, Masaki; Awaji, Yoshinari; Furukawa, Hideaki; Shinada, Satoshi; Puttnam, Benjamin J; Wada, Naoya

    2013-12-30

    We experimentally investigate the performance of burst-mode EDFA in an optical packet and circuit integrated system. In such networks, packets and light paths can be dynamically assigned to the same fibers, resulting in gain transients in EDFAs throughout the network that can limit network performance. Here, we compare the performance of a 'burst-mode' EDFA (BM-EDFA), employing transient suppression techniques and optical feedback, with conventional EDFAs, and those using automatic gain control and previous BM-EDFA implementations. We first measure gain transients and other impairments in a simplified set-up before making frame error-rate measurements in a network demonstration.

  2. Approximations of chaotic attractors and its circuit design based on the parameter switching algorithm%基于参数切换算法的混沌系统吸引子近似及其电路设计∗

    Institute of Scientific and Technical Information of China (English)

    罗少轩; 何博侠; 乔爱民; 王艳春

    2015-01-01

    the chaotic map. Finally, the parameter switching circuit of Rössler system is designed by introducing a square wave generator. Compared with the traditional switching chaotic circuit (switching between different systems), the design of parameter switch circuit is simpler as it does not need to change the original structure of the system. The output is affected by the frequency of the square wave. By adding an appropriate frequency square wave generator, the circuit simulation agrees with the numerical simulation. It presents a theoretical and experimental base for the practical application of the parameter switching chaotic systems.

  3. 光梯度力驱动的纳米硅基光开关∗%A nano-silicon-photonic switch driven by an optical gradient force

    Institute of Scientific and Technical Information of China (English)

    林建潇; 吴九汇; 刘爱群; 陈喆; 雷浩

    2015-01-01

    通过一道光改变另一道光的传输路线是光子集成网络中重要而长远的目标,然而,由于硅材料的光学非线性较弱,在硅材料上实现开关的全光控制难以实现.因此本文提出了一种由光梯度力驱动的纳米硅基光开关,实现了硅基光开关的全光控制.该光开关由一个部分悬空的微环谐振器和一个交叉波导结构构成,当通入一道控制光时,悬空的微环谐振器在光梯度力的作用下发生弯曲,微环谐振器的谐振波长随之发生变化,从而实现光信号的传输路线发生改变.该光开关利用纳米光子制造技术在标准绝缘体上硅晶圆上制造,实验数据得出其最小消光比为10.67 dB,最大串扰为−11.01 dB,开关时间分别为180 ns和170 ns.该光开关具有尺寸小,响应速度快,低损耗和可拓展等优点,在片上集成光路、高速信号处理以及下一代光纤通信网络中具有潜在应用.%Using light to dynamically and stably redirect the flow of another beam of light is a long-term goal for photonic-integrated circuits. However, it is challenging to realize a practically all-optical switching device in silicon owing to its weak optical nonlinearity. Major published work on all-optical switches were using single-photon absorption and two-photon absorption, which requires ultrahigh switching energy. This paper presents a nano-silicon-photonic all-optical switch driven by an optical gradient force, in which a fast switching speed with low power consumption is obtained. Each switching element is composed of a waveguide crossing connection and a micro-ring resonator. The ring resonator is side-coupled to a double-etched waveguide crossing, while the micro-ring resonator is partially released from the substrate and becomes free-standing. When the“drop”port is in“OFF”state, the wavelength of the signal light from the“input”port does not satisfy the resonant condition in the micro-ring. Therefore, light is

  4. Transient microwave bandwidth measurements of illuminated silicon switches for optical pulse-shape control of laser-fusion drivers

    International Nuclear Information System (INIS)

    The microwave transmission properties of a high-purity (≥40 kΩ·cm) single-crystal-silicon, photoconductive (PC) switch were measured while the switch was optically activated. The switch was 2.3 mm wide (the width of the microstrip electrode), 2 mm long, and 0.5 mm thick with a 0.5-mm photoconductive gap and was mounted in a 50-Ω microstrip transmission line. The switch was irradiated uniformly with a 150-ns FWHM pulse from a ND:YAG laser (wavelength = 1.064 microm). The insertion loss of the optically activated PC switch was a nearly constant -0.7 dB across the measurement system bandwidth (9 GHz). Under these illumination conditions, the switch exhibited negligible bandwidth limitations. The microstrip structure by itself had an insertion loss that increased from -0.4 dB at 1 GHz to -1.4 dB at 9 GHz

  5. Total internal reflection optical switch using the reverse breakdown of a pn junction in silicon.

    Science.gov (United States)

    Kim, Jong-Hun; Park, Hyo-Hoon

    2015-11-01

    We demonstrate a new type of silicon total-internal-reflection optical switch with a simple pn junction functioning both as a reflector and a heater. The reflector is placed between asymmetrically y-branched multimode waveguides with an inclination angle corresponding to half of the branch angle. When the reflector is at rest, incident light is reflected in accordance to the refractive index difference due to the plasma dispersion effect of the pre-doped carriers. Switching to the transmission state is attained under a reverse breakdown of the pn junction by the thermo-optic effect which smears the refractive index difference. From this switching scheme, we confirmed the switching operation with a shallow total-internal-reflection region of 1 μm width. At a 6° branch angle, an extinction ratio of 12 dB and an insertion loss of -4.2  dB are achieved along with a thermal heating power of 151.5 mW.

  6. Nanoscale on-chip all-optical logic parity checker in integrated plasmonic circuits in optical communication range

    Science.gov (United States)

    Wang, Feifan; Gong, Zibo; Hu, Xiaoyong; Yang, Xiaoyu; Yang, Hong; Gong, Qihuang

    2016-04-01

    The nanoscale chip-integrated all-optical logic parity checker is an essential core component for optical computing systems and ultrahigh-speed ultrawide-band information processing chips. Unfortunately, little experimental progress has been made in development of these devices to date because of material bottleneck limitations and a lack of effective realization mechanisms. Here, we report a simple and efficient strategy for direct realization of nanoscale chip-integrated all-optical logic parity checkers in integrated plasmonic circuits in the optical communication range. The proposed parity checker consists of two-level cascaded exclusive-OR (XOR) logic gates that are realized based on the linear interference of surface plasmon polaritons propagating in the plasmonic waveguides. The parity of the number of logic 1s in the incident four-bit logic signals is determined, and the output signal is given the logic state 0 for even parity (and 1 for odd parity). Compared with previous reports, the overall device feature size is reduced by more than two orders of magnitude, while ultralow energy consumption is maintained. This work raises the possibility of realization of large-scale integrated information processing chips based on integrated plasmonic circuits, and also provides a way to overcome the intrinsic limitations of serious surface plasmon polariton losses for on-chip integration applications.

  7. Nanoscale on-chip all-optical logic parity checker in integrated plasmonic circuits in optical communication range

    Science.gov (United States)

    Wang, Feifan; Gong, Zibo; Hu, Xiaoyong; Yang, Xiaoyu; Yang, Hong; Gong, Qihuang

    2016-01-01

    The nanoscale chip-integrated all-optical logic parity checker is an essential core component for optical computing systems and ultrahigh-speed ultrawide-band information processing chips. Unfortunately, little experimental progress has been made in development of these devices to date because of material bottleneck limitations and a lack of effective realization mechanisms. Here, we report a simple and efficient strategy for direct realization of nanoscale chip-integrated all-optical logic parity checkers in integrated plasmonic circuits in the optical communication range. The proposed parity checker consists of two-level cascaded exclusive-OR (XOR) logic gates that are realized based on the linear interference of surface plasmon polaritons propagating in the plasmonic waveguides. The parity of the number of logic 1s in the incident four-bit logic signals is determined, and the output signal is given the logic state 0 for even parity (and 1 for odd parity). Compared with previous reports, the overall device feature size is reduced by more than two orders of magnitude, while ultralow energy consumption is maintained. This work raises the possibility of realization of large-scale integrated information processing chips based on integrated plasmonic circuits, and also provides a way to overcome the intrinsic limitations of serious surface plasmon polariton losses for on-chip integration applications. PMID:27073154

  8. Investigation on TCP/IP Congestion Control in Optical Burst Switched (OBS Network

    Directory of Open Access Journals (Sweden)

    Ms. Payal Daryani

    2012-03-01

    Full Text Available Transport Control Protocol (TCP is the dominant protocol in modern communication networks, in which the issues of reliability, flow, and congestion control must be handled efficiently. In this review paper an analytical switching is used to exploit the huge bandwidth of optical fibers for future high speed internet backbone. It carries multiple packets, in their turn. Different aggregation schemes have been considered and evaluated.TCP performance greatly depends on the TCP congestion window behavior that is related to loss events occurring in the optical burst switched network, there is a special term called traffic shaping by which we control over the network according to the network load .that means we increase or decrease the send rate according to the network demand.

  9. Investigation on TCP/IP Congestion Control in Optical Burst Switched (OBS Network

    Directory of Open Access Journals (Sweden)

    Payal Daryani

    2012-03-01

    Full Text Available Transport Control Protocol (TCP is the dominant protocol in modern communication networks, in which the issues of reliability, flow, and congestion control must be handled efficiently. In this review paper an analytical switching is used to exploit the huge bandwidth of optical fibers for future high speed internet backbone. It carries multiple packets, in their turn. Different aggregation schemes have been considered and evaluated. TCP performance greatly depends on the TCP congestion window behavior that is related to loss events occurring in the optical burst switched network, there is a special term called traffic shaping by which we control over the network according to the network load .that means we increase or decrease the send rate according to the network demand.

  10. Passive all-optical polarization switch, binary logic gates, and digital processor.

    Science.gov (United States)

    Zaghloul, Y A; Zaghloul, A R M; Adibi, A

    2011-10-10

    We introduce the passive all-optical polarization switch, which modulates light with light. That switch is used to construct all the binary logic gates of two or more inputs. We discuss the design concepts and the operation of the AND, OR, NAND, and NOR gates as examples. The rest of the 16 logic gates are similarly designed. Cascading of such gates is straightforward as we show and discuss. Cascading in itself does not require a power source, but feedback at this stage of development does. The design and operation of an SR Latch is presented as one of the popular basic sequential devices used for memory cells. That completes the essential components of an all-optical polarization digital processor. The speed of such devices is well above 10 GHz for bulk implementations and is much higher for chip-size implementations. In addition, the presented devices do have the four essential characteristics previously thought unique to the microelectronic ones.

  11. Symmetric two dimensional photonic crystal coupled waveguide with point defect for optical switch application

    CERN Document Server

    Hardhienata, Hendradi

    2012-01-01

    Two dimensional (2D) photonic crystals are well known for its ability to manipulate the propagation of electromagnetic wave inside the crystal. 1D and 2D photonic crystals are relatively easier to fabricate than 3D because the former work in the microwave and far infrared regions whereas the later work in the visible region and requires smaller lattice constants. In this paper, simulation for a modified 2D PC with two symmetric waveguide channels where a defect is located inside one of the channel is performed. The simulation results show that optical switching is possible by modifying the refractive index of the defect. If more than one structure is applied this feature can potentially be applied to produce a cascade optical switch.

  12. Silicon oxide deposition for enhanced optical switching in polydimethylsiloxane-liquid crystal hybrids.

    Science.gov (United States)

    De Sio, Luciano; Vasdekis, Andreas E; Cuennet, Julien G; De Luca, Antonio; Pane, Alfredo; Psaltis, Demetri

    2011-11-01

    We report an optical switch based on a diffraction grating by combining PDMS microstructures with a photo-responsive Nematic Liquid Crystal (NLC). The grating was realized via replica molding and was subsequently coated with a thin SiO layer. SiO induced a full planar alignment of the liquid crystal. The induced parallel alignment of the LC reduces the response time of the structure by approximately an order of magnitude compared to the same structures without SiO. We explored the effect of the pump intensity on the transmission properties and time response of the switch and identified a strong dependence on the probe polarization, due to the full planar alignment in this structure. The aforementioned inclusion of the SiO layer enables enhanced performance of optical devices based on the fusion of nematogens with soft and flexible substrates. PMID:22109231

  13. High-Q silica zipper cavity for optical radiation pressure driven MOMS switch

    CERN Document Server

    Tetsumoto, Tomohiro

    2014-01-01

    We design a silica zipper cavity that has high optical and mechanical Q (quality factor) values and demonstrate numerically the feasibility of a radiation pressure driven micro opto-mechanical system (MOMS) directional switch. The silica zipper cavity has an optical Q of 6.0x10^4 and an effective mode volume Vmode of 0.66{\\lambda}^3 when the gap between two cavities is 34 nm. We found that this Q/V_mode value is five times higher than can be obtained with a single nanocavity design. The mechanical Q (Q_m) is determined by thermo-elastic damping and is 2.0x10^6 in a vacuum at room temperature. The opto-mechanical coupling rate g_OM is as high as 100 GHz/nm, which allows us to move the directional cavity-waveguide system and switch 1550-nm light with 770-nm light by controlling the radiation pressure.

  14. Optical switch based on the electrically controlled liquid crystal interface.

    Science.gov (United States)

    Komar, Andrei A; Tolstik, Alexei L; Melnikova, Elena A; Muravsky, Alexander A

    2015-06-01

    The peculiarities of the linearly polarized light beam reflection at the interface within the bulk of a nematic liquid crystal (NLC) cell with different orientations of the director are analyzed. Two methods to create the interface are considered. Combination of the planar and homeotropic orientations of the NLC director is realized by means of a spatially structured electrode under the applied voltage. In-plane patterned azimuthal alignment of the NLC director is created by the patterned rubbing alignment technique. All possible orthogonal orientations of the LC director are considered; the configurations for realization of total internal reflection are determined. The revealed relationship between the propagation of optical beams in a liquid crystal material and polarization of laser radiation has enabled realization of the spatial separation for the orthogonally polarized light beams at the interface between two regions of NLC with different director orientations (domains). Owing to variations in the applied voltage and, hence, in the refractive index gradient, the light beam propagation directions may be controlled electrically. PMID:26192675

  15. All-optical switching of diffraction gratings infiltrated with dye-doped liquid crystals

    Science.gov (United States)

    Lucchetta, D. E.; Vita, F.; Simoni, F.

    2010-12-01

    We report the realization and the characterization of an all-optical switching device based on a transmission grating recorded in a polymeric substrate infiltrated with a methyl red-doped liquid crystal. The properties of this highly nonlinear mixture are exploited to modulate the diffraction of the grating by a pump beam when a static electric field is applied. The behavior of the device is in agreement with the existing model for methyl red-doped liquid crystals.

  16. A new prediction method at the edge of optical burst switching network

    Institute of Scientific and Technical Information of China (English)

    Zhicheng Sui; Qingji Zeng; Shilin Xiao

    2005-01-01

    To achieve lower assembly delay at optical burst switching edge node, this paper proposes an approach called current weight length prediction (CWLP) to improve existing estimate mechanism in burst assembly.is introduced to make a dynamic tradeoff between the current and past traffic under different offset time.Simulation results show that CWLP can achieve a significant improvement in terms of traffic estimation in various offset time and offered load.

  17. Burst Assembly Schemes and Performance Evaluation in Optical Burst Switching Networks

    Institute of Scientific and Technical Information of China (English)

    TANG Jian-jun; JI Yue-feng

    2004-01-01

    Several proposed assemble algorithms for Optical Burst Switching (OBS) network is described, and the feature relative merits is discussed and analyzed in this paper. The authors propose an assembly mechanism FAT where time threshold is fluctuating randomly to reduce continuous blocking rate. With network simulation, the basic performance of these assembly schemes is compared and analyzed. The results show that burst loss ratio and assembly delay of the proposed FAT mechanism is better than that of exist assemble mechanism.

  18. Design of a Sample and Hold Circuit using Rail to Rail Low Voltage Compact Operational Amplifier and bootstrap Switching

    OpenAIRE

    Annu Saini; Prity Yadav

    2014-01-01

    This paper presents a low power high performance and higher sampling speed sample and hold circuit. The proposed circuit is designed at 180 nm technology and has high linearity. The circuit can be used for the ADC frontend applications and supports double sampling architecture. The proposed sample and hold circuit has common mode range beyond rail to rail and uses two differential pairs transistor stages connected in parallel as its input stage.

  19. Design of a Sample and Hold Circuit using Rail to Rail Low Voltage Compact Operational Amplifier and bootstrap Switching

    Directory of Open Access Journals (Sweden)

    Annu Saini

    2014-09-01

    Full Text Available This paper presents a low power high performance and higher sampling speed sample and hold circuit. The proposed circuit is designed at 180 nm technology and has high linearity. The circuit can be used for the ADC frontend applications and supports double sampling architecture. The proposed sample and hold circuit has common mode range beyond rail to rail and uses two differential pairs transistor stages connected in parallel as its input stage.

  20. A sub-femtojoule electrical spin-switch based on optically trapped polariton condensates

    Science.gov (United States)

    Dreismann, Alexander; Ohadi, Hamid; Del Valle-Inclan Redondo, Yago; Balili, Ryan; Rubo, Yuri G.; Tsintzos, Simeon I.; Deligeorgis, George; Hatzopoulos, Zacharias; Savvidis, Pavlos G.; Baumberg, Jeremy J.

    2016-10-01

    Practical challenges to extrapolating Moore’s law favour alternatives to electrons as information carriers. Two promising candidates are spin-based and all-optical architectures, the former offering lower energy consumption, the latter superior signal transfer down to the level of chip-interconnects. Polaritons--spinor quasi-particles composed of semiconductor excitons and microcavity photons--directly couple exciton spins and photon polarizations, combining the advantages of both approaches. However, their implementation for spintronics has been hindered because polariton spins can be manipulated only optically or by strong magnetic fields. Here we use an external electric field to directly control the spin of a polariton condensate, bias-tuning the emission polarization. The nonlinear spin dynamics offers an alternative route to switching, allowing us to realize an electrical spin-switch exhibiting ultralow switching energies below 0.5 fJ. Our results lay the foundation for development of devices based on the electro-optical control of coherent spin ensembles on a chip.