WorldWideScience

Sample records for all-optical conditional logic

  1. Photonic encryption using all optical logic.

    Energy Technology Data Exchange (ETDEWEB)

    Blansett, Ethan L.; Schroeppel, Richard Crabtree; Tang, Jason D.; Robertson, Perry J.; Vawter, Gregory Allen; Tarman, Thomas David; Pierson, Lyndon George

    2003-12-01

    With the build-out of large transport networks utilizing optical technologies, more and more capacity is being made available. Innovations in Dense Wave Division Multiplexing (DWDM) and the elimination of optical-electrical-optical conversions have brought on advances in communication speeds as we move into 10 Gigabit Ethernet and above. Of course, there is a need to encrypt data on these optical links as the data traverses public and private network backbones. Unfortunately, as the communications infrastructure becomes increasingly optical, advances in encryption (done electronically) have failed to keep up. This project examines the use of optical logic for implementing encryption in the photonic domain to achieve the requisite encryption rates. In order to realize photonic encryption designs, technology developed for electrical logic circuits must be translated to the photonic regime. This paper examines two classes of all optical logic (SEED, gain competition) and how each discrete logic element can be interconnected and cascaded to form an optical circuit. Because there is no known software that can model these devices at a circuit level, the functionality of the SEED and gain competition devices in an optical circuit were modeled in PSpice. PSpice allows modeling of the macro characteristics of the devices in context of a logic element as opposed to device level computational modeling. By representing light intensity as voltage, 'black box' models are generated that accurately represent the intensity response and logic levels in both technologies. By modeling the behavior at the systems level, one can incorporate systems design tools and a simulation environment to aid in the overall functional design. Each black box model of the SEED or gain competition device takes certain parameters (reflectance, intensity, input response), and models the optical ripple and time delay characteristics. These 'black box' models are interconnected and

  2. Rapidly Reconfigurable All-Optical Universal Logic Gates

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, L L; Kallman, J S; Bond, T C

    2006-06-21

    We present designs and simulations for a highly cascadable, rapidly reconfigurable, all-optical, universal logic gate. We will discuss the gate's expected performance, e.g. speed, fanout, and contrast ratio, as a function of the device layout and biasing conditions. The gate is a three terminal on-chip device that consists of: (1) the input optical port, (2) the gate selection port, and (3) the output optical port. The device can be built monolithically using a standard multiple quantum well graded index separate confinement heterostructure laser configuration. The gate can be rapidly and repeatedly reprogrammed to perform any of the basic digital logic operations by using an appropriate analog electrical or optical signal at the gate selection port. Specifically, the same gate can be selected to execute one of the 2 basic unary operations (NOT or COPY), or one of the 6 binary operations (OR, XOR, AND, NOR, XNOR, or NAND), or one of the many logic operations involving more than two inputs. The speed of the gate for logic operations as well as for reprogramming the function of the gate is primarily limited to the small signal modulation speed of a laser, which can be on the order of tens of GHz. The reprogrammable nature of the universal gate offers maximum flexibility and interchangeability for the end user since the entire application of a photonic integrated circuit built from cascaded universal logic gates can be changed simply by adjusting the gate selection port signals.

  3. All-optical logic-gates based on bacteriorhodopsin film

    Institute of Scientific and Technical Information of China (English)

    Chen Gui-Ying; Zhang Chun-Ping; Guo Zong-Xia; Tian Jian-Guo; Zhang Guang-Yin; Song Qi-Wang

    2005-01-01

    Based on self-diffraction in bacteriorhodopsin (bR) film, we propose all-optical NOT, XOR, half adder and XNOR logic operations. Using the relation between diffraction light and the polarization states of recording beams, we demonstrate NOT and XNOR logic operations. Studying the relation of polarization states among the diffracting, recording and reading beams, we implement XOR logic and half adder operations with three inputs. The methods are simple and practicable.

  4. Photonic encryption : modeling and functional analysis of all optical logic.

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Jason D.; Schroeppel, Richard Crabtree; Robertson, Perry J.

    2004-10-01

    With the build-out of large transport networks utilizing optical technologies, more and more capacity is being made available. Innovations in Dense Wave Division Multiplexing (DWDM) and the elimination of optical-electrical-optical conversions have brought on advances in communication speeds as we move into 10 Gigabit Ethernet and above. Of course, there is a need to encrypt data on these optical links as the data traverses public and private network backbones. Unfortunately, as the communications infrastructure becomes increasingly optical, advances in encryption (done electronically) have failed to keep up. This project examines the use of optical logic for implementing encryption in the photonic domain to achieve the requisite encryption rates. This paper documents the innovations and advances of work first detailed in 'Photonic Encryption using All Optical Logic,' [1]. A discussion of underlying concepts can be found in SAND2003-4474. In order to realize photonic encryption designs, technology developed for electrical logic circuits must be translated to the photonic regime. This paper examines S-SEED devices and how discrete logic elements can be interconnected and cascaded to form an optical circuit. Because there is no known software that can model these devices at a circuit level, the functionality of S-SEED devices in an optical circuit was modeled in PSpice. PSpice allows modeling of the macro characteristics of the devices in context of a logic element as opposed to device level computational modeling. By representing light intensity as voltage, 'black box' models are generated that accurately represent the intensity response and logic levels in both technologies. By modeling the behavior at the systems level, one can incorporate systems design tools and a simulation environment to aid in the overall functional design. Each black box model takes certain parameters (reflectance, intensity, input response), and models the optical ripple

  5. Expanded all-optical programmable logic array based on multi-input/output canonical logic units.

    Science.gov (United States)

    Lei, Lei; Dong, Jianji; Zou, Bingrong; Wu, Zhao; Dong, Wenchan; Zhang, Xinliang

    2014-04-21

    We present an expanded all-optical programmable logic array (O-PLA) using multi-input and multi-output canonical logic units (CLUs) generation. Based on four-wave mixing (FWM) in highly nonlinear fiber (HNLF), two-input and three-input CLUs are simultaneously achieved in five different channels with an operation speed of 40 Gb/s. Clear temporal waveforms and wide open eye diagrams are successfully observed. The effectiveness of the scheme is validated by extinction ratio and optical signal-to-noise ratio measurements. The computing capacity, defined as the total amount of logic functions achieved by the O-PLA, is discussed in detail. For a three-input O-PLA, the computing capacity of the expanded CLUs-PLA is more than two times as large as that of the standard CLUs-PLA, and this multiple will increase to more than three and a half as the idlers are individually independent.

  6. Chip-integrated ultrawide-band all-optical logic comparator in plasmonic circuits

    OpenAIRE

    Lu, Cuicui; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2014-01-01

    Optical computing opens up the possibility for the realization of ultrahigh-speed and ultrawide-band information processing. Integrated all-optical logic comparator is one of the indispensable core components of optical computing systems. Unfortunately, up to now, no any nanoscale all-optical logic comparator suitable for on-chip integration applications has been realized experimentally. Here, we report a subtle and effective technical solution to circumvent the obstacles of inherent Ohmic lo...

  7. 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.

  8. Implementation of tristate logic based all optical flip-flop with nonlinear material

    Institute of Scientific and Technical Information of China (English)

    Partha Ghosh; Sourangshu Mukhopadhyay

    2005-01-01

    @@ The advantages of multivalued logic in optical parallel computation need no introduction. There are lots of proposals, already reported, where tristate, quarternary state logic operations can be performed with optics. Here we report a new approach to implement tristate logic based all optical flip-flop using optical nonlinear material. The concept and the principle of operation of this type of flip-flop are different from that of the conventional binary one.

  9. Chip-integrated ultrawide-band all-optical logic comparator in plasmonic circuits

    Science.gov (United States)

    Lu, Cuicui; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2014-01-01

    Optical computing opens up the possibility for the realization of ultrahigh-speed and ultrawide-band information processing. Integrated all-optical logic comparator is one of the indispensable core components of optical computing systems. Unfortunately, up to now, no any nanoscale all-optical logic comparator suitable for on-chip integration applications has been realized experimentally. Here, we report a subtle and effective technical solution to circumvent the obstacles of inherent Ohmic losses of metal and limited propagation length of SPPs. A nanoscale all-optical logic comparator suitable for on-chip integration applications is realized in plasmonic circuits directly. The incident single-bit (or dual-bit) logic signals can be compared and the comparison results are endowed with different logic encodings. An ultrabroad operating wavelength range from 700 to 1000 nm, and an ultrahigh output logic-state contrast-ratio of more than 25 dB are realized experimentally. No high power requirement is needed. Though nanoscale SPP light source and the logic comparator device are integrated into the same plasmonic chip, an ultrasmall feature size is maintained. This work not only paves a way for the realization of complex logic device such as adders and multiplier, but also opens up the possibility for realizing quantum solid chips based on plasmonic circuits.

  10. Chip-integrated ultrawide-band all-optical logic comparator in plasmonic circuits.

    Science.gov (United States)

    Lu, Cuicui; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2014-01-27

    Optical computing opens up the possibility for the realization of ultrahigh-speed and ultrawide-band information processing. Integrated all-optical logic comparator is one of the indispensable core components of optical computing systems. Unfortunately, up to now, no any nanoscale all-optical logic comparator suitable for on-chip integration applications has been realized experimentally. Here, we report a subtle and effective technical solution to circumvent the obstacles of inherent Ohmic losses of metal and limited propagation length of SPPs. A nanoscale all-optical logic comparator suitable for on-chip integration applications is realized in plasmonic circuits directly. The incident single-bit (or dual-bit) logic signals can be compared and the comparison results are endowed with different logic encodings. An ultrabroad operating wavelength range from 700 to 1000 nm, and an ultrahigh output logic-state contrast-ratio of more than 25 dB are realized experimentally. No high power requirement is needed. Though nanoscale SPP light source and the logic comparator device are integrated into the same plasmonic chip, an ultrasmall feature size is maintained. This work not only paves a way for the realization of complex logic device such as adders and multiplier, but also opens up the possibility for realizing quantum solid chips based on plasmonic circuits.

  11. Two all-optical logic gates in a single photonic interferometer

    Science.gov (United States)

    Araújo, Antônio; Oliveira, Antônio; Martins, Francisco; Coelho, Amarílio; Fraga, Wilton; Nascimento, José

    2015-11-01

    In this paper is presented the all-optical AND and OR gates with high contrast ratio in a single interferometric configuration, i.e., when two logic signals are modulated in the input of the interferometer, so we have the OR gate in the first output and the AND gate in the second output. These logic gates were obtained by numerical investigation of the Mach-Zehnder interferometer constituted of dual-core nonlinear photonic crystal fiber operating with ultrashort fundamental solitons of 100 fs. To represent the logic information, pulse amplitude modulation by amplitude shift-keying was used.

  12. 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.

  13. Terahertz all-optical NOR and AND logic gates based on 2D photonic crystals

    Science.gov (United States)

    Parandin, Fariborz; Karkhanehchi, Mohammad Mehdi

    2017-01-01

    Usually, photonic crystals are used in designing optical logic gates. This study focuses on the design and simulation of an all optical NOR and AND logic gates based on two dimensional photonic crystals. The simplicity of the proposed structure is a characteristic feature of this designation. Finite Difference Time Domain (FDTD) as well as Plane Wave Expansion (PWE) methods have been used for this structural analysis. The simulation results revealed an increase in the interval between "zero" and "one" logic levels. Also, the simple structure and its small size demonstrate the usefulness of this structure in optical integrated circuits. The proposed optical gates can operate with a bit rate of about 1.54 Tbit/s.

  14. Alternative approach of conducting phase-modulated all-optical logic gates

    Science.gov (United States)

    Chakraborty, Bikash; Mukhopadhyay, Sourangshu

    2009-03-01

    It is well established that optical devices and components are more advantageous than their electronic counterparts because of inherent parallelism in optics. Basically electronics are found to be very unsuitable in high speed (above gigahertz) data processing systems whereas tremendous operational speed (in the range of terahertz) can be achieved with the help of optics. The parallelism of optics and the properties of low loss transmission make optics a powerful technology for digital computing and processing and in long-range communications. Again it is well established that logic gates are the basic building blocks of any computing or data processing system. Therefore, any optical data processor needs suitable optically run logic gates. A method of conducting phase-modulated all-optical logic gates is proposed. Here we will exploit the advantages of phase modulation not only in processing but also in encoding as well decoding also.

  15. Ultracompact all-optical logic gates based on nonlinear plasmonic nanocavities

    Science.gov (United States)

    Yang, Xiaoyu; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2017-01-01

    In this study, nanoscale integrated all-optical XNOR, XOR, and NAND logic gates were realized based on all-optical tunable on-chip plasmon-induced transparency in plasmonic circuits. A large nonlinear enhancement was achieved with an organic composite cover layer based on the resonant excitation-enhancing nonlinearity effect, slow light effect, and field confinement effect provided by the plasmonic nanocavity mode, which ensured a low excitation power of 200 μW that is three orders of magnitude lower than the values in previous reports. A feature size below 600 nm was achieved, which is a one order of magnitude lower compared to previous reports. The contrast ratio between the output logic states "1" and "0" reached 29 dB, which is among the highest values reported to date. Our results not only provide an on-chip platform for the study of nonlinear and quantum optics but also open up the possibility for the realization of nanophotonic processing chips based on nonlinear plasmonics.

  16. IST-LASAGNE: Towards all-optical label swapping employing optical logic gates and optical flip-flops

    DEFF Research Database (Denmark)

    Ramos, F.; Kehayas, E.; Martinez, J.M.

    2005-01-01

    The Information Society Technologies - all-optical LAbel SwApping employing optical logic Gates in NEtwork nodes (IST-LASAGNE) project aims at designing and implementing the first, modular, scalable, and truly all-optical photonic router capable of operating at 40 Gb/s. The results of the first...

  17. All-Optical Arithmetic and Combinatorial Logic Circuits with High-Q Bacteriorhodopsin Coated Microcavities

    CERN Document Server

    Roy, Sukhdev; Topolancik, Juraj; Vollmer, Frank

    2010-01-01

    We present designs of all-optical computing circuits, namely, half-full adder/subtractor, de-multiplexer, multiplexer, and an arithmetic unit, based on bacteriorhodopsin (BR) protein coated microcavity switch in a tree architecture. The basic all-optical switch consists of an input infrared (IR) laser beam at 1310 nm in a single mode fiber (SMF-28) switched by a control pulsed laser beam at 532 nm, which triggers the change in the resonance condition on a silica bead coated with BR between two tapered fibers. We show that fast switching of 50 us can be achieved by injecting a blue laser beam at 410 nm that helps in truncating the BR photocycle at the M intermediate state. Realization of all-optical switch with BR coated microcavity switch has been done experimentally. Based on this basic switch configuration, designs of all-optical higher computing circuits have been presented. The design requires 2n-1 switches to realize n bit computation. The proposed designs require less number of switches than terahertz o...

  18. Ultrafast all-optical arithmetic logic based on hydrogenated amorphous silicon microring resonators

    Science.gov (United States)

    Gostimirovic, Dusan; Ye, Winnie N.

    2016-03-01

    For decades, the semiconductor industry has been steadily shrinking transistor sizes to fit more performance into a single silicon-based integrated chip. This technology has become the driving force for advances in education, transportation, and health, among others. However, transistor sizes are quickly approaching their physical limits (channel lengths are now only a few silicon atoms in length), and Moore's law will likely soon be brought to a stand-still despite many unique attempts to keep it going (FinFETs, high-k dielectrics, etc.). This technology must then be pushed further by exploring (almost) entirely new methodologies. Given the explosive growth of optical-based long-haul telecommunications, we look to apply the use of high-speed optics as a substitute to the digital model; where slow, lossy, and noisy metal interconnections act as a major bottleneck to performance. We combine the (nonlinear) optical Kerr effect with a single add-drop microring resonator to perform the fundamental AND-XOR logical operations of a half adder, by all-optical means. This process is also applied to subtraction, higher-order addition, and the realization of an all-optical arithmetic logic unit (ALU). The rings use hydrogenated amorphous silicon as a material with superior nonlinear properties to crystalline silicon, while still maintaining CMOS-compatibility and the many benefits that come with it (low cost, ease of fabrication, etc.). Our method allows for multi-gigabit-per-second data rates while maintaining simplicity and spatial minimalism in design for high-capacity manufacturing potential.

  19. Ultracompact all-optical XOR logic gate in a slow-light silicon photonic crystal waveguide.

    Science.gov (United States)

    Husko, C; Vo, T D; Corcoran, B; Li, J; Krauss, T F; Eggleton, B J

    2011-10-10

    We demonstrate an ultracompact, chip-based, all-optical exclusive-OR (XOR) logic gate via slow-light enhanced four-wave mixing (FWM) in a silicon photonic crystal waveguide (PhCWG). We achieve error-free operation (<10⁻⁹) for 40 Gbit/s differential phase-shift keying (DPSK) signals with a 2.8 dB power penalty. Slowing the light to vg = c/32 enables a FWM conversion efficiency, η, of -30 dB for a 396 μm device. The nonlinear FWM process is enhanced by 20 dB compared to a relatively fast mode of vg = c/5. The XOR operation requires ≈ 41 mW, corresponding to a switching energy of 1 pJ/bit. We compare the slow-light PhCWG device performance with experimentally demonstrated XOR DPSK logic gates in other platforms and discuss scaling the device operation to higher bit-rates. The ultracompact structure suggests the potential for device integration.

  20. All-optical transistor- and diode-action and logic gates based on anisotropic nonlinear responsive liquid crystal.

    Science.gov (United States)

    Wang, Cheng-Yu; Chen, Chun-Wei; Jau, Hung-Chang; Li, Cheng-Chang; Cheng, Chiao-Yu; Wang, Chun-Ta; Leng, Shi-Ee; Khoo, Iam-Choon; Lin, Tsung-Hsien

    2016-08-05

    In this paper, we show that anisotropic photosensitive nematic liquid crystals (PNLC) made by incorporating anisotropic absorbing dyes are promising candidates for constructing all-optical elements by virtue of the extraordinarily large optical nonlinearity of the nematic host. In particular, we have demonstrated several room-temperature 'prototype' PNLC-based all-optical devices such as optical diode, optical transistor and all primary logic gate operations (OR, AND, NOT) based on such optical transistor. Owing to the anisotropic absorption property and the optical activity of the twist alignment nematic cell, spatially non-reciprocal transmission response can be obtained within a sizeable optical isolation region of ~210 mW. Exploiting the same mechanisms, a tri-terminal configuration as an all-optical analogue of a bipolar junction transistor is fabricated. Its ability to be switched by an optical field enables us to realize an all-optical transistor and demonstrate cascadability, signal fan-out, logic restoration, and various logical gate operations such as OR, AND and NOT. Due to the possibility of synthesizing anisotropic dyes and wide ranging choice of liquid crystals nonlinear optical mechanisms, these all-optical operations can be optimized to have much lower thresholds and faster response speeds. The demonstrated capabilities of these devices have shown great potential in all-optical control system and photonic integrated circuits.

  1. Design and analysis of polarization independent all-optical logic gates in silicon-on-insulator photonic crystal

    Science.gov (United States)

    Rani, Preeti; Kalra, Yogita; Sinha, R. K.

    2016-09-01

    In this paper, we have reported design and analysis of polarization independent all optical logic gates in silicon-on-insulator photonic crystal consisting of two dimensional honeycomb lattices with two different air holes exhibiting photonic band gap for both TE and TM mode in the optical communication window. The proposed structures perform as an AND optical logic gate and all the optical logic gates based on the phenomenon of interference. The response period and bit rate for TE and TM polarizations at a wavelength of 1.55 μm show improved results as reported earlier.

  2. All-optical reconfigurable multi-logic gates based on nonlinear polarization rotation effect in a single SOA

    Institute of Scientific and Technical Information of China (English)

    Lilin Yi; Weisheng Hu; Hao He; Yi Dong; Yaohui Jin; Weiqiang Sun

    2011-01-01

    We demonstrate an all-optical reconfigurable logic gate based on dominant nonlinear polarization rotation accompanied with cross-gain modulation effect in a singlc semiconductor optical amplifier (SOA). Five logic functions, including NOT, OR, NOR, AND, and NAND, are realized using 10-Gb/s on-off keying signals with flexible wavelength tunability. The operation principle is explained in detail. By adjusting polarization controllers, multiple logic functions corresponding to different input polarization states are separately achieved using a single SOA with high flexibility.%@@ We demonstrate an all-optical reconfigurable logic gate based on dominant nonlinear polarization rotation accompanied with cross-gain modulation effect in a single semiconductor optical amplifier (SOA).Five logic functions, including NOT, OR, NOR, AND, and NAND, are realized using 10-Gb/s on-off keying signals with flexible wavelength tunability.The operation principle is explained in detail.By adjusting polarization controllers, multiple logic functions corresponding to different input polarization states are separately achieved using a single SOA with high flexibility.

  3. Controllable all-optical stochastic logic gates and their delay storages based on the cascaded VCSELs with optical-injection

    Science.gov (United States)

    Zhong, Dongzhou; Luo, Wei; Xu, Geliang

    2016-09-01

    Using the dynamical properties of the polarization bistability that depends on the detuning of the injected light, we propose a novel approach to implement reliable all-optical stochastic logic gates in the cascaded vertical cavity surface emitting lasers (VCSELs) with optical-injection. Here, two logic inputs are encoded in the detuning of the injected light from a tunable CW laser. The logic outputs are decoded from the two orthogonal polarization lights emitted from the optically injected VCSELs. For the same logic inputs, under electro-optic modulation, we perform various digital signal processing (NOT, AND, NAND, XOR, XNOR, OR, NOR) in the all-optical domain by controlling the logic operation of the applied electric field. Also we explore their delay storages by using the mechanism of the generalized chaotic synchronization. To quantify the reliabilities of these logic gates, we further demonstrate their success probabilities. Project supported by the National Natural Science Foundation of China (Grant No. 61475120) and the Innovative Projects in Guangdong Colleges and Universities, China (Grant Nos. 2014KTSCX134 and 2015KTSCX146).

  4. 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

  5. Application of bistable optical logic gate arrays to all-optical digital parallel processing

    Science.gov (United States)

    Walker, A. C.

    1986-05-01

    Arrays of bistable optical gates can form the basis of an all-optical digital parallel processor. Two classes of signal input geometry exist - on- and off-axis - and lead to distinctly different device characteristics. The optical implementation of multisignal fan-in to an array of intrinsically bistable optical gates using the more efficient off-axis option is discussed together with the construction of programmable read/write memories from optically bistable devices. Finally the design of a demonstration all-optical parallel processor incorporating these concepts is presented.

  6. All-optical logical gates based on pump-induced resonant nonlinearity in an erbium-doped fiber coupler.

    Science.gov (United States)

    Li, Qiliang; Zhang, Zhen; Li, Dongqiang; Zhu, Mengyun; Tang, Xianghong; Li, Shuqin

    2014-12-01

    In this paper, we theoretically investigate all-optical logical gates based on the pump-induced resonant nonlinearity in an erbium-doped fiber coupler. The resonant nonlinearity yielded by the optical transitions between the (4)I(15/2) states and (4)I(13/2) states in Er(3+) induces the refractive index to change, which leads to switching between two output ports. First, we do a study on the switching performance, and calculate the extinction ratio (Xratio) of the device. Second, using the Xratio, we obtain the truth tables of the device. The results reveal that compared with other undoped nonlinear couplers, the erbium-doped fiber coupler can drop the switching threshold power. We also obtain different logic gates and logic operations in the cases of the same phase and different phase of two initial signals by changing the pump power.

  7. Fixed weight Hopfield Neural Network based on optical implementation of all-optical MZI-XNOR logic gate

    Science.gov (United States)

    Nugamesh Mutter, Kussay; Mat Jafri, Mohd Zubir; Abdul Aziz, Azlan

    2010-05-01

    Many researches are conducted to improve Hopfield Neural Network (HNN) performance especially for speed and memory capacity in different approaches. However, there is still a significant scope of developing HNN using Optical Logic Gates. We propose here a new model of HNN based on all-optical XNOR logic gates for real time color image recognition. Firstly, we improved HNN toward optimum learning and converging operations. We considered each unipolar image as a set of small blocks of 3-pixels as vectors for HNN. This enables to save large number of images in the net with best reaching into global minima, and because there are only eight fixed states of weights so that only single iteration performed to construct a vector with stable state at minimum energy. HNN is useless in dealing with data not in bipolar representation. Therefore, HNN failed to work with color images. In RGB bands each represents different values of brightness, for d-bit RGB image it is simply consists of d-layers of unipolar. Each layer is as a single unipolar image for HNN. In addition, the weight matrices with stability of unity at the diagonal perform clear converging in comparison with no self-connecting architecture. Synchronously, each matrix-matrix multiplication operation would run optically in the second part, since we propose an array of all-optical XOR gates, which uses Mach-Zehnder Interferometer (MZI) for neurons setup and a controlling system to distribute timely signals with inverting to achieve XNOR function. The primary operation and simulation of the proposal HNN is demonstrated.

  8. All-Optical Logic Gates and Wavelength Conversion Via the Injection-Locking of a Fabry-Perot Semiconductor Laser

    Science.gov (United States)

    2013-03-21

    Figure 18: An all-optical half- adder involving all-optical NAND, AND, XNOR, and XOR gates [44...XNOR gates, XOR gates, comparators, flip-flops, and half- adders can be achieved using multiple SMFP-LDs in a variety of configurations [47]. For...half- adder . Figure 18: An all-optical half- adder involving all-optical NAND, AND, XNOR, and XOR gates [47]. 55 The all-optical half- adder

  9. All-optical logic gate based on transient grating from disperse red 1 doped organic-inorganic hybrid films with an improved figure of merit

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Tianxi; Que, Wenxiu, E-mail: wxque@mail.xjtu.edu.cn; Shao, Jinyou [Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, International Center for Dielectric Research, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi' an Jiaotong University, Xi' an 710049, Shaanxi (China); Wang, Yushu [School of Materials Science and Engineering, Georgia Institute of Technology, 500 Tenth Street NW, Atlanta, Georgia 30318 (United States)

    2015-10-21

    Azobenzene dyes have large refractive index near their main resonance, but the poor figure of merit (FOM) limits their potential for all-optical applications. To improve this situation, disperse red 1 (DR1) molecules were dispersed in a sol-gel germanium/Ormosil organic-inorganic hybrid matrix. Z-scan measurement results showed a good compatibility between the dopant and the matrix, and also, an improved FOM was obtained as compared to the DR1/polymer films reported previously. To demonstrate the all-optical signal processing effect, a cw Nd:YAG laser emitting at 532 nm and a He-Ne laser emitting at 632.8 nm were used as pump and probe beams, respectively. DR1 acts as an initiator of the photo-induced transient holographic grating, which is attributed to the trans-cis-trans photoisomerization. Thus, a three inputs AND all-optical logic gate was achieved by using choppers with different frequencies. The detailed mechanism of operation is discussed. These results indicate that the DR1 doped germanium/Ormosil organic-inorganic hybrid film with an improved FOM has a great potential in all-optical devices around its main resonance.

  10. Conditionals and Modularity in General Logics

    CERN Document Server

    Gabbay, Dov M

    2011-01-01

    This text centers around three main subjects. The first is the concept of modularity and independence in classical logic and nonmonotonic and other nonclassical logic, and the consequences on syntactic and semantical interpolation and language change. In particular, we will show the connection between interpolation for nonmonotonic logic and manipulation of an abstract notion of size. Modularity is essentially the ability to put partial results achieved independently together for a global result. The second aspect of the book is the authors' uniform picture of conditionals, including many-valu

  11. All-optical analog comparator

    OpenAIRE

    Pu Li; Xiaogang Yi; Xianglian Liu; Dongliang Zhao; Yongpeng Zhao; Yuncai Wang

    2016-01-01

    An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical ‘1’ or ‘0’ by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical device...

  12. All-optical analog comparator

    Science.gov (United States)

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Zhao, Dongliang; Zhao, Yongpeng; Wang, Yuncai

    2016-08-01

    An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical ‘1’ or ‘0’ by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical devices. In this work, we propose a new concept of an all-optical analog comparator and numerically demonstrate an implementation based on a quarter-wavelength-shifted distributed feedback laser diode (QWS DFB-LD) with multiple quantum well (MQW) structures. Our results show that the all-optical comparator is very well suited for true AO-ADCs, enabling the whole digital conversion from an analog optical signal (continuous-time signal or discrete pulse signal) to a binary representation totally in the optical domain. In particular, this all-optical analog comparator possesses a low threshold power (several mW), high extinction ratio (up to 40 dB), fast operation rate (of the order of tens of Gb/s) and a step-like transfer function.

  13. All-optical bit-pattern recognition in data segments using logic AND and XOR in a single all-active MZI wavelength converter

    DEFF Research Database (Denmark)

    Nielsen, Mads Lønstrup; Fjelde, T; Buron, J D;

    2002-01-01

    A novel and cost-effective scheme far comparing a segment of an incoming data stream to an expected sequence, using a single, all- active MZI is proposed. The comparator comprises the logic AND and XOR functions, and is demonstrated at 10 Gb/s......A novel and cost-effective scheme far comparing a segment of an incoming data stream to an expected sequence, using a single, all- active MZI is proposed. The comparator comprises the logic AND and XOR functions, and is demonstrated at 10 Gb/s...

  14. All-optical repeater.

    Science.gov (United States)

    Silberberg, Y

    1986-06-01

    An all-optical device containing saturable gain, saturable loss, and unsaturable loss is shown to transform weak, distorted optical pulses into uniform standard-shape pulses. The proposed device performs thresholding, amplification, and pulse shaping as required from an optical repeater. It is shown that such a device could be realized by existing semiconductor technology.

  15. Predictive Condition Monitoring of Induction Motor Bearing Using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Prof. Rakeshkumar A. Patel

    2012-10-01

    Full Text Available Induction motor is critical component in industrial processes and is frequently integrated in commercially available equipment. Safety, reliability, efficiency and performance are the major concerns of induction motor applications. Due to high reliability requirements and cost of breakdown, condition monitoring, diagnosis and Protection increasing importance. Protection of an induction motor (IM against possible problems, such as stator faults, rotor faults and mechanical faults, occurring in the course of its operation is very important, because it is very popular in industries. Bearing fault is well known mechanical fault of IM.41�0faults related to bearing in IM. To avoid break down of IM condition monitoring of motor bearing condition is very important during the normal operation. Various classical and AI techniques like fuzzy logic, neural network, neuro-fuzzy are used for condition monitoring and diagnosis of IM. Among the above mentioned AI techniques, Fuzzy logic is the best technique for condition monitoring and diagnosis of IM bearing condition. Therefore, the present paper focuses on fuzzy logic technique. In this paper Fuzzy logic is design for the condition monitoring and diagnosis of induction motor bearing condition using motor current and speed. After applying Fuzzy logic it has been seen that continuous monitoring of the current and speed values of the motor conditioned monitoring and diagnosis of induction motor bearing condition can be done.

  16. ALL OPTICAL 3-BIT SERIAL INPUT SHIFT REGISTER DESIGN

    Directory of Open Access Journals (Sweden)

    VIKRANT K SRIVASTAVA,

    2010-08-01

    Full Text Available In this Paper, we present all-optical shift Register logic with complete Boolean functionality as a representative circuit for modeling and optimization of monolithically integrated components. Proposed optical logic unit is based on nonlinear effects in semiconductor optical amplifiers (SOA. We show a strategy of optical pulse propagation in SOA based on coupled nonlinear equations describing XGM and FWM effects. These equations are first solved togenerate the pump, probe and conjugate pulses in a SOA. The pulse behavior are analyzed and applied to realize behavior of all-optical NAND gate. Next, the logic is used to implement All-Optical Flip-Flop logic, and its function is verified with the help of truth table. Finally with the help of three Flip Flop a 3-bit shift register is proposed. The full design is simple, compact, economical, thermally stable and integration capable.

  17. All-optical reservoir computing.

    Science.gov (United States)

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  18. All-optical pressure sensor

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to an all-optical pressure sensor comprising a waveguide accommodating a distributed Bragg reflector. Pressure sensing can then be provided by utilizing effective index modulation of the waveguide and detection of a wavelength shift of light reflected from the Bragg...... reflector. Sound sensing may also be provided thereby having an all-optical microphone. One embodiment of the invention relates to an optical pressure sensor comprising at least one outer membrane and a waveguide, the waveguide comprising at least one core for confining and guiding light,at least one...... distributed Bragg reflector located in said at least one core, and at least one inner deflecting element forming at least a part of the core,wherein the pressure sensor is configured such that the geometry and/or dimension of the at least one core is changed when the at least one outer membrane is submitted...

  19. All-optical photoacoustic microscopy

    Directory of Open Access Journals (Sweden)

    Sung-Liang Chen

    2015-12-01

    Full Text Available Three-dimensional photoacoustic microscopy (PAM has gained considerable attention within the biomedical imaging community during the past decade. Detecting laser-induced photoacoustic waves by optical sensing techniques facilitates the idea of all-optical PAM (AOPAM, which is of particular interest as it provides unique advantages for achieving high spatial resolution using miniaturized embodiments of the imaging system. The review presents the technology aspects of optical-sensing techniques for ultrasound detection, such as those based on optical resonators, as well as system developments of all-optical photoacoustic systems including PAM, photoacoustic endoscopy, and multi-modality microscopy. The progress of different AOPAM systems and their representative applications are summarized.

  20. Universal quantum computation using all-optical hybrid encoding

    Institute of Scientific and Technical Information of China (English)

    郭奇; 程留永; 王洪福; 张寿

    2015-01-01

    By employing displacement operations, single-photon subtractions, and weak cross-Kerr nonlinearity, we propose an alternative way of implementing several universal quantum logical gates for all-optical hybrid qubits encoded in both single-photon polarization state and coherent state. Since these schemes can be straightforwardly implemented only using local operations without teleportation procedure, therefore, less physical resources and simpler operations are required than the existing schemes. With the help of displacement operations, a large phase shift of the coherent state can be obtained via currently available tiny cross-Kerr nonlinearity. Thus, all of these schemes are nearly deterministic and feasible under current technology conditions, which makes them suitable for large-scale quantum computing.

  1. 基于非线性材料二次谐波与混频特性非逻辑门运算的全光实现%All-Optical Implementation of Inversion Logic Operation by Second Harmonic Generation and Wave Mixing Character of Some Non-Linear Material

    Institute of Scientific and Technical Information of China (English)

    Sisir Kumar Garai; Debojyati Samanta; Sourangshu Mukhopadhyay

    2008-01-01

    Optics has already been proved as a successful candidate for conducting parallel logic, arithmetic and algebraic operations. Several all-optical data processors were proposed since last few decades. To implement these systems, different data encoding decoding techniques such as polarization encoding, tristate, quartenary state, multivalued state, symbolic substitution technique etc. have already been proposed. All these are done to use optics in a suitable platform. We propose here a new concept of encoding data by adopting frequencies variation technique for conducting a inversion operation successfully.

  2. All-optical digital processor based on harmonic generation phenomena

    Science.gov (United States)

    Shcherbakov, Alexandre S.; Rakovsky, Vsevolod Y.

    1990-07-01

    Digital optical processors are designed to combine ultra- parallel data procesing capabilities of optical aystems cnd high accur&cy of performed computations. The ultimate limit of the processing rate can be anticipated from all-optical parcllel erchitecturea based on networks o logic gates using materials exibiting strong electronic nonlinearities with response times less than 1O seconds1.

  3. The All Optical New Universal Gate Using TOAD

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Maity

    2014-06-01

    Full Text Available Since the seventies of the past century the reversible logic has originated as an unconventional form of computing. It is new relatively in the area of extensive applications in quantum computing, low power CMOS, DNA computing, digital signal processing (DSP, nanotechnology, communication, optical computing, computer graphics, bio information, etc .Here we present and configure a new TAND gate in all-optical domain and also in this paper we have explained their principle of operations and used a theoretical model to fulfil this task, finally supporting through numerical simulations. In the field of ultra-fast all-optical signal processing Terahertz Optical Asymmetric Demultiplexer (TOAD, semiconductor optical amplifier (SOA-based, has an important function. The different logical (composing of Boolean function operations can be executed by designed circuits with TAND gate in the domain of universal logic-based information processing.

  4. All-optical pseudorandom bit sequences generator based on TOADs

    Science.gov (United States)

    Sun, Zhenchao; Wang, Zhi; Wu, Chongqing; Wang, Fu; Li, Qiang

    2016-03-01

    A scheme for all-optical pseudorandom bit sequences (PRBS) generator is demonstrated with optical logic gate 'XNOR' and all-optical wavelength converter based on cascaded Tera-Hertz Optical Asymmetric Demultiplexer (TOADs). Its feasibility is verified by generation of return-to-zero on-off keying (RZ-OOK) 263-1 PRBS at the speed of 1 Gb/s with 10% duty radio. The high randomness of ultra-long cycle PRBS is validated by successfully passing the standard benchmark test.

  5. All-optical fast random number generator.

    Science.gov (United States)

    Li, Pu; Wang, Yun-Cai; Zhang, Jian-Zhong

    2010-09-13

    We propose a scheme of all-optical random number generator (RNG), which consists of an ultra-wide bandwidth (UWB) chaotic laser, an all-optical sampler and an all-optical comparator. Free from the electric-device bandwidth, it can generate 10Gbit/s random numbers in our simulation. The high-speed bit sequences can pass standard statistical tests for randomness after all-optical exclusive-or (XOR) operation.

  6. MODELLING OF AIR CONDITIONING SYSTEM BY FUZZY LOGIC APPROACH

    Directory of Open Access Journals (Sweden)

    Ahmet ÖZEK

    2004-03-01

    Full Text Available One of the main problems in control systems is the difficulty to form the mathematical model associated with the control mechanism. Even though this model can be formed, to realize the application with conventional logic may cause very complex problems. The fuzzy logic without using mathematical model of control system can create control mechanism only with the help of linguistic variables. In this article the modeling has been realized by fuzzy logic.

  7. All optical regeneration using semiconductor devices

    DEFF Research Database (Denmark)

    Mørk, Jesper; Öhman, Filip; Tromborg, Bjarne

    All-optical regeneration is a key functionality for implementing all-optical networks. We present a simple theory for the bit-error-rate in links employing all-optical regenerators, which elucidates the interplay between the noise and and nonlinearity of the regenerator. A novel device structure ...... is analyzed, emphasizing general aspects of active semiconductor waveguides....

  8. All-Optical Reversible Hybrid New Gate using TOAD

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Maity

    2014-03-01

    Full Text Available Reversible logic is emerged as a promising computing paradigm with applications in low-power CMOS, quantum computing, optical computing and nanotechnology. Optical logic gates become potential component to work at macroscopic (light pulses carry information, or quantum (single photon carries information levels with high efficiency. In this paper, we propose a novel scheme of Hybrid new gate realization in all-optical domain. Simulation results verify the functionality of the gate as well as reversibility. Approximate insertion power loss in dB is also reported for the Gaussian incident and control pulse.

  9. Developmental and individual differences in conditional reasoning: effects of logic instructions and alternative antecedents.

    Science.gov (United States)

    Daniel, David B; Klaczynski, Paul A

    2006-01-01

    In Study 1, 10-, 13-, and 16-year-olds were assigned to conditions in which they were instructed to think logically and provided alternative antecedents to the consequents of conditional statements. Providing alternatives improved reasoning on two uncertain logical forms, but decreased logical responding on two certain forms; logic instructions improved reasoning among adolescents. Correlations among inferences and verbal ability were found primarily when task conditions created conflict between automatic and controlled inferences. In Study 2, when the cognitive demands of the logic instructions were reduced, 10-year-olds made more logically correct inferences, but only when a conditional's consequents were strongly associated with alternative antecedents. Discussion focuses on the ability to inhibit invited inferences and the role of automatically activated memories.

  10. Semiconductor optical amplifier-based all-optical gates for high-speed optical processing

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    2000-01-01

    Semiconductor optical amplifiers are useful building blocks for all-optical gates as wavelength converters and OTDM demultiplexers. The paper reviews the progress from simple gates using cross-gain modulation and four-wave mixing to the integrated interferometric gates using cross-phase modulation....... These gates are very efficient for high-speed signal processing and open up interesting new areas, such as all-optical regeneration and high-speed all-optical logic functions...

  11. Semiconductor devices for all-optical regeneration

    DEFF Research Database (Denmark)

    Öhman, Filip; Bischoff, Svend; Tromborg, Bjarne

    2003-01-01

    We review different implementations of semiconductor devices for all-optical regeneration. A general model will be presented for all-optical regeneration in fiber links, taking into consideration the trade-off between non-linearity and noise. Furthermore we discuss a novel regenerator type, based...

  12. All-optical high performance graphene-photonic crystal switch

    Science.gov (United States)

    Hoseini, Mehrdad; Malekmohammad, Mohammad

    2017-01-01

    The all-optical switch is realized based on nonlinear transmission changes in Fano resonance of 2D photonic crystals (PhC) which enhances the light intensity on the graphene in PhC; and in this study, the graphene layer is used as the nonlinear material. The refractive index change of graphene layer leads to a shift in the Fano resonance frequency due to the input light intensity through the Kerr nonlinear effect. Through finite-difference time-domain simulation, it is found that the high performance of all-optical switching can be achieved by the designed structure with a threshold pump intensity as low as MW/cm2. This structure is featured by optical bistability. The obtained results are applicable in micro optical integrated circuits for modulators, switches and logic elements for optical computation.

  13. Experimental study on all-optical half-adder based on semi-conductor optical amplifier

    Institute of Scientific and Technical Information of China (English)

    HAN Bing-chen; YU Jin-long; WANG Wen-rui; ZHANG Li-tai; HU Hao; YANG En-ze

    2009-01-01

    We demonstrate a novel all-optical half-adder based on two semiconductor optical amplifiers (SOAS). Two optical band-pass filters are used to select the two idlers generated by four-wave mixing (FWM) effect of the first SOA. Therefore, the AND gate and XNOR logic are realized simultaneously. The second SOA acts as a NOT gate, in which the NOR logic is achieved with the input of the logic XNOR. As a result, the output is the sum of the two input bits and the carry. In the experiment, all-optical half-addition calculation is achieved between two 10 Gb/s signals.

  14. 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 ...

  15. Micro-fabricated all optical pressure sensors

    DEFF Research Database (Denmark)

    Havreland, Andreas Spandet; Petersen, Søren Dahl; Østergaard, Christian

    2017-01-01

    Optical pressure sensors can operate in certain harsh application areas where the electrical pressure sensors cannot. However, the sensitivity is often not as good for the optical sensors. This work presents an all optical pressure sensor, which is fabricated by micro fabrication techniques, wher...

  16. All-optical tunable photonic crystal cavity

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Ou, Haiyan;

    2010-01-01

    We demonstrate an ultra-small photonic crystal cavity with two resonant modes. An all-optical tuning operation based on the free-carrier plasma effect is, for the first time, realized utilizing a continuous wave light source. The termo-optical effect is minimized by isoproponal infiltration...... of the photonic crystal structure....

  17. 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.

  18. All-optical vector atomic magnetometer.

    Science.gov (United States)

    Patton, B; Zhivun, E; Hovde, D C; Budker, D

    2014-07-04

    We demonstrate an all-optical magnetometer capable of measuring the magnitude and direction of a magnetic field using nonlinear magneto-optical rotation in cesium vapor. Vector capability is added by effective modulation of the field along orthogonal axes and subsequent demodulation of the magnetic-resonance frequency. This modulation is provided by the ac Stark shift induced by circularly polarized laser beams. The sensor exhibits a demonstrated rms noise floor of ∼65  fT/√[Hz] in measurement of the field magnitude and 0.5  mrad/√[Hz] in the field direction; elimination of technical noise would improve these sensitivities to 12  fT/√[Hz] and 10  μrad/√[Hz], respectively. Applications for this all-optical vector magnetometer would include magnetically sensitive fundamental physics experiments, such as the search for a permanent electric dipole moment of the neutron.

  19. All-optical signal processing and regeneration

    DEFF Research Database (Denmark)

    Wolfson, David

    2001-01-01

    components. The objective of this thesis is therefore to present an ivestigation and evaluation fo key components that will be important enablers for future optical networks, namely optical space switches, wavelength converters and regenerators. The focus in the present work is on semiconductor optical...... amplifier (SOA)-based devices. The thesis starts out by giving a description of the motivations and driving forces for the current evolution of optical networks from point-to-point systems to all-otpical network topologies. The use of SOA-based devices for all-optical gating is investigated with the use...... is beneficial to improve the performance. Moreover, issues concerning counter-directional coupling are discussed and advantages and disadvantages of the scheme are highlighted. A scheme, that can be used as a part of all-optical re-timing, is also investigated. The scheme has some advantages compared...

  20. Predictive Condition Monitoring of Induction Motor Bearing Using Fuzzy Logic

    OpenAIRE

    2012-01-01

    Induction motor is critical component in industrial processes and is frequently integrated in commercially available equipment. Safety, reliability, efficiency and performance are the major concerns of induction motor applications. Due to high reliability requirements and cost of breakdown, condition monitoring, diagnosis and Protection increasing importance. Protection of an induction motor (IM) against possible problems, such as stator faults, rotor faults and mechanical faults, occurring i...

  1. All-Optical Network Subsystems Using Integrated SOA-Based Optical Gates and Flip-Flops for Label-Swapped Netorks

    DEFF Research Database (Denmark)

    Seoane, Jorge; Holm-Nielsen, Pablo Villanueva; Kehayas, E.;

    2006-01-01

    In this letter, we demonstrate that all-optical network subsystems, offering intelligence in the optical layer, can be constructed by functional integration of integrated all-optical logic gates and flip-flops. In this context, we show 10-Gb/s all-optical 2-bit label address recognition by interc...

  2. Photonic processing and realization of an all-optical digital comparator based on semiconductor optical amplifiers

    Science.gov (United States)

    Singh, Simranjit; Kaur, Ramandeep; Kaler, Rajinder Singh

    2015-01-01

    A module of an all-optical 2-bit comparator is analyzed and implemented using semiconductor optical amplifiers (SOAs). By employing SOA-based cross phase modulation, the optical XNOR logic is used to get an A=B output signal, where as AB¯ and A¯B> logics operations are used to realize A>B and Aoptical high speed networks and computing systems.

  3. A Simple Fuzzy Logic Approach for Induction Motors Stator Condition Monitoring

    Directory of Open Access Journals (Sweden)

    M. Zeraoulia

    2005-03-01

    Full Text Available Many researches dealt with the problem of induction motors fault detection and diagnosis. The major difficulty is the lack of an accurate model that describes a fault motor. Moreover, experienced engineers are often required to interpret measurement data that are frequently inconclusive. A fuzzy logic approach may help to diagnose induction motor faults. In fact, fuzzy logic is reminiscent of human thinking processes and natural language enabling decisions to be made based on vague information. Therefore, this paper applies fuzzy logic to induction motors fault detection and diagnosis. The motor condition is described using linguistic variables. Fuzzy subsets and the corresponding membership functions describe stator current amplitudes. A knowledge base, comprising rule and data bases, is built to support the fuzzy inference. The induction motor condition is diagnosed using a compositional rule of fuzzy inference.

  4. Digitally encoded all-optical sensor multiplexing

    Science.gov (United States)

    Pervez, Anjum

    1992-01-01

    A digital, all-optical temperature sensor design concept based on optical sampling and digital encoding is presented. The proposed sensor generates 2M binary digital codewords of length M bits. The codewords are generated serially and, therefore, only a single output fiber line is required. A multiplexing scheme, which minimizes the power requirement per sensor array and facilitates a cost-effective digit regeneration for remote monitoring over long distance, is presented. The sensor arrays are used as building blocks to configure large scale sensor networks based on LAN topologies.

  5. All optical binary delta-sigma modulator

    Science.gov (United States)

    Sayeh, Mohammad R.; Siahmakoun, Azad

    2005-09-01

    This paper describes a novel A/D converter called "Binary Delta-Sigma Modulator" (BDSM) which operates only with nonnegative signal with positive feedback and binary threshold. This important modification to the conventional delta-sigma modulator makes the high-speed (>100GHz) all-optical implementation possible. It has also the capability to modify its own sampling frequency as well as its input dynamic range. This adaptive feature helps designers to optimize the system performance under highly noisy environment and also manage the power consumption of the A/D converters.

  6. All-optical OFDM network coding scheme for all-optical virtual private communication in PON

    Science.gov (United States)

    Li, Lijun; Gu, Rentao; Ji, Yuefeng; Bai, Lin; Huang, Zhitong

    2014-03-01

    A novel optical orthogonal frequency division multiplexing (OFDM) network coding scheme is proposed over passive optical network (PON) system. The proposed scheme for all-optical virtual private network (VPN) does not only improve transmission efficiency, but also realize full-duplex communication mode in a single fiber. Compared with the traditional all-optical VPN architectures, the all-optical OFDM network coding scheme can support higher speed, more flexible bandwidth allocation, and higher spectrum efficiency. In order to reduce the difficulty of alignment for encoding operation between inter-communication traffic, the width of OFDM subcarrier pulse is stretched in our proposed scheme. The feasibility of all-optical OFDM network coding scheme for VPN is verified, and the relevant simulation results show that the full-duplex inter-communication traffic stream can be transmitted successfully. Furthermore, the tolerance of misalignment existing in inter-ONUs traffic is investigated and analyzed for all-optical encoding operation, and the difficulty of pulse alignment is proved to be lower.

  7. All-optical bandwidth-tailorable radar

    CERN Document Server

    Zou, Weiwen; Long, Xin; Zhang, Siteng; Cui, Yuanjun; Chen, Jianping

    2015-01-01

    Radar has been widely used in military, security, and rescue. Metamaterial cloak is employed in stealth targets to evade radar detection. Hence modern radar should be reconfigurable at multi-bands for detecting stealth targets, which might be realized based on microwave photonics. Here, we demonstrate an all-optical bandwidth-tailorable radar architecture. It is a coherent system utilizing one mode-locked laser for both signal generation and reception. Heterodyning of two individually filtered optical pulses that are pre-chirped via wavelength-to-time mapping generates wideband linearly-chirped radar signal. The working bands can be flexibly tailored with desired bandwidth at user-preferred carrier frequency. After modulated onto the pre-chirped optical pulse, radar echoes are time-stretched and frequency-compressed by several times. The digitization becomes much easier without loss of detection ability. We believe that the demonstration can innovate the radar's architecture with ultra-high range resolution.

  8. ALL OPTICAL IMPLEMENTATION OF HIGH SPEED AND LOW POWER REVERSIBLE FULL ADDER USING SEMICONDUCTOR OPTICAL AMPLIFIER BASED MACH-ZEHNDER INTERFEROMETER

    Directory of Open Access Journals (Sweden)

    R. M. Bommi

    2014-01-01

    Full Text Available In the recent years reversible logic design has promising applications in low power computing, optical computing, quantum computing. VLSI design mainly concentrates on low power logic circuit design. In the present scenario researchers have made implementations of reversible logic gates in optical domain for its low energy consumption and high speed. This study is all about designing a reversible Full adder using combination of all optical Toffoli and all optical TNOR and to compare it with the Full adder designed using all optical Toffoli gate in terms of optical cost. All optical TNOR gate can work as a replacement of existing NAND based All optical Toffoli Gate (TG. The gates are designed using Mach-Zehnder Interferometer (MZI based optical switch. The proposed system is developed with the basic of reversibility to design all optical full Adder implemented with CMOS transistors. The design is efficient in terms of both architecture and in power consumption.

  9. 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.

  10. The GALAXIE all-optical FEL project

    Energy Technology Data Exchange (ETDEWEB)

    Rosenzweig, J. B.; Arab, E.; Andonian, G.; Cahill, A.; Fitzmorris, K.; Fukusawa, A.; Hoang, P.; Jovanovic, I.; Marcus, G.; Marinelli, A.; Murokh, A.; Musumeci, P.; Naranjo, B.; O' Shea, B.; O' Shea, F.; Ovodenko, A.; Pogorelsky, I.; Putterman, S.; Roberts, K.; Shumail, M. [Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States); Dept. of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA 16802 (United States); Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States); and others

    2012-12-21

    We describe a comprehensive project, funded under the DARPA AXiS program, to develop an all-optical table-top X-ray FEL based on dielectric acceleration and electromagnetic undulators, yielding a compact source of coherent X-rays for medical and related applications. The compactness of this source demands that high field (>GV/m) acceleration and undulation-inducing fields be employed, thus giving rise to the project's acronym: GV/m AcceLerator And X-ray Integrated Experiment (GALAXIE). There are numerous physics and technical hurdles to surmount in this ambitious scenario, and the integrated solutions include: a biharmonic photonic TW structure, 200 micron wavelength electromagnetic undulators, 5 {mu}m laser development, ultra-high brightness magnetized/asymmetric emittance electron beam generation, and SASE FEL operation. We describe the overall design philosophy of the project, the innovative approaches to addressing the challenges presented by the design, and the significant progress towards realization of these approaches in the nine months since project initialization.

  11. All-Optical Generation of Surface Plasmons in Graphene

    CERN Document Server

    Constant, Thomas J; Chang, Darrick E; Hendry, Euan

    2015-01-01

    Here we present an all-optical plasmon coupling scheme, utilising the intrinsic nonlinear optical response of graphene. We demonstrate coupling of free-space, visible light pulses to the surface plasmons in a planar, un-patterned graphene sheet by using nonlinear wave mixing to match both the wavevector and energy of the surface wave. By carefully controlling the phase-matching conditions, we show that one can excite surface plasmons with a defined wavevector and direction across a large frequency range, with an estimated photon efficiency in our experiments approaching $10^{-5}$.

  12. 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...

  13. Use of fuzzy logic for condition monitoring of motor driven machineries

    Science.gov (United States)

    Janier, Josefina Barnachea; Zaim Zaharia, M. Fazrin

    2012-06-01

    An intelligent system called Fuzzy Logic is one of the current technologies that allow a description of the desired system behavior using common language. It generalizes the yes-no Boolean logic into numerical value of 1 and 0 but also permits the in between values. This paper presents the use of Fuzzy Logic to determine the unusual increase of vibrations of an induction motor called vibration analysis. Sudden increase of vibrations could be a good indicator of faulty condition of the motor. Based on the vibration characteristics of the motor, a Fuzzy Inference System (FIS) was created. The system classified the motor of the gas distribution pump as `acceptable' of the vibration ranges from 1.8mm/s to 4.5mm/s or `monitor closely' of the vibration ranges from 4.5mm/s to 7.1mm/s respectively. The system enabled an early detection of faults which is very important in maintenance management.

  14. An all-optical method of developing data communication system with error detection circuit

    Science.gov (United States)

    Mandal, Sumana; Mandal, Dhoumendra; Garai, Sisir Kumar

    2014-03-01

    The basic criterion of data communication is that received data should exactly be the replica of the transmitting data. If any error is introduced in the received data, then data transmission should be stopped immediately. In this article the authors have developed an all-optical method of data communication system with error detection mechanism that works with frequency encoded data. Basic building blocks of the proposed data communication scheme are parity generator and parity checker which are developed from all optical XOR logic gates. Simulation results testify the feasibility of the proposed scheme. These logic gates are developed exploiting nonlinear polarization rotation based frequency conversion and switching character of semiconductor optical amplifiers. The scheme with frequency encoded data, high speed of frequency conversion and polarization switching action of semiconductor optical amplifier offers secure, error free, faster data communication network.

  15. All-optical NOR gate based on injection-locking effect in a semiconductor laser

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A scheme for all-optical NOR logic gate is proposed based on injection-locking effect in a semiconductor laser. In this scheme, signal light injection into the laser will cause frequency shift of laser modes, as a result, the probe light into the laser can be switched between injection-locked and unlocked status, and its output power will be modulated. Theoretical analysis for this scheme is carried out by using a model to describe the dynamics of the injection-locked laser. By numerical simulation, the influence of laser bias current, laser length, injected signal power and signal frequency on the output performance of NOR logic gate is quantitatively analyzed.

  16. The effect of emotion on interpretation and logic in a conditional reasoning task.

    Science.gov (United States)

    Blanchette, Isabelle

    2006-07-01

    The effect of emotional content on logical reasoning is explored in three experiments. Theparticipants completed a conditional reasoning task (If p, then q) with emotional and neutral contents. In Experiment 1, existing emotional and neutral words were used. The emotional value of initially neutral words was experimentally manipulated in Experiments 1B and 2, using classical conditioning. In all experiments, participants were less likely to provide normatively correct answers when reasoning about emotional stimuli, compared with neutral stimuli. This was true for both negative (Experiments 1B and 2) and positive contents (Experiment 2). The participants' interpretations of the conditional statements were also measured (perceived sufficiency, necessity, causality, and plausibility). The results showed the expected relationship between interpretation and reasoning. However, emotion did not affect interpretation. Emotional and neutral conditional statements were interpreted similarly. The results are discussed in light of current models of emotion and reasoning.

  17. Management of air-conditioning systems in residential buildings by using fuzzy logic

    Directory of Open Access Journals (Sweden)

    Sohair F. Rezeka

    2015-06-01

    Full Text Available There has been a rising concern in reducing the energy consumption in buildings. Heating, ventilation and air-conditioning system is the biggest consumer of energy in buildings. In this study, management of the air-conditioning system of a building for efficient energy operation and comfortable environment is investigated. The strategy used in this work depends on classifying the rooms to three different groups: very important rooms, important rooms and normal rooms. The total mass flow rate is divided between all rooms by certain percentage using a fuzzy-logic system to get the optimum performance for each room. The suggested Building Management System (BMS was found capable of keeping errors in both temperature and humidity within the acceptable limits at different operating conditions. The BMS can save the chilled/hot water flow rate and the cooling/heating capacity of rooms.

  18. Characterisation of hybrid integrated all-optical flip-flop

    DEFF Research Database (Denmark)

    Liu, Y.; McDougall, R.; Seoane, Jorge

    2006-01-01

    We present a fully-packaged, hybrid-integrated all-optical flip-flop with separate optical set and reset operation. The flip-flop can control a wavelength converter to route 40 Gb/s data packets all-optically. The experimental results are given.......We present a fully-packaged, hybrid-integrated all-optical flip-flop with separate optical set and reset operation. The flip-flop can control a wavelength converter to route 40 Gb/s data packets all-optically. The experimental results are given....

  19. State-selective all-optical detection of Rydberg atoms

    CERN Document Server

    Karlewski, Florian; Grimmel, Jens; Sándor, Nóra; Fortágh, and József

    2015-01-01

    We present an all-optical protocol for detecting population in a selected Rydberg state of alkali atoms. The detection scheme is based on the interaction of an ensemble of ultracold atoms with two laser pulses: one weak probe pulse which is resonant with the transition between the ground state and the first excited state, and a pulse with high intensity which couples the first excited state to the selected Rydberg state. We show that by monitoring the absorption signal of the probe laser over time, one can deduce the initial population of the Rydberg state. Furthermore, it is shown that - for suitable experimental conditions - the dynamical absorption curve contains information on the initial coherence between the ground state and the selected Rydberg state. We present the results of a proof-of-principle measurement performed on a cold gas of $^{87}$Rb atoms. The method is expected to find application in quantum computing protocols based on Rydberg atoms.

  20. All-optical generation of surface plasmons in graphene

    Science.gov (United States)

    Constant, T. J.; Hornett, S. M.; Chang, D. E.; Hendry, E.

    2016-02-01

    Surface plasmons in graphene offer a compelling route to many useful photonic technologies. As a plasmonic material, graphene offers several intriguing properties, such as excellent electro-optic tunability, crystalline stability, large optical nonlinearities and extremely high electromagnetic field concentration. As such, recent demonstrations of surface plasmon excitation in graphene using near-field scattering of infrared light have received intense interest. Here we present an all-optical plasmon coupling scheme which takes advantage of the intrinsic nonlinear optical response of graphene. Free-space, visible light pulses are used to generate surface plasmons in a planar graphene sheet using difference frequency wave mixing to match both the wavevector and energy of the surface wave. By carefully controlling the phase matching conditions, we show that one can excite surface plasmons with a defined wavevector and direction across a large frequency range, with an estimated photon efficiency in our experiments approaching 10-5.

  1. Ring-based All-Optical Datacenter Networks

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Berger, Michael Stübert; Ruepp, Sarah Renée

    2015-01-01

    Ring-based generic network architecture for all-optical datacenters is proposed, offering highly scalable interconnection network with reduced cabling complexity. Simulations show improved performance compared to all-optical fat-tree datacenter architecture with 40%-99% improved connection request...

  2. Reconfigurable all-optical dual-directional half-subtractor for high-speed differential phase shift keying signal based on semiconductor optical amplifiers

    Institute of Scientific and Technical Information of China (English)

    Zhang Yin; Dong Jian-Ji; Lei Lei; Zhang Xin-Liang

    2012-01-01

    All-optical digital logic elementary circuits are the building blocks of many important computational operations in future high-speed all-optical networks and computing systems.Multifunctional and reconfigurable logic units are essential in this respect.Employing the demodulation properties of delay interferometers for input differential phase shift keying signals and the gain saturation effect in two parallel semiconductor optical amplifiers,a novel design of 40 Gbit/s reconfigurable all-optical dual-directional half-subtractor is proposed and demonstrated.All output logic results show that the scheme achieves over 11=dB extinction ratio,clear and wide open eye diagram,as well as low polarization dependence (< 1 dB),without using any additional input light beam.The scheme may provide a promising candidate for future ultrafast all-optical signal processing applications.

  3. All-optical repetition rate multiplication of pseudorandom bit sequences based on cascaded TOADs

    Science.gov (United States)

    Sun, Zhenchao; Wang, Zhi; Wu, Chongqing; Wang, Fu; Li, Qiang

    2016-03-01

    A scheme for all-optical repetition rate multiplication of pseudorandom bit sequences (PRBS) is demonstrated with all-optical wavelength conversion and optical logic gate 'OR' based on cascaded Tera-Hertz Optical Asymmetric Demultiplexers (TOADs). Its feasibility is verified by multiplication experiments from 500 Mb/s to 4 Gb/s for 23-1 PRBS and from 1 Gb/s to 4 Gb/s for 27-1 PRBS. This scheme can be employed for rate multiplication for much longer cycle PRBS at much higher bit rate over 40 Gb/s when the time-delay, the loss and the dispersion of the optical delay line are all precisely managed. The upper limit of bit rate will be restricted by the recovery time of semiconductor optical amplifier (SOA) finally.

  4. Pausing and activating thread state upon pin assertion by external logic monitoring polling loop exit time condition

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dong; Giampapa, Mark; Heidelberger, Philip; Ohmacht, Martin; Satterfield, David L; Steinmacher-Burow, Burkhard; Sugavanam, Krishnan

    2013-05-21

    A system and method for enhancing performance of a computer which includes a computer system including a data storage device. The computer system includes a program stored in the data storage device and steps of the program are executed by a processer. The processor processes instructions from the program. A wait state in the processor waits for receiving specified data. A thread in the processor has a pause state wherein the processor waits for specified data. A pin in the processor initiates a return to an active state from the pause state for the thread. A logic circuit is external to the processor, and the logic circuit is configured to detect a specified condition. The pin initiates a return to the active state of the thread when the specified condition is detected using the logic circuit.

  5. Fuzzy logic control of air-conditioning system in residential buildings

    Directory of Open Access Journals (Sweden)

    Abdel-Hamid Attia

    2015-09-01

    Full Text Available There has been a rising concern in reducing the energy consumption in building. Heating ventilation and air condition system is the biggest consumer of energy in building. In this study, fuzzy logic control of the air conditioning system of building for efficient energy operation and comfortable environment is investigated. A theoretical model of the fan coil unit (FCU and the heat transfer between air and coolant fluid is derived. The controlled variables are the room temperature and relative humidity and control consequents are the percentage of chilled and hot water flow rates at summer and the percentage of hot water and steam injected flow rates at winter. A computer simulation has been conducted and fuzzy control results are compared with that of conventional Proportional-Integral-Derivative control. It was found that the proposed control strategy satisfies the space load and at the same time to achieve the comfort zone, as defined by the ASHRAE code. Meanwhile PID control fails to adjust the room temperature at part-load operations. It has been demonstrated that fuzzy controller operation is more efficient and consumes less energy than PID control.

  6. Dynamics of an all-optical atomic spin gyroscope.

    Science.gov (United States)

    Fang, Jiancheng; Wan, Shuangai; Yuan, Heng

    2013-10-20

    We present the transfer function of an all-optical atomic spin gyroscope through a series of differential equations and validate the transfer function by experimental test. A transfer function is the basis for further control system design. We build the differential equations based on a complete set of Bloch equations describing the all-optical atomic spin gyroscope, and obtain the transfer function through application of the Laplace transformation to these differential equations. Moreover, we experimentally validate the transfer function in an all-optical Cs-Xe129 atomic spin gyroscope through a series of step responses. This transfer function is convenient for analysis of the form of control system required. Furthermore, it is available for the design of the control system specifically to improve the performance of all-optical atomic spin gyroscopes.

  7. All-optical gates based on photonic crystal resonators

    Science.gov (United States)

    Moille, Grégory; De Rossi, Alfredo; Combrié, Sylvain

    2016-04-01

    We briefly review the technology of advanced nonlinear resonators for all-optical gating with a specific focus on the application of high-performance signal sampling and on the properties of III-V semiconductor photonic crystals

  8. All-optical signal processing using dynamic Brillouin gratings

    Science.gov (United States)

    Santagiustina, Marco; Chin, Sanghoon; Primerov, Nicolay; Ursini, Leonora; Thévenaz, Luc

    2013-01-01

    The manipulation of dynamic Brillouin gratings in optical fibers is demonstrated to be an extremely flexible technique to achieve, with a single experimental setup, several all-optical signal processing functions. In particular, all-optical time differentiation, time integration and true time reversal are theoretically predicted, and then numerically and experimentally demonstrated. The technique can be exploited to process both photonic and ultra-wide band microwave signals, so enabling many applications in photonics and in radio science. PMID:23549159

  9. 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

  10. All-optical sampling OFDM system performance analysis

    Institute of Scientific and Technical Information of China (English)

    Hang Ye; Hongwei Chen; Chao Tang; Minghua Chen; Shizhong Xie

    2011-01-01

    The performance of a novel all-optical sampling orthogonal frequency division multiplexing (OFDM) system is proposed and analyzed. Time delays and phase shifters are used to realize all optical forward/inverse discrete Fourier transform (DFT/IDFT). Different system configurations are tested and analyzed to optimize the performance, including the system capacity, modulation formats, DFT/IDFT constructions,and the width of the sample pulse. The 50- and 100-Gb/s real-time all-optical sampling (AOS) OFDM systems are investigated. All results are analyzed, and useful suggestions are offered for future high-speed applications.%@@ The performance of a novel all-optical sampling orthogonal frequency division multiplexing (OFDM) system is proposed and analyzed. Time delays and phase shifters are used to realize all optical forward/inverse discrete Fourier transform (DFT/IDFT). Different system configurations are tested and analyzed to optimize the performance, including the system capacity, modulation formats, DFT/IDFT constructions,and the width of the sample pulse. The 50-and 100-Gb/s real-time all-optical sampling (AOS) OFDM systems are investigated. All results are analyzed, and useful suggestions are offered for future high-speed applications.

  11. Ultrafast all-optical NOR gate based on semiconductor optical amplifier and fiber delay interferometer

    Science.gov (United States)

    Xu, Jing; Zhang, Xinliang; Liu, Deming; Huang, Dexiu

    2006-10-01

    An ultrafast all-optical logic NOR gate based on a semiconductor optical amplifier (SOA) and a fiber delay interferometer (FDI) is presented. For high-speed input return-to-zero (RZ) signal, nonreturn-to-zero (NRZ) switching windows which satisfy Boolean NOR operation can be formed by properly choosing the delay time and the phase shift of FDI. 40Gb/s NOR operation has been demonstrated successfully with low control optical power. The factors that degrade the NOR operation have been discussed.

  12. All-optical signal processing technique for secure optical communication

    Science.gov (United States)

    Qian, Feng-chen; Su, Bing; Ye, Ya-lin; Zhang, Qian; Lin, Shao-feng; Duan, Tao; Duan, Jie

    2015-10-01

    Secure optical communication technologies are important means to solve the physical layer security for optical network. We present a scheme of secure optical communication system by all-optical signal processing technique. The scheme consists of three parts, as all-optical signal processing unit, optical key sequence generator, and synchronous control unit. In the paper, all-optical signal processing method is key technology using all-optical exclusive disjunction (XOR) gate based on optical cross-gain modulation effect, has advantages of wide dynamic range of input optical signal, simple structure and so on. All-optical XOR gate composed of two semiconductor optical amplifiers (SOA) is a symmetrical structure. By controlling injection current, input signal power, delay and filter bandwidth, the extinction ratio of XOR can be greater than 8dB. Finally, some performance parameters are calculated and the results are analyzed. The simulation and experimental results show that the proposed method can be achieved over 10Gbps optical signal encryption and decryption, which is simple, easy to implement, and error-free diffusion.

  13. All-Optical Half-Adder Using All-Optical XOR and AND Gates for Optical Generation of "Sum" and "Carry"

    Science.gov (United States)

    Menezes, J. W. M.; Fraga, W. B.; Ferreira, A. C.; Guimarães, G. F.; Filho, A. F. G. F.; Sobrinho, C. S.; Sombra, A. S. B.

    2010-07-01

    In this article, a numerical simulation study using the symmetric planar three-core non-linear directional coupler, operating with a short light pulse (2 ps), for the implementation of an all-optical half-adder is presented. The half-adder is the key building block for many digital processing functions such as shift register, binary counter, and serial parallel data converters. Optical couplers are an important component for application in optical fiber telecommunication systems and all integrated optical circuits because of very high switching speeds (as high as the femto-second range). In this numerical simulation, the symmetric planar three-core non-linear directional coupler presents a planar symmetrical structure with three cores in a parallel equidistant arrangement, three logical inputs (CP, A, and B), and two output logic functions (C and S). The CP(ΔΦ) input is a control pulse with a phase difference ΔΦ = Δθπ (0 ≤ Δθ ≤ 2) between inputs A and B (logical inputs of the half-adder) and one amplitude discriminator circuit. The half-adder uses two output logic functions of Sum(S) and Carry(C), which can be demonstrated by using XOR and AND gates, respectively. For the half-adder, the phase [ΔΦMIN, ΔΦMAX] intervals are studied, allowing the operation of the device as a half-adder. For the selected range of CP(ΔΦBETTER), the extinction ratio was studied, the compression factors for both Sum(S) and Carry(C) outputs of the symmetric planar three-core non-linear directional coupler.

  14. All-optical information processing in photonic crystals

    Science.gov (United States)

    Yanik, Mehmet Fatih

    This thesis covers coherent and incoherent all-optical information processing using photonic bandgap nanostructures and microcavities. The first 3 chapters introduce all-optical bistable switching, transistor and memory elements with sub-micron scale dimensions. A strategy for large scale integration without optical isolators is also described. In chapters 4 and 5, dynamically modulated photonic crystal structures are introduced. It is shown that light pulses can be stopped and stored all-optically without requiring any coherent or resonant light-matter interaction. In chapter 6, it is shown that light pulses can be coherently time-reversed by using only index modulations and linear optics. In chapter 7, a supercomputer implementation of an object oriented finite difference time domain simulation is described to simulate photonic nanostructures with arbitrary material & geometric features.

  15. High contrast all-optical diode based on direction-dependent optical bistability within asymmetric ring cavity

    Science.gov (United States)

    Xia, Xiu-Wen; Zhang, Xin-Qin; Xu, Jing-Ping; Yang, Ya-Ping

    2016-08-01

    We propose a simple all-optical diode which is comprised of an asymmetric ring cavity containing a two-level atomic ensemble. Attributed to spatial symmetry breaking of the ring cavity, direction-dependent optical bistability is obtained in a classical bistable system. Therefore, a giant optical non-reciprocity is generated, which guarantees an all-optical diode with a high contrast up to 22 dB. Furthermore, its application as an all-optical logic AND gate is also discussed. Project supported by the National Natural Science Foundation of China (Grant Nos. 11274242, 11474221, and 11574229), the Joint Fund of the National Natural Science Foundation of China and the China Academy of Engineering Physics (Grant No. U1330203), and the National Key Basic Research Special Foundation of China (Grant Nos. 2011CB922203 and 2013CB632701).

  16. All-optical, Three-axis Fiber Laser Magnetometer

    Science.gov (United States)

    2012-04-16

    E-1 1.  INTRODUCTION ...achieved with other magnetic field sensing technologies such as those based on flux gates and fiber optic magnetostrictive sensors. The deployed...ALL-OPTICAL, THREE-AXIS FIBER LASER MAGNETOMETER 1. INTRODUCTION This report describes the development of an undersea fiber optic magnetometer

  17. All-optical orthogonal frequency division multiplexing (OFDM) transmitter

    DEFF Research Database (Denmark)

    2015-01-01

    The invention relates to an all-optical orthogonal frequency division multiplexing (OFDM) transmitter for generating an OFDM output signal. The transmitter comprises a first time-domain optical Fourier transform (OFT) assembly, the first OFT assembly is of a K-D-K configuration and comprises...

  18. All-optical demultiplexing using an electroabsorption modulator

    DEFF Research Database (Denmark)

    Højfeldt, Sune; Bischoff, Svend; Mørk, Jesper

    2000-01-01

    In the 1990s, the electroabsorption modulator (EAM) has found a wide range of applications. Functionalities such as pulse generation and demultiplexing by electrical modulation have been demonstrated using an EAM. Recently, all-optical wavelength conversion, demultiplexing, and signal regeneration...

  19. Plasmonic enhancement of ultrafast all-optical magnetization reversal

    Science.gov (United States)

    Kochergin, Vladimir; Neely, Lauren N.; Allin, Leigh J.; Kochergin, Eugene V.; Wang, Kang L.

    2011-10-01

    Ultrafast all optical magnetization switching in GdFeCo layers on the basis of Inverse Faraday Effect (IFE) was demonstrated recently and suggested as a possible path toward next generation magnetic data storage medium with much faster writing time. However, to date, the demonstrations of ultrafast all-optical magnetization switching were performed with powerful femtosecond lasers, hardly useful for practical applications in data storage and data processing. Here we show that utilization of IFE enhancement in plasmonic nanostructures enables fast all-optical magnetization switching with smaller/cheaper laser sources with longer pulse durations. Our modeling results predict significant enhancement of IFE around all major types of plasmonic nanostructures for a circularly polarized incident light. Unlike the IFE in uniform bulk materials, nonzero value of IFE is predicted in plasmonic nanostructures even with a linearly polarized excitation. Experimentally, all-optical magnetization switching at 20 times lower laser fluence and roughly 100 times lower value of laser fluence/pulse duration ratio is demonstrated in plasmonic samples to verify the model predictions. The path to achieve higher levels of enhancement experimentally is discussed.

  20. A Novel All-Optical Analog-to-Digital Converter

    Institute of Scientific and Technical Information of China (English)

    Xiaobo; Hou; Afshin; Daryoush; Warren; Rosen

    2003-01-01

    An all-optical analog-to-digital converter capable of sampling at 50GS/s is described. The ADC works in the frequency domain. The RF signal is sampled by electro-optically steerable gratings and quantized by a set of detectors with scalable apertures.

  1. A Novel Strain-Based Method to Estimate Tire Conditions Using Fuzzy Logic for Intelligent Tires.

    Science.gov (United States)

    Garcia-Pozuelo, Daniel; Olatunbosun, Oluremi; Yunta, Jorge; Yang, Xiaoguang; Diaz, Vicente

    2017-02-10

    The so-called intelligent tires are one of the most promising research fields for automotive engineers. These tires are equipped with sensors which provide information about vehicle dynamics. Up to now, the commercial intelligent tires only provide information about inflation pressure and their contribution to stability control systems is currently very limited. Nowadays one of the major problems for intelligent tire development is how to embed feasible and low cost sensors to obtain reliable information such as inflation pressure, vertical load or rolling speed. These parameters provide key information for vehicle dynamics characterization. In this paper, we propose a novel algorithm based on fuzzy logic to estimate the mentioned parameters by means of a single strain-based system. Experimental tests have been carried out in order to prove the suitability and durability of the proposed on-board strain sensor system, as well as its low cost advantages, and the accuracy of the obtained estimations by means of fuzzy logic.

  2. All-optical phase modulation for integrated interferometric biosensors.

    Science.gov (United States)

    Dante, Stefania; Duval, Daphné; Sepúlveda, Borja; González-Guerrero, Ana Belen; Sendra, José Ramón; Lechuga, Laura M

    2012-03-26

    We present the theoretical and the experimental implementation of an all-optical phase modulation system in integrated Mach-Zehnder Interferometers to solve the drawbacks related to the periodic nature of the interferometric signal. Sensor phase is tuned by modulating the emission wavelength of low-cost commercial laser diodes by changing their output power. FFT deconvolution of the signal allows for direct phase readout, immune to sensitivity variations and to light intensity fluctuations. This simple phase modulation scheme increases the signal-to-noise ratio of the measurements in one order of magnitude, rendering in a sensor with a detection limit of 1.9·10⁻⁷ RIU. The viability of the all-optical modulation approach is demonstrated with an immunoassay detection as a biosensing proof of concept.

  3. Optimised Design and Analysis of All-Optical Networks

    DEFF Research Database (Denmark)

    Glenstrup, Arne John

    2002-01-01

    level is presented. The method uses an unorthodox routing strategy focusing on common subpaths rather than individual connections, and strives to minimise switch port count as well as fibre usage. It is shown to produce cheaper network designs than previous methods when fibre costs are comparatively...... is developed, based on shortest-path algorithms and a comparatively new metaheuristic called simulated allocation. It is able to handle design of all-optical mesh networks with optical cross-connects, considers duct as well as fibre and node costs, and can also design protected networks. The method is assessed...... through various experiments and is shown to produce good results and to be able to scale up to networks of realistic sizes. A novel method, subpath wavelength grouping, for routing connections in a multigranular all-optical network where several wavelengths can be grouped and switched at band and fibre...

  4. All-Optical Field-Induced Second-Harmonic Generation

    CERN Document Server

    Davidson, Roderick B; Ziegler, Jed I; Avanesyan, Sergey M; Lawrie, Ben J; Haglund, Richard F

    2015-01-01

    Efficient frequency modulation techniques are crucial to the development of plasmonic metasurfaces for information processing and energy conversion. Nanoscale electric-field confinement in optically pumped plasmonic structures enables stronger nonlinear susceptibilities than are attainable in bulk materials. The interaction of three distinct electric fields in (chi)^3 optical processes allows for all-optical modulation of nonlinear signals. Here we demonstrate effcient third-order second harmonic generation (SHG) in a serrated nanogap plasmonic geometry that generates steep electric field gradients within a dielectric material. We utilize an ultrafast optical pump to control the plasmonically induced electric-fields and to generate bandwidth-limited ultrafast second-harmonic pulses driven by the control pulses. The combination of plasmonic metasurfaces with all-optical control and the freedom to choose the dielectric allow multiple generalizations of this concept and geometry to other four-wave mixing process...

  5. 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.

  6. All-optical mode unscrambling on a silicon photonic chip

    CERN Document Server

    Morichetti, Francesco; Grillanda, Stefano; Peserico, Nicola; Carminati, Marco; Ciccarella, Pietro; Ferrari, Giorgio; Guglielmi, Emanuele; Sorel, Marc; Melloni, Andrea

    2015-01-01

    We demonstrate a 4-channel silicon photonic MIMO demultiplexer performing all-optical unscrambling of four mixed modes. Mode unscrambling is achieved by means of a cascaded Mach-Zehnder architecture that is sequentially reconfigured by individually monitoring each stage though integrated transparent detectors, namely Contact Less Integrated Photonic Probes (CLIPPs). Robust demultiplexing of 10 Gbit/s channels with less than -20 dB crosstalk is achieved.

  7. Nonlinear fiber applications for ultrafast all-optical signal processing

    Science.gov (United States)

    Kravtsov, Konstantin

    In the present dissertation different aspects of all-optical signal processing, enabled by the use of nonlinear fibers, are studied. In particular, we focus on applications of a novel heavily GeO2-doped (HD) nonlinear fiber, that appears to be superior to many other types of nonlinear fibers because of its high nonlinearity and suitability for the use in nonlinear optical loop mirrors (NOLMs). Different functions, such as all-optical switching, thresholding, and wavelength conversion, are demonstrated with the HD fibers in the NOLM configuration. These basic functions are later used for realization of ultrafast time-domain demultiplexers, clock recovery, detectors of short pulses in stealth communications, and primitive elements for analog computations. Another important technology that benefits from the use of nonlinear fiber-based signal processing is optical code-division multiple access (CDMA). It is shown in both theory and experiment that all-optical thresholding is a unique way of improving existing detection methods for optical CDMA. Also, it is the way of implementation of true asynchronous optical spread-spectrum networks, which allows full realization of optical CDMA potential. Some aspects of quantum signal processing and manipulation of quantum states are also studied in this work. It is shown that propagation and collisions of Thirring solitons lead to a substantial squeezing of quantum states, which may find applications for generation of squeezed light.

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

    DEFF Research Database (Denmark)

    Nielsen, Mads Lønstrup

    2004-01-01

    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...... switch. Differential -mode switches are shown to eliminate one contribution to the patterning effects, referred to as the linear patterning. This enables operation at bitrates far beyond the limit set by the carrier lifetime, but ultimately a saturation-induced patterning effect, nonlinear patterning...

  9. Simultaneous demonstration on all-optical digital encoder and comparator at 40 Gb/s with semiconductor optical amplifiers.

    Science.gov (United States)

    Wang, Yang; Zhang, Xinliang; Dong, Jianji; Huang, Dexiu

    2007-11-12

    We proposed and experimental demonstrated all-optical two line-four line encoder and two bit-wise comparator of RZ data streams at 40Gb/s based on cross gain modulation (XGM) and four wave mixing (FWM) in three parallel SOAs. Five logic functions for digital encoder and comparator between two signals A and B: AB, AB, AB, AB and AOmicronB, were achieved simultaneously. The first three optical logics are realized based on XGM in SOAs, the fourth is realized with FWM, and the fifth is the mixing result of the first and the fourth. A detuning filter is employed to improve the output performance. The output extinction ratio (ER) for the XGM operation is above 10dB, and the ER for FWM operation is around 8 dB. Wide and clear eye patterns for the five logic outputs can be observed.

  10. A Novel Strain-Based Method to Estimate Tire Conditions Using Fuzzy Logic for Intelligent Tires

    Science.gov (United States)

    Garcia-Pozuelo, Daniel; Olatunbosun, Oluremi; Yunta, Jorge; Yang, Xiaoguang; Diaz, Vicente

    2017-01-01

    The so-called intelligent tires are one of the most promising research fields for automotive engineers. These tires are equipped with sensors which provide information about vehicle dynamics. Up to now, the commercial intelligent tires only provide information about inflation pressure and their contribution to stability control systems is currently very limited. Nowadays one of the major problems for intelligent tire development is how to embed feasible and low cost sensors to obtain reliable information such as inflation pressure, vertical load or rolling speed. These parameters provide key information for vehicle dynamics characterization. In this paper, we propose a novel algorithm based on fuzzy logic to estimate the mentioned parameters by means of a single strain-based system. Experimental tests have been carried out in order to prove the suitability and durability of the proposed on-board strain sensor system, as well as its low cost advantages, and the accuracy of the obtained estimations by means of fuzzy logic. PMID:28208631

  11. A Novel Strain-Based Method to Estimate Tire Conditions Using Fuzzy Logic for Intelligent Tires

    Directory of Open Access Journals (Sweden)

    Daniel Garcia-Pozuelo

    2017-02-01

    Full Text Available The so-called intelligent tires are one of the most promising research fields for automotive engineers. These tires are equipped with sensors which provide information about vehicle dynamics. Up to now, the commercial intelligent tires only provide information about inflation pressure and their contribution to stability control systems is currently very limited. Nowadays one of the major problems for intelligent tire development is how to embed feasible and low cost sensors to obtain reliable information such as inflation pressure, vertical load or rolling speed. These parameters provide key information for vehicle dynamics characterization. In this paper, we propose a novel algorithm based on fuzzy logic to estimate the mentioned parameters by means of a single strain-based system. Experimental tests have been carried out in order to prove the suitability and durability of the proposed on-board strain sensor system, as well as its low cost advantages, and the accuracy of the obtained estimations by means of fuzzy logic.

  12. All-optical photon echo on a chip

    Science.gov (United States)

    Moiseev, E. S.; Moiseev, S. A.

    2017-01-01

    We demonstrate that a photon echo can be implemented by all-optical means using an array of on-chip high-finesse ring cavities whose parameters are chirped in such a way as to support equidistant spectra of cavity modes. When launched into such a system, a classical or quantum optical signal—even a single-photon field—becomes distributed between individual cavities, giving rise to prominent coherence echo revivals at well-defined delay times, controlled by the chirp of cavity parameters. This effect enables long storage times for high-throughput broadband optical delay and quantum memory.

  13. Realization of an all optical exciton-polariton router

    Energy Technology Data Exchange (ETDEWEB)

    Marsault, Félix; Nguyen, Hai Son; Tanese, Dimitrii; Lemaître, Aristide; Galopin, Elisabeth; Sagnes, Isabelle; Amo, Alberto [Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis (France); Bloch, Jacqueline, E-mail: jacqueline.bloch@lpn.cnrs.fr [Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis (France); Physics Department, Ecole Polytechnique, F-91128 Palaiseau Cedex (France)

    2015-11-16

    We report on the experimental realization of an all optical router for exciton-polaritons. This device is based on the design proposed by Flayac and Savenko [Appl. Phys. Lett. 103, 201105 (2013)], in which a zero-dimensional island is connected through tunnel barriers to two periodically modulated wires of different periods. Selective transmission of polaritons injected in the island, into either of the two wires, is achieved by tuning the energy of the island state across the band structure of the modulated wires. We demonstrate routing of ps polariton pulses using an optical control beam which controls the energy of the island quantum states, thanks to polariton-exciton interactions.

  14. Data Logic

    DEFF Research Database (Denmark)

    Nilsson, Jørgen Fischer

    A Gentle introduction to logical languages, logical modeling, formal reasoning and computational logic for computer science and software engineering students......A Gentle introduction to logical languages, logical modeling, formal reasoning and computational logic for computer science and software engineering students...

  15. All-optical noninvasive delayed feedback control of semiconductor lasers

    CERN Document Server

    Schikora, Sylvia

    2013-01-01

    The stabilization of unstable states hidden in the dynamics of a system, in particular the control of chaos, has received much attention in the last years. Sylvia Schikora for the first time applies a well-known control method called delayed feedback control entirely in the all-optical domain. A multisection semiconductor laser receives optical feedback from an external Fabry-Perot interferometer. The control signal is a phase-tunable superposition of the laser signal and provokes the laser to operate in an otherwise unstable periodic state with a period equal to the time delay. The control is noninvasive, because the reflected signal tends to zero when the target state is reached.   The work has been awarded the Carl-Ramsauer-Prize 2012.   Contents ·         All-Optical Control Setup ·         Stable States with Resonant Fabry-Perot Feedback ·         Control of an Unstable Stationary State and of Unstable Selfpulsations ·         Controlling Chaos ·         Con...

  16. All-optical switching via four-wave mixing Bragg scattering in a silicon platform

    CERN Document Server

    Zhao, Yun; Mathews, Jay; Agha, Imad

    2016-01-01

    We employ the process of non-degenerate four-wave mixing Bragg scattering (FWM-BS) to demonstrate all-optical control in a silicon platform. In our configuration, a strong, non-information-carrying pump is mixed with a weak control pump and an input signal in a silicon-on-insulator waveguide. Through the optical nonlinearity of this highly-confining waveguide, the weak pump controls the wavelength conversion process from the signal to an idler, leading to a controlled depletion of the signal. The strong pump, on the other hand, plays the role of a constant bias. In this work, we show experimentally that it is possible to implement this low-power switching technique as a first step towards universal optical logic gates, and test the performance with random binary data. Even at very low powers, where the signal and control pump levels are almost equal, the eye-diagrams remain open, indicating a successful operation of the logic gates.

  17. Demonstration of all-optical two bit digital comparator using self-locked Fabry-Perot laser diode

    Science.gov (United States)

    Nakarmi, Bikash; Rakib-Uddin, M.; Won, Yong Hyub

    2012-02-01

    All-optical two bit digital comparator using single mode Fabry-Perot laser diodes (SMFP-LDs) is proposed and demonstrated with 10 Gbps PRBS signal of 231-1. Digital comparators are one of the important components for decision making circuits, threshold detection, which are used in optical signal processing and optical computing. The basic principle of the comparator is based on injection locking, multi-input injection locking and combinational input injection locking (CMIL) to realize the greater than, less than, and equal to function of the basic comparator circuit. These principles are used to realize the different optical logic gates which are combined together to demonstrate optical comparator with the minimum number of components, making the configuration cheaper and simpler. The proposed method draws less current and hence power effective too. Output waveform diagram and output eye diagram for all three cases of comparator are presented to verify all functions of all-optical comparator.

  18. Tunable All-Optical Filtering and Buffering in a Coupled Quantum Dot-Planar Photonic Crystal Structure

    Institute of Scientific and Technical Information of China (English)

    QIAN Yong; QIAN Jun; WANG Yu-Zhu

    2009-01-01

    We theoretically investigate controlled tunable all-optical filtering and buffering of optical pulses in a hybrid nano-photonic structure,where a single quantum dot (QD) embedded in a photonic crystal nanocavity is sidecoupled between a bare nanocavity and a photonic crystal waveguide.We demonstrate that there is a sharp low-loss transmission peak in the transmission spectrum under even low QD-nanocavity coupling strength and the input optical pulses can be delayed up to several hundred piceseconds within the dephasing time of the QD.The filtering regime can be shifted readily by manipulating the detuning between the QD excitonic transition frequency and resonant frequency of the nanocavity mode,which can be explored in future for on-clup all-optical logic and signal processing.

  19. All-optical ion generation for ion trap loading

    CERN Document Server

    Sheridan, Kevin; Keller, Matthias; 10.1007/s00340-011-4563-7

    2011-01-01

    We have investigated the all-optical generation of ions by photo-ionisation of atoms generated by pulsed laser ablation. A direct comparison between a resistively heated oven source and pulsed laser ablation is reported. Pulsed laser ablation with 10 ns Nd:YAG laser pulses is shown to produce large calcium flux, corresponding to atomic beams produced with oven temperatures greater than 650 K. For an equivalent atomic flux, pulsed laser ablation is shown to produce a thermal load more than one order of magnitude smaller than the oven source. The atomic beam distributions obey Maxwell-Boltzmann statistics with most probable speeds corresponding to temperatures greater than 2200 K. Below a threshold pulse fluence between 280 mJ/cm^2 and 330 mJ/cm^2, the atomic beam is composed exclusively of ground state atoms. For higher fluences ions and excited atoms are generated.

  20. All-Optical Surface Micropatterning by Electric Field Intensity Gradient

    Directory of Open Access Journals (Sweden)

    U. Gertners

    2015-01-01

    Full Text Available In this report an all-optical photo-induced formation of surface relief gratings is shown. For the surface patterning of As2S3 and As4S1.5Se4.5 films a direct holographic recording setup with a 532 nm wavelength Nd:YAG CW laser light was used. Our investigations have shown that the light-induced mass transfer process strongly depends on the material itself and on the polarization of the light. It has been shown that an electric field intensity gradient has to be obtained to achieve a direct patterning. The evolution of a surface relief in relation to recording parameters and thickness of the sample has been investigated in detail.

  1. Self-organized plasmonic metasurfaces for all-optical modulation

    Science.gov (United States)

    Della Valle, G.; Polli, D.; Biagioni, P.; Martella, C.; Giordano, M. C.; Finazzi, M.; Longhi, S.; Duò, L.; Cerullo, G.; Buatier de Mongeot, F.

    2015-06-01

    We experimentally demonstrate a self-organized metasurface with a polarization dependent transmittance that can be dynamically controlled by optical means. The configuration consists of tightly packed plasmonic nanowires with a large dispersion of width and height produced by the defocused ion-beam sputtering of a thin gold film supported on a silica glass. Our results are quantitatively interpreted according to a theoretical model based on the thermomodulational nonlinearity of gold and a finite-element numerical analysis of the absorption and scattering cross-sections of the nanowires. We found that the polarization sensitivity of the metasurface can be strongly enhanced by pumping with ultrashort laser pulses, leading to potential applications in ultrafast all-optical modulation and switching of light.

  2. All-Optical Implementation of the Ant Colony Optimization Algorithm

    Science.gov (United States)

    Hu, Wenchao; Wu, Kan; Shum, Perry Ping; Zheludev, Nikolay I.; Soci, Cesare

    2016-05-01

    We report all-optical implementation of the optimization algorithm for the famous “ant colony” problem. Ant colonies progressively optimize pathway to food discovered by one of the ants through identifying the discovered route with volatile chemicals (pheromones) secreted on the way back from the food deposit. Mathematically this is an important example of graph optimization problem with dynamically changing parameters. Using an optical network with nonlinear waveguides to represent the graph and a feedback loop, we experimentally show that photons traveling through the network behave like ants that dynamically modify the environment to find the shortest pathway to any chosen point in the graph. This proof-of-principle demonstration illustrates how transient nonlinearity in the optical system can be exploited to tackle complex optimization problems directly, on the hardware level, which may be used for self-routing of optical signals in transparent communication networks and energy flow in photonic systems.

  3. All-Optical Switching in Photonic Crystal Cavities

    DEFF Research Database (Denmark)

    Heuck, Mikkel

    All-Optical switching in photonic crystal waveguide-cavity structures is studied predominantly theoretically and numerically, but also from an experimental point of view. We have calculated the first order perturbations to the resonance frequency and decay rate of cavity modes, using a mathematical...... separated. This device was fabricated and characterized by colleagues within the group, and it was shown to perform very well in terms of cross-talk between the signal and pump. Theoretical investigations as well as practical design proposals have resulted from a study of waveguide-cavity structures...... exhibiting Fano resonances. These devices were predicted to be superior to structures with the more well-known Lorentzian line shape in terms of energy consumption and switching contrast. Finally, the mathematical framework of optimal control theory was employed as a general setting, in which the optical...

  4. EIT-based MZ-MMI all-optical switch

    Science.gov (United States)

    Bahrami, A.; Rostami, A.; Nazari, F.; Abbasian, K.

    2010-11-01

    We propose a new control structure for all-optical switching in multimode inference (MMI)-based Mach-Zehnder interferometer (MZI) devices. This structure is composed of an MZI doped by three-level nanocrystals for the realization of electromagnetically induced transparency (EIT) in the lower arm. We use two different intensities of control field for two states of the proposed switch. Using a control field in both of the two switching states is necessary, where the EIT region is transparent. By changing the intensity of the control field, the refractive index of the doped region changes, which makes the phase difference between the two arms of the MZI. Hence, the switching operation takes place. Simulation results show that the extinction ratio of the device is -32dB in the worst case.

  5. Microscopic model for all optical switching in ferromagnets

    Science.gov (United States)

    Cornelissen, T. D.; Córdoba, R.; Koopmans, B.

    2016-04-01

    The microscopic mechanism behind the all optical switching (AOS) in ferromagnets has triggered intense scientific debate. Here, the microscopic three-temperature model is utilized to describe AOS in a perpendicularly magnetized ferromagnetic Co/Pt system. We demonstrate that AOS in such a ferromagnet can be explained with the Inverse Faraday Effect (IFE). The influence of the strength and lifetime of the IFE induced field pulse on the switching process are investigated. We found that because of strong spin-orbit coupling, the minimal lifetime of the IFE needed to obtain switching is of the order of 0.1 ps, which is shorter than previously assumed. Moreover, spatial images of the domain pattern after AOS in Co/Pt, as well as their dependence on applying an opposite magnetic field, are qualitatively reproduced.

  6. All-optical three-dimensional electron pulse compression

    CERN Document Server

    Wong, Liang Jie; Rohwer, Timm; Gedik, Nuh; Johnson, Steven G

    2014-01-01

    We propose an all-optical, three-dimensional electron pulse compression scheme in which Hermite-Gaussian optical modes are used to fashion a three-dimensional optical trap in the electron pulse's rest frame. We show that the correct choices of optical incidence angles are necessary for optimal compression. We obtain analytical expressions for the net impulse imparted by Hermite-Gaussian free-space modes of arbitrary order. Although we focus on electrons, our theory applies to any charged particle and any particle with non-zero polarizability in the Rayleigh regime. We verify our theory numerically using exact solutions to Maxwell's equations for first-order Hermite-Gaussian beams, demonstrating single-electron pulse compression factors of $>10^{2}$ in both longitudinal and transverse dimensions with experimentally realizable optical pulses. The proposed scheme is useful in ultrafast electron imaging for both single- and multi-electron pulse compression, and as a means of circumventing temporal distortions in ...

  7. All-optical reservoir computer based on saturation of absorption.

    Science.gov (United States)

    Dejonckheere, Antoine; Duport, François; Smerieri, Anteo; Fang, Li; Oudar, Jean-Louis; Haelterman, Marc; Massar, Serge

    2014-05-05

    Reservoir computing is a new bio-inspired computation paradigm. It exploits a dynamical system driven by a time-dependent input to carry out computation. For efficient information processing, only a few parameters of the reservoir needs to be tuned, which makes it a promising framework for hardware implementation. Recently, electronic, opto-electronic and all-optical experimental reservoir computers were reported. In those implementations, the nonlinear response of the reservoir is provided by active devices such as optoelectronic modulators or optical amplifiers. By contrast, we propose here the first reservoir computer based on a fully passive nonlinearity, namely the saturable absorption of a semiconductor mirror. Our experimental setup constitutes an important step towards the development of ultrafast low-consumption analog computers.

  8. External cavity based single mode Fabry-Pérot laser diode and its application towards all-optical digital circuits

    Science.gov (United States)

    Nakarmi, Bikash; Zhang, Xuping; Won, Yong Hyub

    2012-11-01

    We have proposed a novel approach of realizing all-optical logic gates and combinational circuit using external cavity based single mode Fabry-Pérot laser diodes (SMFP-LDs). Different techniques and critical parameters for injection locking the any one of the modes of SMFP-LDs are discussed. Taking consideration of wavelength detuning and input injected power, we have proposed and demonstrated multi-input injection locking, supporting beam injection locking with the conventional injection locking which are used for demonstrating different logic gates (NAND, AND, XNOR, XOR, NOT, NOR) and digital circuits (Half adder and Comparator). Since we have used SMFP-LDs, there is no requirement of additional probe beam and associated components as required by other optical technologies making the realization simple in configuration, cost effective and power efficient. Clear output waveforms, eye diagrams, risingfalling times and BER are presented to verify the proposed method. All-optical logic units and digital circuit are demonstrated at the data rate of 10 Gbps with the waveform of NRZ signal waveform and measured eye diagram and BER of the PRBS of 231-1 signal. The maximum power penalty among all demonstrated units is below 1.4 dB at the BER of 10-9.

  9. A Fuzzy Logic Control Strategy for Doubly Fed Induction Generator for Improved Performance under Faulty Operating Conditions

    Directory of Open Access Journals (Sweden)

    G. Venu Madhav

    2014-12-01

    Full Text Available In this paper, decouple PI control for output active and reactive powers which is the common control technique for power converter of Doubly Fed Induction Generator (DFIG is presented. But there are some disadvantages with this control method like uncertainty about the exact model, behavior of some parameters or unpredictable wind speed and tuning of PI parameters. To overcome the mentioned disadvantages a fuzzy logic control of DFIG wind turbine is presented and is compared with PI controller. To validate the proposed scheme, simulation results are presented, these results showed that the performance of fuzzy control of DFIG is excellent and it improves power quality and stability of wind turbine compared to PI controller. The Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine. The entire work is carried out in MATLab/Simulink. Different faulty operating conditions are considered to prove the effective implementation of the proposed control scheme.

  10. 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

  11. Terahertz-driven, all-optical electron gun

    CERN Document Server

    Huang, W Ronny; Wu, Xiaojun; Cankaya, Huseyin; Calendron, Anne-Laure; Ravi, Koustuban; Zhang, Dongfang; Nanni, Emilio A; Hong, Kyung-Han; Kärtner, Franz X

    2016-01-01

    Ultrashort electron beams with narrow energy spread, high charge, and low jitter are essential for resolving phase transitions in metals, semiconductors, and molecular crystals. These semirelativistic beams, produced by phototriggered electron guns, are also injected into accelerators for x-ray light sources. The achievable resolution of these time-resolved electron diffraction or x-ray experiments has been hindered by surface field and timing jitter limitations in conventional RF guns, which thus far are 96 fs, respectively. A gun driven by optically-generated single-cycle THz pulses provides a practical solution to enable not only GV/m surface fields but also absolute timing stability, since the pulses are generated by the same laser as the phototrigger. Here, we demonstrate an all-optical THz gun yielding peak electron energies approaching 1 keV, accelerated by 300 MV/m THz fields in a novel micron-scale waveguide structure. We also achieve quasimonoenergetic, sub-keV bunches with 32 fC of charge, which ca...

  12. All-optical photoacoustic microscopy using a MEMS scanning mirror

    Science.gov (United States)

    Chen, Sung-Liang; Xie, Zhixing; Ling, Tao; Wei, Xunbin; Guo, L. Jay; Wang, Xueding

    2013-03-01

    It has been studied that a potential marker to obtain prognostic information about bladder cancer is tumor neoangiogenesis, which can be quantified by morphometric characteristics such as microvascular density. Photoacoustic microscopy (PAM) can render sensitive three-dimensional (3D) mapping of microvasculature, providing promise to evaluate the neoangiogenesis that is closely related to the diagnosis of bladder cancer. To ensure good image quality, it is desired to acquire bladder PAM images from its inside via the urethra, like conventional cystoscope. Previously, we demonstrated all-optical PAM systems using polymer microring resonators to detect photoacoustic signals and galvanometer mirrors for laser scanning. In this work, we build a miniature PAM system using a microelectromechanical systems (MEMS) scanning mirror, demonstrating a prototype of an endoscopic PAM head capable of high imaging quality of the bladder. The system has high resolutions of 17.5 μm in lateral direction and 19 μm in the axial direction at a distance of 5.4 mm. Images of printed grids and the 3D structure of microvasculature in animal bladders ex vivo by the system are demonstrated.

  13. Description of all-optical network test bed and applications

    Science.gov (United States)

    Marquis, Douglas; Castagnozzi, Daniel M.; Hemenway, B. R.; Parikh, Salil A.; Stevens, Mark L.; Swanson, Eric A.; Thomas, Robert E.; Ozveren, C.; Kaminow, Ivan P.

    1995-12-01

    We describe an all-optical network testbed deployed in the Boston metropolitan area, and some of the experimental applications running over 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 an optical WDM system organized as a hierarchy consisting of local, metropolitan, and wide area nodes that 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. Novel components used to implement the network include fast-tuning 1.5 micrometers distributed Bragg reflector lasers, passive wavelength routers, and broadband optical frequency converters. An overlay control network implemented at 1.3 micrometers allows reliable out-of-band control and standardized network management of all network nodes. We have created interfaces between the AON and commercially available electronic circuit-switched and packet-switched networks. We will report on network applications that can dynamically allocate optical bandwidth between electronic packet-switches based on the offered load presented by users, without requiring interfaces between users and the AON control system. We will also describe video and telemedicine applications running over the network. We have demonstrated an audio/video codec that is directly interfaced to the optical network, and is capable of transmitting high-rate digitized video signals for broadcast or videoconferencing applications. We have also demonstrated a state-of-the-art radiological workstation that uses the AON to transport 2000 X 2000 X 16 bit images from a remote image server.

  14. Simultaneous all-optical digital comparator and dual-directional half-subtractor for two-input 40 Gbit/s DPSK signals employing SOAs

    Science.gov (United States)

    Zhang, Yin; Lei, Lei; Dong, Jianji; Zhang, Xinliang

    2012-02-01

    A module of simultaneous implementation of all-optical digital comparator and dual-directional half-subtractor is proposed. Proof-of-concept experiment is performed at 40 Gbit/s employing the four-wave mixing and cross gain modulation in three parallel semiconductor optical amplifiers. All output results with over 10 dB extinction ratios, clear and wide open eye diagrams, are obtained without using assistant/holding light beam. All-optical half-adder can also be obtained by adjusting the phase shifter of delay interferometer in the proposed module because of its inherent reconfigurability and flexibility. The module would be a promising digital logic elementary circuit in all-optical networks and computing systems.

  15. Logical Varieties in Normative Reasoning

    CERN Document Server

    Burgin, Mark; Mestdagh, de Vey

    2011-01-01

    Although conventional logical systems based on logical calculi have been successfully used in mathematics and beyond, they have definite limitations that restrict their application in many cases. For instance, the principal condition for any logical calculus is its consistency. At the same time, knowledge about large object domains (in science or in practice) is essentially inconsistent. Logical prevarieties and varieties were introduced to eliminate these limitations in a logically correct way. In this paper, the Logic of Reasonable Inferences is described. This logic has been applied successfully to model legal reasoning with inconsistent knowledge. It is demonstrated that this logic is a logical variety and properties of logical varieties related to legal reasoning are developed.

  16. Logical labyrinths

    CERN Document Server

    Smullyan, Raymond

    2008-01-01

    This book features a unique approach to the teaching of mathematical logic by putting it in the context of the puzzles and paradoxes of common language and rational thought. It serves as a bridge from the author's puzzle books to his technical writing in the fascinating field of mathematical logic. Using the logic of lying and truth-telling, the author introduces the readers to informal reasoning preparing them for the formal study of symbolic logic, from propositional logic to first-order logic, a subject that has many important applications to philosophy, mathematics, and computer science. T

  17. Logical entropy of quantum dynamical systems

    Directory of Open Access Journals (Sweden)

    Ebrahimzadeh Abolfazl

    2016-01-01

    Full Text Available This paper introduces the concepts of logical entropy and conditional logical entropy of hnite partitions on a quantum logic. Some of their ergodic properties are presented. Also logical entropy of a quantum dynamical system is dehned and ergodic properties of dynamical systems on a quantum logic are investigated. Finally, the version of Kolmogorov-Sinai theorem is proved.

  18. Fuzzy Logic Engine

    Science.gov (United States)

    Howard, Ayanna

    2005-01-01

    The Fuzzy Logic Engine is a software package that enables users to embed fuzzy-logic modules into their application programs. Fuzzy logic is useful as a means of formulating human expert knowledge and translating it into software to solve problems. Fuzzy logic provides flexibility for modeling relationships between input and output information and is distinguished by its robustness with respect to noise and variations in system parameters. In addition, linguistic fuzzy sets and conditional statements allow systems to make decisions based on imprecise and incomplete information. The user of the Fuzzy Logic Engine need not be an expert in fuzzy logic: it suffices to have a basic understanding of how linguistic rules can be applied to the user's problem. The Fuzzy Logic Engine is divided into two modules: (1) a graphical-interface software tool for creating linguistic fuzzy sets and conditional statements and (2) a fuzzy-logic software library for embedding fuzzy processing capability into current application programs. The graphical- interface tool was developed using the Tcl/Tk programming language. The fuzzy-logic software library was written in the C programming language.

  19. Mathematical logic

    CERN Document Server

    Kleene, Stephen Cole

    2002-01-01

    Undergraduate students with no prior instruction in mathematical logic will benefit from this multi-part text. Part I offers an elementary but thorough overview of mathematical logic of 1st order. Part II introduces some of the newer ideas and the more profound results of logical research in the 20th century. 1967 edition.

  20. Fuzziness in abacus logic

    Science.gov (United States)

    Malhas, Othman Qasim

    1993-10-01

    The concept of “abacus logic” has recently been developed by the author (Malhas, n.d.). In this paper the relation of abacus logic to the concept of fuzziness is explored. It is shown that if a certain “regularity” condition is met, concepts from fuzzy set theory arise naturally within abacus logics. In particular it is shown that every abacus logic then has a “pre-Zadeh orthocomplementation”. It is also shown that it is then possible to associate a fuzzy set with every proposition of abacus logic and that the collection of all such sets satisfies natural conditions expected in systems of fuzzy logic. Finally, the relevance to quantum mechanics is discussed.

  1. All-optical random number generation using highly nonlinear fibers by numerical simulation

    Science.gov (United States)

    Wang, Juanfen; Liang, Junqiang; Li, Pu; Yang, Lingzhen; Wang, Yuncai

    2014-06-01

    A new scheme of all-optical random number generation based on the nonlinear effects in highly nonlinear fibers (HNLF) is proposed. The scheme is comprised of ultra-wide band chaotic entropy source, all-optical sampler, all-optical comparator and all-optical exclusive-or (XOR), which are mainly realized by four-wave mixing (FWM) and cross-phase modulation (XPM) in highly nonlinear fibers. And we achieve 10 Gbit/s random numbers through numerically simulating all the processes. The entire operations are completed in the all-optical domain, which may overcome the bottleneck problem of electronic devices, and apply directly in high-speed all-optical communication network.

  2. Cost effective all-optical fractional OFDM receiver using an arrayed waveguide grating

    Science.gov (United States)

    Nagashima, T.; Cincotti, G.; Murakawa, T.; Shimizu, S.; Hasegawa, M.; Hattori, K.; Okuno, M.; Mino, S.; Himeno, A.; Wada, N.; Uenohara, H.; Konishi, T.

    2016-12-01

    We experimentally demonstrate the feasibility of implementing a cost effective all-optical fractional orthogonal frequency division multiplexing (AO-FrOFDM) receiver using an arrayed waveguide grating (AWG). The all-optical fractional Fourier transform at the receiver is implemented by modifying the second slab coupler from a conventional all-optical discrete Fourier transform AWG. The open eye diagrams obtained from the experimental results indicate that 12 × 10 Gbit/s DBPSK AO-FrOFDM signals were successfully demultiplexed.

  3. All-optical adder/subtractor based on tera-hertz optical asymmetric demultiplexer

    Institute of Scientific and Technical Information of China (English)

    Dilip Kumar Gayen; Rajat Kumar Pal; Jitendra Nath Roy

    2009-01-01

    An all-optical adder/subtractor (A/S) unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed.Tile all-optical A/S unit with a set of all-optical full-adders and optical exclusive-ORs (XORs),can be used to perform a fast central processor unit using optical hardware components.We try to exploit the advantages of TOAD-based optical switch to design an integrated all-optical circuit which can perform binary addition and subtraction.With computer simulation results confirming the described methods,conclusions are given.

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

    Science.gov (United States)

    He, Li; Chen, Jun-Yang; Wang, Jian-Ping; Li, Mo

    2015-09-01

    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.

  5. All-Optical Broadband Excitation of the Motional State of Trapped Ions

    CERN Document Server

    Sheridan, Kevin; Gardner, Amy; Keller, Matthias

    2012-01-01

    We have developed a novel all-optical broadband scheme for exciting, amplifying and measuring the secular motion of ions in a radio frequency trap. Oscillation induced by yocto-Newton optical excitations have been coherently amplified to precisely control and measure the ion's secular motion. Requiring only laser line-of-sight, we have shown that the ion's oscillation amplitude can be precisely controlled. Our broadband excitation scheme generates coherent motion which is robust against variations in the secular frequency. Therefore, our scheme is ideal to excite the desired level of oscillatory motion under conditions where the secular frequency is evolving in time. Measuring the oscillation amplitude through Doppler velocimetry, we have characterized the experimental parameters and compared them with a molecular dynamics simulation which provides a complete description of the system.

  6. Hypo-Steiner heuristic for multicast routing in all-optical WDM mesh networks

    CERN Document Server

    Zhou, Fen; Cousin, Bernard; 10.1007/s11107-010-0243-5

    2010-01-01

    In sparse light splitting all-optical WDM networks, the more destinations a light-tree can accommodate, the fewer light-trees andwavelengths amulticast session will require. In this article, a Hypo-Steiner light-tree algorithm (HSLT) is proposed to construct a HSLT light-tree to include as many destinations as possible. The upper bound cost of the light-trees built by HSLT is given as N(N -1)/2, where N is the number of nodes in the network. The analytical model proves that, under the same condition, more destinations could be held in a HSLT than a Member-Only (Zhang et al., J. Lightware Technol, 18(12), 1917-1927 2000.) light-tree. Extensive simulations not only validate the proof but also show that the proposed heuristic outperforms the existing multicast routing algorithms by a large margin in terms of link stress, throughput, and efficiency ofwavelength usage.

  7. Probabilistic Logic Programming under Answer Sets Semantics

    Institute of Scientific and Technical Information of China (English)

    王洁; 鞠实儿

    2003-01-01

    Although traditional logic programming languages provide powerful tools for knowledge representation, they cannot deal with uncertainty information (e. g. probabilistic information). In this paper, we propose a probabilistic logic programming language by introduce probability into a general logic programming language. The work combines 4-valued logic with probability. Conditional probability can be easily represented in a probabilistic logic program. The semantics of such a probabilistic logic program i...

  8. Understanding Social Media Logic

    Directory of Open Access Journals (Sweden)

    José van Dijck

    2013-08-01

    Full Text Available Over the past decade, social media platforms have penetrated deeply into the mech­anics of everyday life, affecting people's informal interactions, as well as institutional structures and professional routines. Far from being neutral platforms for everyone, social media have changed the conditions and rules of social interaction. In this article, we examine the intricate dynamic between social media platforms, mass media, users, and social institutions by calling attention to social media logic—the norms, strategies, mechanisms, and economies—underpin­ning its dynamics. This logic will be considered in light of what has been identified as mass me­dia logic, which has helped spread the media's powerful discourse outside its institutional boundaries. Theorizing social media logic, we identify four grounding principles—programmabil­ity, popularity, connectivity, and datafication—and argue that these principles become increas­ingly entangled with mass media logic. The logic of social media, rooted in these grounding principles and strategies, is gradually invading all areas of public life. Besides print news and broadcasting, it also affects law and order, social activism, politics, and so forth. Therefore, its sustaining logic and widespread dissemination deserve to be scrutinized in detail in order to better understand its impact in various domains. Concentrating on the tactics and strategies at work in social media logic, we reassess the constellation of power relationships in which social practices unfold, raising questions such as: How does social media logic modify or enhance ex­isting mass media logic? And how is this new media logic exported beyond the boundaries of (social or mass media proper? The underlying principles, tactics, and strategies may be relat­ively simple to identify, but it is much harder to map the complex connections between plat­forms that distribute this logic: users that employ them, technologies that

  9. Microelectromechanical reprogrammable logic device

    KAUST Repository

    Hafiz, M. A. A.

    2016-03-29

    In modern computing, the Boolean logic operations are set by interconnect schemes between the transistors. As the miniaturization in the component level to enhance the computational power is rapidly approaching physical limits, alternative computing methods are vigorously pursued. One of the desired aspects in the future computing approaches is the provision for hardware reconfigurability at run time to allow enhanced functionality. Here we demonstrate a reprogrammable logic device based on the electrothermal frequency modulation scheme of a single microelectromechanical resonator, capable of performing all the fundamental 2-bit logic functions as well as n-bit logic operations. Logic functions are performed by actively tuning the linear resonance frequency of the resonator operated at room temperature and under modest vacuum conditions, reprogrammable by the a.c.-driving frequency. The device is fabricated using complementary metal oxide semiconductor compatible mass fabrication process, suitable for on-chip integration, and promises an alternative electromechanical computing scheme.

  10. All-optical signal processing at 10 GHz using a photonic crystal molecule

    Energy Technology Data Exchange (ETDEWEB)

    Combrié, Sylvain; Lehoucq, Gaëlle; Junay, Alexandra; De Rossi, Alfredo, E-mail: alfredo.derossi@thalesgroup.com [Thales Research and Technology, 1 Avenue A. Fresnel, 91767 Palaiseau (France); Malaguti, Stefania; Bellanca, Gaetano; Trillo, Stefano [Department of Engineering, Università di Ferrara, v. Saragat 1, 44122 Ferrara (Italy); Ménager, Loic [Thales Systèmes Aeroportés, 2 Av. Gay Lussac, 78851 Elancourt (France); Peter Reithmaier, Johann [Institute of Nanostructure Technologies and Analytics, CINSaT, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel (Germany)

    2013-11-04

    We report on 10 GHz operation of an all-optical gate based on an Indium Phosphide Photonic Crystal Molecule. Wavelength conversion and all-optical mixing of microwave signals are demonstrated using the 2 mW output of a mode locked diode laser. The spectral separation of the optical pump and signal is crucial in suppressing optical cross-talk.

  11. Simultaneous all-optical half-adder, half-subtracter, comparator, and decoder based on nonlinear effects harnessing in highly nonlinear fibers

    Science.gov (United States)

    Singh, Karamdeep; Kaur, Gurmeet; Singh, Maninder Lal

    2016-07-01

    A multifunctional combinational logic module capable of performing several signal manipulation tasks all-optically, such as half-addition/subtraction, single-bit comparison, and 2-to-4 decoding simultaneously is proposed. Several logic functions (A+B¯, A.B, A¯.B, A.B¯, A⊕B, and A⊙B) between two input signals A and B are implemented by harnessing a number of nonlinear effects, such as cross-phase modulation (XPM), cross-gain modulation (XGM), and four-wave mixing (FWM) inside only two highly nonlinear fibers (HNLF) arranged in a parallel structure. The NOR gate (A+B¯) is realized by the means of XPM effect in the first HNLF, whereas, A‾.B, A.B¯, and A.B logics have relied on utilization of XGM and FWM processes, respectively, in parametric medium made up of the second HNLF of parallel arrangement. The remaining A⊕B and A⊙B logics required for successful implementation of the proposed simultaneous scheme are attained by temporally combining previously achieved (A‾.B and A.B‾) and (A.B and A+B‾) logics. Quality-factor ≥7.4 and extinction ratio ≥12.30 dB have been achieved at repetition rates of 100 Gbps for all logic functions (A+B‾, A.B, A¯.B, A.B¯, A⊕B, and A⊙B), suggesting successful simultaneous implementation.

  12. Nanomagnetic Logic

    Science.gov (United States)

    Carlton, David Bryan

    influenced by thermal fluctuations. The magnetic ground state containing the answer to the computation is reached by a stochastic process very similar to the thermal annealing of crystalline materials. We will discuss how these dynamics affect the expected reliability, speed, and energy dissipation of NML systems operating under these conditions. Next I will show how a slight change in the properties of the nanomagnets that make up a NML circuit can completely alter the dynamics by which computations take place. The addition of biaxial anisotropy to the magnetic energy landscape creates a metastable state along the hard axis of the nanomagnet. This metastability can be used to remove the stochastic nature of the computation and has large implications for reliability, speed, and energy dissipation which will all be discussed. The changes to NML operation by the addition of biaxial anisotropy introduce new challenges to realizing a commercially viable logic architecture. In the final chapter, I will discuss these challenges and talk about the architectural changes that are necessary to make a working NML circuit based on nanomagnets with biaxial anisotropy.

  13. Logic Meeting

    CERN Document Server

    Tugué, Tosiyuki; Slaman, Theodore

    1989-01-01

    These proceedings include the papers presented at the logic meeting held at the Research Institute for Mathematical Sciences, Kyoto University, in the summer of 1987. The meeting mainly covered the current research in various areas of mathematical logic and its applications in Japan. Several lectures were also presented by logicians from other countries, who visited Japan in the summer of 1987.

  14. EW WEIGHT DEPENDENT ROUTING AND WAVELENGTH ASSIGNMENT STRATEGY FOR ALL OPTICAL NETWORKS IN ABSENCE OF WAVELENGTH CONVERTERS

    Directory of Open Access Journals (Sweden)

    Shilpa S. Patil

    2015-09-01

    Full Text Available In wavelength division multiplexed all optical networks; lightpath establishes a connection between sending and receiving nodes bypassing the electronic processing at intermediate nodes. One of the prime objectives of Routing and Wavelength Assignment (RWA problem is to maximize the number of connections efficiently by choosing the best routes. Although there are several algorithms available, improving the blocking performance in optical networks and finding optimal solutions for RWA problem has still remained a challenging issue. Wavelength conversion can be helpful in restricting the problem of wavelength continuity constraint but it increases complexity in the network. In this paper, we propose new weight dependent routing and wavelength assignment strategy for all optical networks without use of wavelength converters. Proposed weight function reduces blocking probability significantly, improving the network performance at various load conditions. Further, due to absence of wavelength converters, the cost and complexity of network reduces. Results show that the proposed strategy performs better than earlier reported methods.

  15. Ultrafast, low-power, all-optical switching via birefringent phase-matched transverse mode conversion in integrated waveguides

    CERN Document Server

    Hellwig, Tim; Schnack, Martin; Boller, Klaus -J; Fallnich, Carsten

    2015-01-01

    We demonstrate the potential of birefringence-based, all-optical, ultrafast conversion between the transverse modes in integrated optical waveguides by modelling the conversion process by numerically solving the multi-mode coupled nonlinear Schroedinger equations. The observed conversion is induced by a control beam and due to the Kerr effect, resulting in a transient index grating which coherently scatters probe light from one transverse waveguide mode into another. We introduce birefringent phase matching to enable efficient all-optically induced mode conversion at different wavelengths of the control and probe beam. It is shown that tailoring the waveguide geometry can be exploited to explicitly minimize intermodal group delay as well as to maximize the nonlinear coefficient, under the constraint of a phase matching condition. The waveguide geometries investigated here, allow for mode conversion with over two orders of magnitude reduced control pulse energy compared to previous schemes and thereby promise ...

  16. PAPR Reduction in All-optical OFDM Systems Based on Phase Pre-emphasis

    Energy Technology Data Exchange (ETDEWEB)

    He Zhou; Li, Wei; Shao Jing; Liang Xiaojun; Huang Dexiu [Wuhan National Lab for Optoelectronics, Department of Optoelectronics Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Tao Zhiyong [State Key Laboratory of Optical Communication Technologies and Networks, Wuhan Research Institute of Posts and Telecommunications, Wuhan 430074 (China); Deng Zhuanhua, E-mail: hezhou@wri.com.cn, E-mail: weilee@mail.hust.edu.cn [School of Computer Science and Technology, Hubei University of Economics, Wuhan 430205 (China)

    2011-02-01

    This paper investigates the peak-to-average power ratio (PAPR) theory in all-optical orthogonal frequency division multiplexing (OFDM) optical fibre communication systems. We find out that phase pre-emphasis could effectively reduce PAPR in all-optical OFDM communication systems which employ intensity modulation-direct detection (IM-DD) method. An equation is developed and proposed to calculate suitable phasing values for pre-emphasis. Furthermore, we find out that phase pre-emphasis cannot reduce PAPR effectively in all-optical OFDM systems that employ Phase Shift Keying (PSK) or Quadracture Amplitude Modulation (QAM) method.

  17. 40-Gb/s all-optical processing systems using hybrid photonic integration technology

    DEFF Research Database (Denmark)

    Kehayas, E.; Tsiokos, D.I.; Bakopoulos, P.;

    2006-01-01

    This paper presents an experimental performance characterization of all-optical subsystems at 40 Gb/s using interconnected hybrid integrated all-optical semiconductor optical amplifier (SOA) Mach-Zehnder interferometer (MZI) gates and flip-flop prototypes. It was shown that optical gates can...... the potential that all-optical technology can find application in future data-centric networks with efficient and dynamic bandwidth utilization. This paper also reports on the latest photonic integration breakthroughs as a potential migration path for reducing fabrication cost by developing photonic systems...

  18. Engineered materials for all-optical helicity-dependent magnetic switching

    Science.gov (United States)

    Fullerton, Eric

    2014-03-01

    The possibilities of manipulating magnetization without applied magnetic fields have attracted growing attention over the last fifteen years. The low-power manipulation of magnetization, preferably at ultra-short time scales, has become a fundamental challenge with implications for future magnetic information memory and storage technologies. Here we explore the optical manipulation of the magnetization of engineered materials and devices using 100 fs optical pulses. We demonstrate that all optical - helicity dependent switching (AO-HDS) can be observed not only in selected rare-earth transition-metal (RE-TM) alloy films but also in a much broader variety of materials, including alloys, multilayers, heterostructures and RE-free Co-Ir-based synthetic ferrimagnets. The discovery of AO-HDS in RE-free TM-based synthetic ferrimagnets can enable breakthroughs for numerous applications since it exploits materials that are currently used in magnetic data storage, memories and logic technologies. In addition, this materials study of AO-HDS offers valuable insight into the underlying mechanisms involved. Indeed the common denominator of the diverse structures showing AO-HDS in this study is that two ferromagnetic sub-lattices exhibit magnetization compensation (and therefore angular momentum compensation) at temperatures near or above room temperature. We are highlighting that compensation plays a major role and that this compensation can be established at the atomic level as in alloys but also over a larger nanometers scale as in the multilayers or in heterostructures. We will also discuss the potential to extend AO-HDS to new classes of magnetic materials. This work was done in collaboration with S. Mangin, M. Gottwald, C-H. Lambert, D. Steil, V. Uhlíř, L. Pang, M. Hehn, S. Alebrand, M. Cinchetti, G. Malinowski, Y. Fainman, and M. Aeschlimann. Supported by the ANR-10-BLANC-1005 ``Friends,'' a grant from the Advanced Storage Technology Consortium, Partner University Fund

  19. Distributed Logics

    Science.gov (United States)

    2014-10-03

    that must be woven into proofs of security statements. 03-10-2014 Memorandum Report Logic System-on-a-Chip Distributed systems 9888 ASDR&EAssistant...can be removed without damaging the logic. For all propositional letters p, E1. p ⊃ [r] p From now on, a distributed logic contains at least the...a ∈ x iff 〈h〉 ∈ x. These same definitions work for the canonical relation R for r : h y k where now a ∈ MA(k), [r] a, 〈r〉 a ∈ MA(h), x ∈ CF(h), and

  20. Maximum power point tracking algorithm based on sliding mode and fuzzy logic for photovoltaic sources under variable environmental conditions

    Science.gov (United States)

    Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Della, M.; Aillerie, M.

    2017-02-01

    Solar panels have a nonlinear voltage-current characteristic, with a distinct maximum power point (MPP), which depends on the environmental factors, such as temperature and irradiation. In order to continuously harvest maximum power from the solar panels, they have to operate at their MPP despite the inevitable changes in the environment. Various methods for maximum power point tracking (MPPT) were developed and finally implemented in solar power electronic controllers to increase the efficiency in the electricity production originate from renewables. In this paper we compare using Matlab tools Simulink, two different MPP tracking methods, which are, fuzzy logic control (FL) and sliding mode control (SMC), considering their efficiency in solar energy production.

  1. 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....

  2. All-optical diode effect of a nonlinear photonic crystal with a defect

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-jiang; ZHOU Jin-yun; XIAO Wan-neng

    2006-01-01

    An all-optical diode behavior that uses a nonlinear one-dimensional photonic crystal (NPC) with a defect Kerr medium is numerically simulated by the use of a nonlinear finite-difference time-domain (NFDTD) method.The numerical results show that for an incident pulse with appropriate intensity and temporal width,the transmittance can be several times greater in one direction of NPC than in the opposite direction at the pulse carrier frequency. This behaves like an all-optical diode and has promising applications in some areas such as optical isolation and all-optical processing.The ways to obtain low threshold of pulse field strength to realize an all-optical diode are also analyzed in detail.

  3. High bandwidth all-optical 3×3 switch based on multimode interference structures

    Science.gov (United States)

    Le, Duy-Tien; Truong, Cao-Dung; Le, Trung-Thanh

    2017-03-01

    A high bandwidth all-optical 3×3 switch based on general interference multimode interference (GI-MMI) structure is proposed in this study. Two 3×3 multimode interference couplers are cascaded to realize an all-optical switch operating at both wavelengths of 1550 nm and 1310 nm. Two nonlinear directional couplers at two outer-arms of the structure are used as all-optical phase shifters to achieve all switching states and to control the switching states. Analytical expressions for switching operation using the transfer matrix method are presented. The beam propagation method (BPM) is used to design and optimize the whole structure. The optimal design of the all-optical phase shifters and 3×3 MMI couplers are carried out to reduce the switching power and loss.

  4. All-Optical WDM Buffer System Realized by NOLM and Feedback Loop Structure

    Institute of Scientific and Technical Information of China (English)

    Seungwoo Yi; Kyeong-Mo Yoon; Yong-Gi Lee; Jinseob Eom

    2003-01-01

    We propose an all-optical WDM buffer for optical packet switching system, which consists of NOLM and feedback loop. The proposed structure provides more than 40 turn buffering and nice output of buffered data when selected by control signal.

  5. A reconfigurable all-optical VPN based on XGM effect of SOA in WDM PON

    Science.gov (United States)

    Hu, Xiaofeng; Zhang, Liang; Cao, Pan; Wang, Tao; Su, Yikai

    2010-12-01

    We propose and experimentally demonstrate a reconfigurable all-optical VPN scheme enabling intercommunications among different ONUs in a WDM PON. Reconfiguration is realized by dynamically setting wavelength conversion of optical VPN signal using a SOA in the OLT.

  6. All-optical sampling based on quantum-dot semiconductor optical amplifier

    Science.gov (United States)

    Wu, Chen; Wang, Yongjun; Wang, Lina

    2016-11-01

    In recent years, the all-optical signal processing system has become a hot research field of optical communication. This paper focused on the basic research of quantum-dot (QD) semiconductor optical amplifier (SOA) and studied its practical application to all-optical sampling. A multi-level dynamic physical model of QD-SOA is established, and its ultrafast dynamic characteristics are studied through theoretical and simulation research. For further study, an all-optical sampling scheme based on the nonlinear polarization rotation (NPR) effect of QD-SOA is also proposed. This paper analyzed the characteristics of optical switch window and investigated the influence of different control light pulses on switch performance. The presented optical sampling method has an important role in promoting the improvement of all-optical signal processing technology.

  7. Optimization of all-optical EDFA-based Sagnac-interferometer switch.

    Science.gov (United States)

    Wang, Fei; Li, Chunfei

    2007-10-17

    We perform optimization of all-optical EDFA-based Sagnac - interferometer switch through an analytical model and numerical simulations by solving nonlinear Schrödinger equations. The effects of the performance of EDFA on the bit rate and the switching power are investigated for all-optical switch based on self-phase or cross-phase modulation. The simulated results show that ultra-low switching power (EDFA.

  8. All-Optical Terahertz Optical Asymmetric Demultiplexer (toad) Based Binary Comparator:. a Proposal

    Science.gov (United States)

    Chattopadhyay, Tanay

    Comparator determines whether a number is greater than, equals to or less than another number. It plays a significant role in fast central processing unit in all-optical scheme. In all-optical scheme here 1-bit binary comparator is proposed and described by Terahertz Optical Asymmetric Demultiplexer (TOAD) based interferometric switch. Simulation result by Mathcad-7 is also given. Cascading technique of building up the n-bit binary comparator with this 1-bit comparator block is also proposed here.

  9. Transmission performance of all-optically labelled packets using ASK/DPSK orthogonal modulation

    DEFF Research Database (Denmark)

    Chi, Nan; Carlsson, B.; Zhang, Jianfeng

    2002-01-01

    First transmission experiment with all-optically labelled packets consisting of ASK modulated payload and orthogonally modulated DPSK label is demonstrated. The limitation of the laser linewidth and the input extinction ratio are discussed.......First transmission experiment with all-optically labelled packets consisting of ASK modulated payload and orthogonally modulated DPSK label is demonstrated. The limitation of the laser linewidth and the input extinction ratio are discussed....

  10. Magnetic induction tomography using an all-optical ⁸⁷Rb atomic magnetometer.

    Science.gov (United States)

    Wickenbrock, Arne; Jurgilas, Sarunas; Dow, Albert; Marmugi, Luca; Renzoni, Ferruccio

    2014-11-15

    We demonstrate magnetic induction tomography (MIT) with an all-optical atomic magnetometer. Our instrument creates a conductivity map of conductive objects. Both the shape and size of the imaged samples compare very well with the actual shape and size. Given the potential of all-optical atomic magnetometers for miniaturization and extreme sensitivity, the proof-of-principle presented in this Letter opens up promising avenues in the development of instrumentation for MIT.

  11. 160 Gb/s OFDM transmission utilizing an all-optical symbol generator based on PLC

    Science.gov (United States)

    Liang, Xiaojun; Qiao, Yaojun; Li, Wei; Mei, Junyao; Qin, Yi

    2009-11-01

    We demonstrate a 160 Gb/s orthogonal frequency division multiplexing (OFDM) system using an all-optical symbol generator based on planar light circuit (PLC) technology. Excellent bit error rate (BER) is observed after long-distance transmission. The proposed symbol generator fundamentally eliminates the processing speed limits introduced by electronics and is suitable for high integration, making it physically realizable to build high-speed all-optical OFDM systems with a large number of subcarriers.

  12. All-optical clock recovery of NRZ-DPSK signals using optical resonator-type filters

    DEFF Research Database (Denmark)

    Peucheret, Christophe; Seoane, Jorge; Ji, Hua

    2009-01-01

    It is shown how introducing a limited rise time to the driving signal enables all-optical clock recovery of NRZ-DPSK signals generated using a phase modulator. A Fabry-Perot filter is used to generate the optical clock.......It is shown how introducing a limited rise time to the driving signal enables all-optical clock recovery of NRZ-DPSK signals generated using a phase modulator. A Fabry-Perot filter is used to generate the optical clock....

  13. Denial Logic

    CERN Document Server

    Lengyel, Florian

    2012-01-01

    We define Denial Logic DL, a system of justification logic that models an agent whose justified beliefs are false, who cannot avow his own propositional attitudes and who can believe contradictions but not tautologies of classical propositional logic. Using Artemov's natural semantics for justification logic JL, in which justifications are interpreted as sets of formulas, we provide an inductive construction of models of DL, and prove soundness and completeness results for DL. Some logical notions developed for JL, such as constant specifications and the internalization property, are inconsistent with DL. This leads us to define negative constant specifications for DL, which can be used to model agents with justified false beliefs. Denial logic can therefore be relevant to philosophical skepticism. We use DL with what we call coherent negative constant specifications to model a Putnamian brain in a vat with the justified false belief that it is not a brain in a vat, and derive a model of JL in which "I am a b...

  14. All-optical prefix tree adder with the help of terahertz optical asymmetric demultiplexer

    Institute of Scientific and Technical Information of China (English)

    Dilip Kumar Gayen; Tanay Chattopadhyay; Rajat Kumar Pal; Jitendra Nath Roy

    2011-01-01

    We propose and describe an all-optical prefix tree adder with the help of a terahertz optical asymmetric demultiplexer (TOAD) using a set of optical switches. The prefix tree adder is useful in compound adder implementation. It is preferred over the ripple carry adder and the carry lookahead adder. We also describe the principle and possibilities of the all-optical prefix tree adder. The theoretical model is presented and verified through numerical simulation. The new method promises higher processing speed and accuracy. The model can be extended for studying more complex all-optical circuits of enhanced functionality in which the prefix tree adder is the basic building block.%@@ We propose and describe an all-optical prefix tree adder with the help of a terahertz optical asymmetric demultiplexer (TOAD) using a set of optical switches.The prefix tree adder is useful in compound adder implementation.It is preferred over the ripple carry adder and the carry lookahead adder.We also describe the principle and possibilities of the all-optical prefix tree adder.The theoretical model is presented and verified through numerical simulation.The new method promises higher processing speed and accuracy.The model can be extended for studying more complex all-optical circuits of enhanced functionality in which the prefix tree adder is the basic building block.

  15. Design of all-optical multi-level regenerators based on Mach-Zehnder interferometer

    Science.gov (United States)

    Kong, Xiangjian; Wu, Baojian; Zhou, Xingyu; Wan, Qingyao; Jiang, Shanglong; Wen, Feng; Qiu, Kun

    2016-12-01

    We propose a design method for all-optical multi-level regenerators by mimicking the normalized power transfer function (PTF) in the first-order approximation to the ideal step-like PTF, in which a key step is to appropriately select the amplitude and phase conditions of Mach-Zehnder-interferometer (MZI)-based regenerators. As an example, we describe the design process of the self-phase-modulation (SPM)-based MZI regenerator constructed by a section of nonlinear fiber and an optical phase shifter (OPS). It is shown that the parameter of reference power level (RPL) can be regarded as the upper limit of input power, which is useful for the measure of the multi-level regeneration performance. The number of regenerative power levels increases with the RPL parameter. For 4-level pulse amplitude modulated (4PAM) optical signals degraded by the Gaussian noises with the standard deviation of 0.02, the SPM-based MZI regenerator has an average noise reduction ratio (NRR) of 6.5 dB, better than that of 1st-order regenerator by about 5 dB.

  16. A detection method for logic functions suitable for dual-logic synthesis

    Institute of Scientific and Technical Information of China (English)

    Yinshui Xia; Fei Sun; Keyi Mao

    2009-01-01

    Logic functions can be implemented in either AND/OR/NOT-based traditional Boolean (TB) logic or AND/XOR-based Reed-Mul-ler (RM) logic. To the majority of logic functions, it will be beneficial to be partially implemented in both TB logic and RM logic, called dual-logic. In this paper, a detection condition favoring dual-logic synthesis is proposed. A corresponding detection algorithm is devel-oped and implemented in C. The algorithm is applied to test a set of MCNC91 benchmarks for verifying the algorithm. The results show that the proposed algorithm is more efficient than published ones.

  17. Intuitionistic hybrid logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area.......Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area....

  18. Logic and logic-based control

    Institute of Scientific and Technical Information of China (English)

    Hongsheng QI; Daizhan CHENG

    2008-01-01

    This paper gives a matrix expression of logic. Under the matrix expression, a general description of the logical operators is proposed. Using the semi-tensor product of matrices, the proofs of logical equivalences, implications, etc., can be simplified a lot. Certain general properties are revealed. Then, based on matrix expression, the logical operators are extended to multi-valued logic, which provides a foundation for fuzzy logical inference. Finally, we propose a new type of logic, called mix-valued logic, and a new design technique, called logic-based fuzzy control. They provide a numerically computable framework for the application of fuzzy logic for the control of fuzzy systems.

  19. Ultra-High-Speed All-Optical Signal Processing%超高速全光信息处理

    Institute of Scientific and Technical Information of China (English)

    闰连山; 陈智宇; 姜恒云

    2011-01-01

    P比特级光交换网络的发展,要求网络在传输、复用和交换方式上具有灵活性、多样性和高效性,因此基于超高速全光信息处理的网络功能存在较大价值.利用不同光子材料非线性效应(SPM\\XPM\\FWM等)已成功实现了组播、码型变换、逻辑门等不同的全光信息处理单元技术,其中高非线性光纤以其易与现有光纤网络相融合和成本相对较低等特点而具有较大潜力.在总结光信息处理的相关研究进展的基础上,文章重点介绍了偏振复用(PDM)系统中的高速全光信息处理技术,包括基于自相位调制效应(SPM)的全光再生和基于交叉相位调制效应(XPM)的波长转换实现.%Flexible, diverse, and efficient methods of data transmission, multiplexing and exchange are necessary for all-optical networks. All-optical signal processing is highly valuable for network functionality. Multicasting, format conversion, and optical logics can be performed by various nonlinear techniques, including self phase modulation (SPM), cross-phase modulation (XPM), and four-wave mixing (FWM) in different kinds of photonic materials. Highly nonlinear optical fiber has great potential because it is easy to integrate with existing fiber networks and is relatively cheap. This paper reviews current research and highlights ali-optical signal processing techniques in polarization division multiplexed (PDIvl) systems. These techniques include SPM-based all-optical signal regeneration and XPM-based wavelength conversion.

  20. 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.

  1. 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.

  2. All-optical flip-flop based on vertical cavity semiconductor optical amplifiers.

    Science.gov (United States)

    Song, Deqiang; Gauss, Veronica; Zhang, Haijiang; Gross, Matthias; Wen, Pengyue; Esener, Sadik

    2007-10-15

    We report the operation of an all-optical set-reset (SR) flip-flop based on vertical cavity semiconductor optical amplifiers (VCSOAs). This flip-flop is cascadable, has low optical switching power (~10 microW), and has the potential to be integrated on a small footprint (~100 microm(2)). The flip-flop is composed of two cross-coupled electrically pumped VCSOA inverters and uses the principles of cross-gain modulation, polarization gain anisotropy, and highly nonlinear gain characteristics to achieve flip-flop functionality. We believe that, when integrated on chip, this type of all-optical flip-flop opens new prospects for implementing all-optical fast memories and timing regeneration circuits.

  3. Frequency-time coherence for all-optical sampling without optical pulse source

    Science.gov (United States)

    Preußler, Stefan; Raoof Mehrpoor, Gilda; Schneider, Thomas

    2016-09-01

    Sampling is the first step to convert an analogue optical signal into a digital electrical signal. The latter can be further processed and analysed by well-known electrical signal processing methods. Optical pulse sources like mode-locked lasers are commonly incorporated for all-optical sampling, but have several drawbacks. A novel approach for a simple all-optical sampling is to utilise the frequency-time coherence of each signal. The method is based on only using two coupled modulators driven with an electrical sine wave. Since no optical source is required, a simple integration in appropriate platforms, such as Silicon Photonics might be possible. The presented method grants all-optical sampling with electrically tunable bandwidth, repetition rate and time shift.

  4. Field trial of 160 Gb/s all-optical packet switching

    Science.gov (United States)

    Liu, Y.; Herrera, J.; Raz, O.; Tangdiongga, E.; Marti, J.; Ramos, F.; Maxwell, G.; Poustie, A.; Mulvad, H. C. H.; Hill, M. T.; de Waardt, H.; Khoe, G. D.; Koonen, A. M. J.; Dorren, H. J. S.

    2007-11-01

    We present the results of a transmission experiment, over 110 km of field installed fiber, for an all-optical 160 Gb/s packet switching system. The system uses in-band optical labels which are processed entirely in the optical domain using a narrow-band all-optical filter. The label decision information is stored by an optical flip-flop, which output controls a high-speed wavelength converter based on ultra-fast cross-phase modulation in a single semiconductor optical amplifier. The packet switched node is located in between two different fiber sections, each having a length of 54.3-km. The field installed fibers are located around the city of Eindhoven in the Netherlands. The results show how the all-optical switch can effectively route the packets based on the optical information and that such packets may be transmitted across the fiber with an acceptable penalty level.

  5. All-optical virtual private network and ONUs communication in optical OFDM-based PON system.

    Science.gov (United States)

    Zhang, Chongfu; Huang, Jian; Chen, Chen; Qiu, Kun

    2011-11-21

    We propose and demonstrate a novel scheme, which enables all-optical virtual private network (VPN) and all-optical optical network units (ONUs) inter-communications in optical orthogonal frequency-division multiplexing-based passive optical network (OFDM-PON) system using the subcarrier bands allocation for the first time (to our knowledge). We consider the intra-VPN and inter-VPN communications which correspond to two different cases: VPN communication among ONUs in one group and in different groups. The proposed scheme can provide the enhanced security and a more flexible configuration for VPN users compared to the VPN in WDM-PON or TDM-PON systems. The all-optical VPN and inter-ONU communications at 10-Gbit/s with 16 quadrature amplitude modulation (16 QAM) for the proposed optical OFDM-PON system are demonstrated. These results verify that the proposed scheme is feasible.

  6. Performance evaluations for dynamic wavelength routed all-optical multifiber networks

    DEFF Research Database (Denmark)

    Fenger, Christian

    2004-01-01

    This paper presents a study on dynamic wavelength routed all-optical networks by simulating traffic on all-optical networks. A performance study is carried out on dynamic all-optical networks for fixed and free routing. It is explained how multiple fibers correspond to limited wavelength conversion......, and it is explained why the presence of wavelength converters increase the complexity of optical cross connects. We find that both free routing and wavelength conversion lowers the blocking probability significantly. The new contribution is that we determine the gain in blocking probability as function of the number...... of fibers per link and the offered load. We find that multiple fibers reduce the effect of wavelength converters significantly....

  7. Frequency-time coherence for all-optical sampling without optical pulse source

    CERN Document Server

    Preussler, Stefan; Schneider, Thomas

    2016-01-01

    Sampling is the first step to convert an analogue optical signal into a digital electrical signal. The latter can be further processed and analysed by well-known electrical signal processing methods. Optical pulse sources like mode-locked lasers are commonly incorporated for all-optical sampling, but have several drawbacks. A novel approach for a simple all-optical sampling is to utilise the frequency-time coherence of each signal. The method is based on only using two coupled modulators driven with an electrical sine wave, allowing simple integration in appropriate platforms, such as Silicon Photonics. The presented method grants all-optical sampling with electrically tunable bandwidth, repetition rate and time shift.

  8. An all-optical time-delay relay based n a bacteriorhodopsin film

    Institute of Scientific and Technical Information of China (English)

    Chen Gui-Ying; Xu Xu-Xu; Zhang Chun-Ping; Qi Shen-Wen; Song Qi-Wang

    2008-01-01

    Using a special property of dynamic complementary-suppression-modulated transmission (DCSMT) in the bacteriorhodopsin (bR) film,we have demonstrated an all-optical time-delay relay.To extend our work,the relationship between the delay time of the all-optical time-delay relay and parameters of a bR film is numerically studied.We show how the delay time changes with the product of concentration and thickness (PCT) of a bR film.Furthermore,the shortest and longest delay times are given for the relay of 'switch off'.The saturable delay time and maximum delaytime of 'switch on' are also given.How the wavelengths (632.8,568,533 and 412 nm) and intensities of the illuminating light influence the delay time is also discussed.The simulation results are useful for optimizing the design of all-optical time-delay relays.

  9. Security Situation Assessment of All-Optical Network Based on Evidential Reasoning Rule

    Directory of Open Access Journals (Sweden)

    Zhong-Nan Zhao

    2016-01-01

    Full Text Available It is important to determine the security situations of the all-optical network (AON, which is more vulnerable to hacker attacks and faults than other networks in some cases. A new approach of the security situation assessment to the all-optical network is developed in this paper. In the new assessment approach, the evidential reasoning (ER rule is used to integrate various evidences of the security factors including the optical faults and the special attacks in the AON. Furthermore, a new quantification method of the security situation is also proposed. A case study of an all-optical network is conducted to demonstrate the effectiveness and the practicability of the new proposed approach.

  10. Wavelength Routing Algorithm of All Optical Network Based on Traffic Engineering

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    General multi-protocol label switching(GMPLS) based on traffic engineering is one of the possible methods to implement all-optical network. This method implements the network with IP technique and guarantees the quality of service with traffic engineering. Based on the establishment of selecting schemes of optical path and methods of traffic calculation, the wavelength routing algorithm of all-optical network based on traffic engineering is presented by combining with prior route of shortest path and traffic engineering, the algorithm procedures are given, and the actual examples are introduced as well as the analysis on simulation calculation. This research results have certain significance for the achievement of optical switching technique of all-optical network.

  11. Process algebra with four-valued logic

    NARCIS (Netherlands)

    Bergstra, J.A.; Ponse, A.

    2000-01-01

    We propose a combination of a fragment of four-valued logic and process algebra. We present an operational semantics in SOS-style, and a completeness result for ACP with conditionals and four-valued logic.

  12. Efficient ultra-fast all-optical wavelength converters with Ti:PPLN waveguides

    DEFF Research Database (Denmark)

    Nouroozi, Rahman; Suche, Hubertus; Hu, Hao

    2014-01-01

    Applications of packaged and pigtailed (tunable) integrated all-optical Ti:PPLN wavelength converters (AOWC) with different modulation formats (RZ-DQPSK, 16-ary QAM) are reported. The devices take advantage of cascaded second order nonlinear interactions allowing tuning with either one or two...... in transparent all-optical networks (TAON). In addition recent progress with respect to bandwidth and efficiency of the cSHG/DFG-based wavelength converters is reported. The efficiency is increased by pump-resonant wavelength conversion and by increased interaction length in a phase controlled double-pass scheme...

  13. Ultrafast all-optical clock recovery based on phase-only linear optical filtering

    DEFF Research Database (Denmark)

    Maram, Reza; Kong, Deming; Galili, Michael;

    2014-01-01

    We report on a novel technique for all-optical clock recovery from RZ OOK data based on phase-only filtering, significantly enhancing the recovered clock quality and energy-efficiency compared to the use of a Fabry-Perot filter.......We report on a novel technique for all-optical clock recovery from RZ OOK data based on phase-only filtering, significantly enhancing the recovered clock quality and energy-efficiency compared to the use of a Fabry-Perot filter....

  14. 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.

  15. Temporal dynamics of all-optical switching in Photonic Crystal Cavity

    DEFF Research Database (Denmark)

    Colman, Pierre; Heuck, Mikkel; Yu, Yi;

    2014-01-01

    The temporal dynamics of all-optical switching has been investigated in a Photonic Crystal Cavity with a 150fs-40aJ/pulse resolution. This allowed observing for the first time effects like pulse reshaping, pulse delay and intra-cavity Four-Wave-Mixing.......The temporal dynamics of all-optical switching has been investigated in a Photonic Crystal Cavity with a 150fs-40aJ/pulse resolution. This allowed observing for the first time effects like pulse reshaping, pulse delay and intra-cavity Four-Wave-Mixing....

  16. An all-optical buffer based on temporal cavity solitons operating at 10 Gb/s

    CERN Document Server

    Jang, Jae K; Schröder, Jochen; Eggleton, Benjamin J; Murdoch, Stuart G; Coen, Stéphane

    2016-01-01

    We demonstrate the operation of an all-optical buffer based on temporal cavity solitons stored in a nonlinear passive fiber ring resonator. Unwanted acoustic interactions between neighboring solitons are suppressed by modulating the phase of the external laser driving the cavity. A new locking scheme is presented that allows the buffer to operate with an arbitrarily large number of cavity solitons in the loop. Experimentally, we are able to demonstrate the storage of 4536 bits of data, written all-optically into the fiber ring at 10 Gb/s, for 1 minute.

  17. All-optical tunable mirror of VCSEL using electromagnetically induced transparency

    Science.gov (United States)

    Rostami, A.; Abbasian, K.; Khodashenas, P. S.; Janabi-Sharifi, F.

    2008-11-01

    A new and efficient proposal for all-optical tunable mirror of VCSEL using electromagnetically induced transparency (EIT) is proposed. For this purpose a slab doped with quantum dots for realization of 3-level atomic system is considered. Density matrix formulation for time evaluation of the proposed structure is used. The reflection and transmission coefficients of the considered slab are calculated and time development of the related amplitude and output power and threshold current density of VCSEL laser studied. We show that some nanometer tuning can be obtained. So, the proposed idea can open a new realization method of all-optical tunable VCSEL lasers.

  18. Proposal for all-optical controllable switch using dipole induced transparency (DIT)

    Science.gov (United States)

    Eftekhari, K.; Abbasian, K.; Rostami, A.

    2010-05-01

    We propose a novel all-optical controllable switch using photonic crystal cavity. For doing this work, the dipole induced transparency phenomenon realized through interaction of light with multilevel nanocrystals is used. Multilevel nanocrystals are doped to photonic crystal rods. Using the proposed structure and applying the control field, the absorbing medium converts to transparent one and switching operation is obtained. Analytical relation for evaluation of the proposed device considering quantum optical effects is presented and studied by investigation of effects of parameters on switching characteristics. We show that high quality all-optical switching operation can be obtained.

  19. 160 Gb/s Silicon All-Optical Data Modulator based on Cross Phase Modulation

    DEFF Research Database (Denmark)

    Hu, Hao; Pu, Minhao; Ji, Hua

    2012-01-01

    We have demonstrated 160 Gb/s all-optical data modulation with an extinction ratio of 18.5 dB based on XPM in a silicon nanowire. Error free performance is achieved for the optically modulated 160 Gb/s signal.......We have demonstrated 160 Gb/s all-optical data modulation with an extinction ratio of 18.5 dB based on XPM in a silicon nanowire. Error free performance is achieved for the optically modulated 160 Gb/s signal....

  20. All-optical WDM Regeneration of DPSK Signals using Optical Fourier Transformation and Phase Sensitive Amplification

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Kjøller, Niels-Kristian;

    2015-01-01

    We propose a novel all-optical WDM regeneration scheme for DPSK signals based on optical Fourier transformation and phase sensitive amplification. Phase regeneration of a WDM signal consisting of 4x10-Gbit/s phase noise degraded DPSK channels is demonstrated for the first time.......We propose a novel all-optical WDM regeneration scheme for DPSK signals based on optical Fourier transformation and phase sensitive amplification. Phase regeneration of a WDM signal consisting of 4x10-Gbit/s phase noise degraded DPSK channels is demonstrated for the first time....

  1. All-optical ultra-high-speed OFDM to Nyquist-WDM conversion

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2015-01-01

    We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER <10−9 performance for all channels.......We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER

  2. Efficient all-optical switch using a Λ atom in a cavity QED system

    DEFF Research Database (Denmark)

    Nielsen, Anne E. B.; Kerckhoff, Joseph

    2011-01-01

    We propose an all-optical switch constructed from a two-mode optical resonator containing a strongly coupled, three-state system. The coupling allows a weak, continuous wave laser drive to incoherently control the transmission of a much stronger, continuous wave signal laser into (and through) th...

  3. All-Optical Frequency Modulated High Pressure MEMS Sensor for Remote and Distributed Sensing

    DEFF Research Database (Denmark)

    Reck, Kasper; Thomsen, Erik Vilain; Hansen, Ole

    2011-01-01

    We present the design, fabrication and characterization of a new all-optical frequency modulated pressure sensor. Using the tangential strain in a circular membrane, a waveguide with an integrated nanoscale Bragg grating is strained longitudinally proportional to the applied pressure causing a sh...

  4. Modeling of semiconductor devices for high-speed all-optical signal processing

    DEFF Research Database (Denmark)

    Bischoff, Svend; Højfeldt, Sune; Mørk, Jesper

    2001-01-01

    The all-optical signal processing performance of devices based on active semiconductor waveguides is investigated. A large signal model is used to analyse the physical mechanisms limiting the high-speed performance of both semiconductor optical amplifiers (SOAs) and electro-absorption modulators ...

  5. All-optical broadcast and multicast technologies based on PPLN waveguide

    DEFF Research Database (Denmark)

    Ye, Lingyun; Wang, Ju; Hu, Hao

    2013-01-01

    All-optical 1×4 broadcast and 1×3 multicast experiments of a 40-Gb/s return-to-zero on-off keying (RZ-OOK) signal based on a periodically poled lithium niobate (PPLN) waveguide are demonstrated in this letter. Clear opened eye diagrams and error-free performance are achieved for the broadcast...

  6. All-Optical Signal Processing for 640 Gbit/s Applications

    DEFF Research Database (Denmark)

    Mulvad, Hans Christian Hansen

    2008-01-01

    This thesis concerns all-optical signal processing technologies for ultra-high serial data rates up to 640 Gbit/s. Firstly, time-division add-drop multiplexing at 640 Gbit/s is demonstrated for the first time using two different fibre-based switching techniques. Secondly, a novel principle...

  7. Femtosecond all-optical switching in AlGaAs waveguides using a time division interferometer

    Science.gov (United States)

    Lagasse, M. J.; Anderson, K. K.; Haus, H. A.; Fujimoto, J. G.

    1989-05-01

    All-optical switching of femtosecond pulses in AlGaAs waveguides is investigated using a novel time division interferometric technique which eliminates thermal imbalances. In addition to an instantaneous refractive index nonlinearity, free-carrier generation via two-photon absorption produces a response of several hundred picoseconds.

  8. Elastic all-optical multi-hop interconnection in data centers with adaptive spectrum allocation

    Science.gov (United States)

    Hong, Yuanyuan; Hong, Xuezhi; Chen, Jiajia; He, Sailing

    2017-01-01

    In this paper, a novel flex-grid all-optical interconnect scheme that supports transparent multi-hop connections in data centers is proposed. An inter-rack all-optical multi-hop connection is realized with an optical loop employed at flex-grid wavelength selective switches (WSSs) in an intermediate rack rather than by relaying through optical-electric-optical (O-E-O) conversions. Compared with the conventional O-E-O based approach, the proposed all-optical scheme is able to off-load the traffic at intermediate racks, leading to a reduction of the power consumption and cost. The transmission performance of the proposed flex-grid multi-hop all-optical interconnect scheme with various modulation formats, including both coherently detected and directly detected approaches, are investigated by Monte-Carlo simulations. To enhance the spectrum efficiency (SE), number-of-hop adaptive bandwidth allocation is introduced. Numerical results show that the SE can be improved by up to 33.3% at 40 Gbps, and by up to 25% at 100 Gbps. The impact of parameters, such as targeted bit error rate (BER) level and insertion loss of components, on the transmission performance of the proposed approach are also explored. The results show that the maximum SE improvement of the adaptive approach over the non-adaptive one is enhanced with the decrease of the targeted BER levels and the component insertion loss.

  9. Characterisation of a MQW electroabsorption modulator as an all-optical demultiplexer

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo; Romstad, Francis Pascal; Tersigni, Andrea

    2001-01-01

    A detailed experimental investigation of the all-optical switching properties of an InGaAsP MQW electroabsorption modulator has been performed. Using high pump pulse energies and high reverse bias settings, switching windows were demonstrated with extinction ratios up to 25 dB and widths down to 10...

  10. Ultra compact and fast All Optical Flip Flop design in photonic crystal platform

    Science.gov (United States)

    Abbasi, Amin; Noshad, Morteza; Ranjbar, Reza; Kheradmand, Reza

    2012-11-01

    In this work we present a heterostructure All Optical Flip-Flop configuration based on all optical switching with Kerr nonlinear photonic crystal. In this square-hexagonal structure, we propose three different schemes for the cavities in order to show the trade-off between switching time and triggering power. Loss in the system is reasonably low because of the perfect band gap matching at bending points where two lattices join. The proposed RS-Flip Flop has exceptional features, which make it one of the well optimized and most practical structures to be used in the all optical integrated circuits. The novel design has a fast switching action (on the order of a few picoseconds), and low input power (on the order of 100 mW). Furthermore, high contrast of the output signals for ON and OFF states, can help the easy detection or its coupling to the other devices. The structure is fascinatingly uncomplicated, which results in ultra small dimensions which make it suitable to be placed in an all optical integrated circuit. Besides, we provide a profound analytical view on the functioning of the system, as analyzed by the finite difference time domain (FDTD) method.

  11. Analytical expression for the bit error rate of cascaded all-optical regenerators

    DEFF Research Database (Denmark)

    Mørk, Jesper; Öhman, Filip; Bischoff, S.

    2003-01-01

    We derive an approximate analytical expression for the bit error rate of cascaded fiber links containing all-optical 2R-regenerators. A general analysis of the interplay between noise due to amplification and the degree of reshaping (nonlinearity) of the regenerator is performed....

  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. Ultrafast coherent dynamics of a photonic crystal all-optical switch

    DEFF Research Database (Denmark)

    Colman, Pierre; Hansen, Per Lunnemann; Yu, Yi

    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...

  14. All-optical wavelength conversion and signal regeneration using an electroabsorption modulator

    DEFF Research Database (Denmark)

    Højfeldt, Sune; Bischoff, Svend; Mørk, Jesper

    2000-01-01

    All-optical wavelength conversion and signal regeneration based on cross-absorption modulation in an InGaAsP quantum well electroabsorption modulator (EAM) is studied at different bit rates. We present theoretical results showing wavelength conversion efficiency in agreement with existing...

  15. All-optical wavelength conversion and signal regeneration using an electroabsorption modulator

    DEFF Research Database (Denmark)

    Højfeldt, Sune; Bischoff, Svend; Mørk, Jesper

    1999-01-01

    All-optical wavelength conversion in an InGaAsP quantum well electroabsorption modulator is studied at different bit-rates. We present theoretical results showing wavelength conversion efficiency in agreement with existing experimental results, and signal regeneration capability is demonstrated....

  16. 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.

  17. A Novel All-optical Wavelength Converter Based on Self-pump Four-wave Mixing

    Institute of Scientific and Technical Information of China (English)

    CHEN Jianxiao; CHEN Zhangyuan; TAO Zhenning; WU Deming; XU Anshi; WANG Ziyu

    2002-01-01

    A novel scheme of all-optical wavelength converter(AOWC) based on dual pump four-wave mixing(DP-FWM) was demonstrated. To suppress the ASE noise of the semiconductor optical amplifier (SOA), one of the two pumps was generated interiorly from a loop laser constructed mainly by tunable optical filter and SOA. The theoretical model and some experimental results were presented.

  18. 8x40 Gb/s RZ all-optical broadcasting utilizing an electroabsorption modulator

    DEFF Research Database (Denmark)

    Xu, Lin; Chi, Nan; Yvind, Kresten

    2004-01-01

    We experimentally demonstrate all-optical broadcasting through simultaneous 8 × 40 Gb/s wavelength conversion in the RZ format based on cross absorption modulation in an electroabsorption modulator. The original intensity-modulated information is successfully duplicated onto eight wavelengths...

  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. Routing and wavelength assignment based on normalized resource and constraints for all-optical network

    Science.gov (United States)

    Joo, Seong-Soon; Nam, Hyun-Soon; Lim, Chang-Kyu

    2003-08-01

    With the rapid growth of the Optical Internet, high capacity pipes is finally destined to support end-to-end IP on the WDM optical network. Newly launched 2D MEMS optical switching module in the market supports that expectations of upcoming a transparent optical cross-connect in the network have encouraged the field applicable research on establishing real all-optical transparent network. To open up a customer-driven bandwidth services, design of the optical transport network becomes more challenging task in terms of optimal network resource usage. This paper presents a practical approach to finding a route and wavelength assignment for wavelength routed all-optical network, which has λ-plane OXC switches and wavelength converters, and supports that optical paths are randomly set up and released by dynamic wavelength provisioning to create bandwidth between end users with timescales on the order of seconds or milliseconds. We suggest three constraints to make the RWA problem become more practical one on deployment for wavelength routed all-optical network in network view: limitation on maximum hop of a route within bearable optical network impairments, limitation on minimum hops to travel before converting a wavelength, and limitation on calculation time to find all routes for connections requested at once. We design the NRCD (Normalized Resource and Constraints for All-Optical Network RWA Design) algorithm for the Tera OXC: network resource for a route is calculated by the number of internal switching paths established in each OXC nodes on the route, and is normalized by ratio of number of paths established and number of paths equipped in a node. We show that it fits for the RWA algorithm of the wavelength routed all-optical network through real experiments on the distributed objects platform.

  1. 四值非全序逻辑系统中公式的条件随机真度%The Conditional Randomized Truth Degree of Formulas in R0-Type 4-valued Non-totally Ordered Propositional Logic

    Institute of Scientific and Technical Information of China (English)

    左卫兵; 原胜利

    2012-01-01

    基于条件概率的思想,利用赋值集的随机化方法,在四值非全序逻辑系统中引入公式的条件随机真度,证明了条件随机真度的MP规则和HS规则.引入公式间的条件随机相似度和条件伪距离,建立了条件随机逻辑度量空间,推导出条件伪距离的若干性质,证明了条件随机逻辑度量空间中逻辑运算的连续性,并初步研究了给定条件下的近似推理理论.%Based on conditional probability, using the randomization method of valuation set, the concept of conditional randomized truth degree of formulas is introduced in the Ro-type 4-valued non-totally ordered propositional logic. The MP rule and HS rule of conditional randomized truth degrees are proved. The concepts of conditional randomized similarity and conditional pseudo-metric between formulas are introduced and conditional randomized logic metric space is built. Several properties of conditional pseudo-metric are deduced and it is proved that the logical operations are continuous on conditional randomized logic metric space. Finally the theory of approximate reasoning under certain information is given.

  2. Parametric logic: Foundations

    Institute of Scientific and Technical Information of China (English)

    林作铨; 李未

    1995-01-01

    Parametric logic is introduced. The language, semantics and axiom system of parametric logic are defined. Completeness theorem of parametric logic is provided. Parametric logic has formal ability powerful enough to capture a wide class of logic as its special cases, and therefore can be viewed as a uniform basis for modern logics.

  3. Ultrafast, low-power, all-optical switching via birefringent phase-matched transverse mode conversion in integrated waveguides.

    Science.gov (United States)

    Hellwig, Tim; Epping, Jörn P; Schnack, Martin; Boller, Klaus-J; Fallnich, Carsten

    2015-07-27

    We demonstrate the potential of birefringence-based, all-optical, ultrafast conversion between the transverse modes in integrated optical waveguides by modelling the conversion process by numerically solving the multi-mode coupled nonlinear Schroedinger equations. The observed conversion is induced by a control beam and due to the Kerr effect, resulting in a transient index grating which coherently scatters probe light from one transverse waveguide mode into another. We introduce birefringent phase matching to enable efficient all-optically induced mode conversion at different wavelengths of the control and probe beam. It is shown that tailoring the waveguide geometry can be exploited to explicitly minimize intermodal group delay as well as to maximize the nonlinear coefficient, under the constraint of a phase matching condition. The waveguide geometries investigated here, allow for mode conversion with over two orders of magnitude reduced control pulse energy compared to previous schemes and thereby promise nonlinear mode switching exceeding efficiencies of 90% at switching energies below 1 nJ.

  4. Logical Behaviorism

    OpenAIRE

    Malcolm, Norman; Altuner, Ilyas

    2015-01-01

    The paper deals exclusively with the doctrine called ‘Logical Behaviorism’. Although this position does not vogue it enjoyed in the 1930s and 1940s, it will always possess a compelling attraction for anyone who is perplexed by the psychological concepts, who has become aware of worthlessness of an appeal to introspection as an account of how we learn those concepts, and he has no inclination to identify mind with brain. There, of course, are other forms of behaviorism, and of reductionism, wh...

  5. All-Optical Detection of Acoustic Pressure Waves with applications in Photo-Acoustic Spectroscopy

    CERN Document Server

    Westergaard, Philip G

    2016-01-01

    An all-optical detection method for the detection of acoustic pressure waves is demonstrated. The detection system is based on a stripped (bare) single-mode fiber. The fiber vibrates as a standard cantilever and the optical output from the fiber is imaged to a displacement-sensitive optical detector. The absence of a conventional microphone makes the demonstrated system less susceptible to the effects that a hazardous environment might have on the sensor. The sensor is also useful for measurements in high temperature (above $200^{\\circ}$C) environments where conventional microphones will not operate. The proof-of-concept of the all-optical detection method is demonstrated by detecting sound waves generated by the photo-acoustic effect of NO$_2$ excited by a 455 nm LED, where a detection sensitivity of approximately 50 ppm was achieved.

  6. All Optical Stabilization of a Soliton Frequency Comb in a Crystalline Microresonator

    CERN Document Server

    Jost, J D; Herr, T; Lecaplain, C; Brasch, V; Pfeiffer, M H P; Kippenberg, T J

    2015-01-01

    Microresonator based optical frequency combs (MFC) have demonstrated promise in extending the capabilities of optical frequency combs. Here we demonstrate all optical stabilization of a low noise temporal soliton based MFC in a crystalline resonator via a new technique to control the repetition rate. This is accomplished by thermally heating the microresonator with an additional probe laser coupled to an auxiliary optical resonator mode. The offset frequency is controlled by stabilization of the pump laser frequency to a reference optical frequency comb. We analyze the stabilization by performing an out of loop comparison and measure the overlapping Allan deviation. This all optical stabilization technique can prove useful as a low added noise actuator for self-referenced microresonator frequency combs.

  7. All-Optical Signal processing using Highly Nonlinear Photonic Crystal Fiber

    DEFF Research Database (Denmark)

    Andersen, Peter Andreas

    2006-01-01

    of modulation format of the signal. The modulation format is also dependent on transmission in the optical system and dependent on the pulse source used to generate the supercontinuum. It is believed that by satisfying strict demands on the pulse sources and the fiber design, could the use of a supercontinuum...... of a transparent all-optical wavelength converter shows one of the many possible applications for a HNL-PCF in optical systems. A combination of a HNL-PCF and FWM generates a very powerful tool for all-optical wavelength conversion. The transparency of an optical system is tested by mixing different modulation...... an OPC using this fiber. Optical phase conjugation is one way of dispersion compensating a fiber span. The experiment performed in chapter 5 shows that, by using optical phase conjugation in a HNL-PCF, a successful transmission over a PCF fiber link is made possible. Without the optical phase conjugation...

  8. All-optical code routing in interconnected optical CDMA and WDM ring networks.

    Science.gov (United States)

    Deng, Yanhua; Fok, Mable P; Prucnal, Paul R; Wang, Ting

    2010-11-01

    We propose an all-optical hybrid network composed of optical code division multiple access (CDMA) rings interconnecting through a reconfigurable wavelength division multiplexing (WDM) metro area ring. This network retains the advantages of both the optical CDMA and WDM techniques, including asynchronous access and differentiated quality of service, while removing the hard limit on the number of subscribers and increasing network flexibility. The all-optical network is enabled by using nonlinear optical loop mirrors in an add/drop router (ADR) that performs code conversion, dropping, and switching asynchronously. We experimentally demonstrate the functionalities of the ADR in the proposed scheme asynchronously and obtain error-free performance. The bit-error rate measurements show acceptable power penalties for different code routes.

  9. Study of all-optical sampling using a semiconductor optical amplifier

    Science.gov (United States)

    Wu, Chen; Wang, Yongjun; Wang, Lina; Wang, Fu

    2016-08-01

    All-optical sampling is an important research content of all-optical signal processing. In recent years, the application of the semiconductor optical amplifier (SOA) in optical sampling has attracted lots of attention because of its small volume and large nonlinear coefficient. We propose an optical sampling model based on nonlinear polarization rotation effect of the SOA. The proposed scheme has the advantages of high sampling speed and small input pump power, and a transfer curve with good linearity was obtained through simulation. To evaluate the performance of sampling, we analyze the linearity and efficiency of sampling pulse considering the impact of pulse width and analog signal frequency. We achieve the sampling of analog signal to high frequency pulse and exchange the positions of probe light and pump light to study another sampling.

  10. Influence Factors of an All-Optical Recovered Clock from Two-Section DFB Lasers

    Institute of Scientific and Technical Information of China (English)

    KONG Duan-Hua; ZHU Hong-Liang; LIANG Song; WANG Bao-Jun; BIAN Jing; MA Li; YU Wen-Ke; LOU Cai-Yun

    2011-01-01

    @@ All-optical clock recovery by a two-section DFB laser with different injection wavelengths is demonstrated exper-imentally at 38.5GHz.An optical clock with a root-mean-square timing jitter of 250fs and an extinction ratio of 12.1 dB is obtained with 1551 run injection.The timing jitter of the recovered clock is further investigated for various intensity ratios of the two DFB emission modes.%All-optical clock recovery by a Iwu-wcliuii DFIS laser v, Uh different ijijcciiuii wavnk'U^lhs is dt-iwm^.ttnind experimentally af 3H.5GBz. An optical clock with a root-mean-square timing jitter of 2.50& and an extinction ratio of !2.idB is obtained with 1551 nm injection. The timing jitter of the recovered duck is Further invesUgui id fo: various intensity ratios of [Jit two DFB emission modes.

  11. All-optical scanhead for ultrasound and photoacoustic imaging-Imaging mode switching by dichroic filtering.

    Science.gov (United States)

    Hsieh, Bao-Yu; Chen, Sung-Liang; Ling, Tao; Guo, L Jay; Li, Pai-Chi

    2014-03-01

    Ultrasound (US) and photoacoustic (PA) multimodality imaging has the advantage of combining good acoustic resolution with high optical contrast. The use of an all-optical scanhead for both imaging modalities can simplify integration of the two systems and miniaturize the imaging scanhead. Herein we propose and demonstrate an all-optical US/PA scanhead using a thin plate for optoacoustic generation in US imaging, a polymer microring resonator for acoustic detection, and a dichroic filter to switch between the two imaging modes by changing the laser wavelength. A synthetic-aperture focusing technique is used to improve the resolution and contrast. Phantom images demonstrate the feasibility of this design, and show that axial and lateral resolutions of 125 μm and 2.52°, respectively, are possible.

  12. All-optical control of microfiber resonator by graphene's photothermal effect

    Science.gov (United States)

    Wang, Yadong; Gan, Xuetao; Zhao, Chenyang; Fang, Liang; Mao, Dong; Xu, Yiping; Zhang, Fanlu; Xi, Teli; Ren, Liyong; Zhao, Jianlin

    2016-04-01

    We demonstrate an efficient all-optical control of microfiber resonator assisted by graphene's photothermal effect. Wrapping graphene onto a microfiber resonator, the light-graphene interaction can be strongly enhanced via the resonantly circulating light, which enables a significant modulation of the resonance with a resonant wavelength shift rate of 71 pm/mW when pumped by a 1540 nm laser. The optically controlled resonator enables the implementation of low threshold optical bistability and switching with an extinction ratio exceeding 13 dB. The thin and compact structure promises a fast response speed of the control, with a rise (fall) time of 294.7 μs (212.2 μs) following the 10%-90% rule. The proposed device, with the advantages of compact structure, all-optical control, and low power acquirement, offers great potential in the miniaturization of active in-fiber photonic devices.

  13. 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.

  14. Ultrafast, broadband, and configurable midinfrared all-optical switching in nonlinear graphene plasmonic waveguides

    Directory of Open Access Journals (Sweden)

    Kelvin J. A. Ooi

    2016-07-01

    Full Text Available Graphene plasmonics provides a unique and excellent platform for nonlinear all-optical switching, owing to its high nonlinear conductivity and tight optical confinement. In this paper, we show that impressive switching performance on graphene plasmonic waveguides could be obtained for both phase and extinction modulations at sub-MW/cm2 optical pump intensities. Additionally, we find that the large surface-induced nonlinearity enhancement that comes from the tight confinement effect can potentially drive the propagating plasmon pump power down to the pW range. The graphene plasmonic waveguides have highly configurable Fermi-levels through electrostatic-gating, allowing for versatility in device design and a broadband optical response. The high capabilities of nonlinear graphene plasmonics would eventually pave the way for the adoption of the graphene plasmonics platform in future all-optical nanocircuitry.

  15. Recovery Management in All Optical Networks Using Biologically-Inspired Complex Adaptive System

    Directory of Open Access Journals (Sweden)

    Inadyuti Dutt

    2013-01-01

    Full Text Available All-Optical Networks have the ability to display varied advantages like performance efficiency, throughput etc but their efficiency depends on their survivability as they are attack prone. These attacks can be categorised as active or passive because they try to access information within the network or alter the information in the network. The attack once detected has to be recovered by formulating back-up or alternative paths. The proposed heuristic uses biologically inspired Complex Adaptive System, inspired by Natural Immune System. The study shows that natural immune system exhibit unique behaviour of detecting foreign bodies in our body and removing them on their first occurrences. This phenomenon is being utilised in the proposed heuristic for recovery management in All-optical Network

  16. All-Optical Temporal Differentiator Using a High Resolution Optical Arbitrary Waveform Shaper

    Institute of Scientific and Technical Information of China (English)

    DONG Jian-Ji; LUO Bo-Wen; ZHANG Yin; LEI Lei; HUANG De-Xiu; ZHANG Xin-Liang

    2012-01-01

    We experimentally demonstrate an all-optical temporal differentiator using a high resolution optical arbitrary waveform shaper, which is based on liquid crystal on silicon switching elements, and both amplitude and phase of the spectrum are programmable. By designing specific transfer functions with the optical waveform shaper, we obtain first-, second-, and third-order differentiators for periodic pulses with small average errors. We also theoretically analyze the bandwidth limitation of optical waveform shaper on the differentiator.%We experimentally demonstrate an all-optical temporal differentiator using a high resolution optical arbitrary waveform shaper,which is based on liquid crystal on silicon switching elements,and both amplitude and phase of the spectrum are programmable.By designing specific transfer functions with the optical waveform shaper,we obtain first-,second-,and third-order differentiators for periodic pulses with small average errors.We also theoretically analyze the bandwidth limitation of optical waveform shaper on the differentiator.

  17. Optical bistability in artificial composite nanoscale molecules: Towards all optical processing at the nanoscale

    CERN Document Server

    Malyshev, A V

    2010-01-01

    Optical response of artificial composite nanoscale molecules comprising a closely spaced noble metal nanoparticle and a semiconductor quantum dot have been studied theoretically. We consider a system composed of an Au particle and CdSe or CdSe/ZnSe quantum dot and predict optical bistability and hysteresis in its response, which suggests various applications, in particular, all-optical processing and optical memory.

  18. Coherent all-optical switching in a bistable waveguide-cavity-waveguide system

    DEFF Research Database (Denmark)

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

    2011-01-01

    All optical switching based on non-linear material effects is a promising technique for use in future optical communication systems. Promising advances in the field has been achieved using optical microcavities in photonic crystals to increase the optical field strength and hence reduce...... the required power of the input field [1]. In this work we consider an alternative method of switching, in which the input power is kept constant and only the phase of the input field is varied....

  19. A phase insensitive all-optical router based on nonlinear lenslike planar waveguides.

    Science.gov (United States)

    Mateo, Eduardo; Liñares, Jesús

    2005-05-02

    We present the design of an all-optical router based on the properties of both propagation and interaction of Gaussian beams in lenslike planar guides. Variational results of single co- and counterpropagation are derived and used to design three integrated optical devices, that is, a header extraction device, an optical bistable device and a data routing device, which perform an ultrafast, phase-insensitive and fiber compatible routing operation in the optical domain.

  20. New all-optical wavelength auto-router based on spatial solitons.

    Science.gov (United States)

    Wu, Yaw-Dong

    2004-09-06

    We propose a novel all-optical wavelength auto-router based on spatial solitons. By using the swing effect of spatial solitons in a Kerr-type nonlinear medium, the proposed nonlinear waveguide structure could function as a self-routing wavelength division multiplexer (WDM). It could be a potential key component in the applications of ultra-high-speed and ultra-high-capacity optical communications and optical data processing systems.

  1. An all-optical buffer based on polarization rotation in an EAM

    Institute of Scientific and Technical Information of China (English)

    Wang Kui-Ru; Kuang Hai; Wang Yong-Jun; Yuan Jin-Hui; Yan Bin-Bin

    2013-01-01

    A theoretical model of the refractive index changes of the TE and TM modes in an electro-absorption modulator (EAM) is deduced.The photon absorption and refractive index changes are analyzed numerically.The influence of pump intensity on the phase difference between the TE and TM modes is studied.The polarization rotation effect is obtained in the EAM,and a novel all-optical fiber loop buffer is designed.

  2. Femtojoule-Scale All-Optical Latching and Modulation via Cavity Nonlinear Optics

    Science.gov (United States)

    Kwon, Yeong-Dae; Armen, Michael A.; Mabuchi, Hideo

    2013-11-01

    We experimentally characterize Hopf bifurcation phenomena at femtojoule energy scales in a multiatom cavity quantum electrodynamical (cavity QED) system and demonstrate how such behaviors can be exploited in the design of all-optical memory and modulation devices. The data are analyzed by using a semiclassical model that explicitly treats heterogeneous coupling of atoms to the cavity mode. Our results highlight the interest of cavity QED systems for ultralow power photonic signal processing as well as for fundamental studies of mesoscopic nonlinear dynamics.

  3. All optical contention detection and resolution for asynchronous variable length optical packets switching

    Science.gov (United States)

    Farhat, Rim; Farhat, Amel; Menif, Mourad

    2016-04-01

    We proposed a novel 2×2 all optical packet switching router architecture supporting asynchronous, labelled and variablelength packet. A proof of concept through Matlab Simulink simulation is validated. Then we discussed the three possible scenarios to demonstrate the contention resolution technique based on deflection routing. We have showing that the contending packet is detected and forwarded according FIFO (First In First Out) strategy to another output.

  4. All optical implementation of a time-domain ptychographic pulse reconstruction set-up

    CERN Document Server

    Spangenberg, Dirk-Mathys; Rohwer, Erich; Feurer, Thomas

    2016-01-01

    An all optical implementation of pulse reconstruction using time-domain ptychography is demonstrated showing excellent results. Setup and reconstruction are easy to implement and a number of drawbacks found in other second order techniques are removed, such as the beam splitter modifying the pulse under consideration, the time ambiguity, or the strict correspondence between time delay increment and temporal resolution. Ptychography generally performs superior to algorithms based on general projections, requires considerable less computational effort and is much less susceptible to noise.

  5. Supporting IP dense mode multicast routing protocols in WDM all-optical networks

    Science.gov (United States)

    Salvador, Marcos R.; Heemstra de Groot, Sonia; Dey, Diptish

    2000-09-01

    Recent developments in all-optical networking and wavelength division multiplexing technologies allow for the support of optical multicasting, a missing feature towards the optical Internet. In this paper we propose a protocol to construct source-rooted WDM multicast trees. The protocol works under dense mode multicasting routing IP protocols and supports network nodes with different degrees of light splitting, wavelength conversion, and add/drop capabilities.

  6. All-optical analog-to-digital conversion using optical interconnection for gray code coding

    Science.gov (United States)

    Nishitani, Takashi; Konishi, Tsuyoshi; Itoh, Kazuyoshi

    2006-09-01

    The gray code based all-optical analog-to-digital conversion (ADC) using optical interconnection is described. Recent tremendous growths of optical communications and digital signal processing have encouraged the demand of high-speed and high-resolution ADC. To pursue a high-speed and high-resolution ADC, optical approaches have attracted much attention recently. ADC generally consists of three procedures: sampling, quantization and coding. Whereas the optical sampling techniques have been proposed and realized, the optical quantization and coding techniques have investigated depending on various applications. For the application to the binary detection of a high-speed digital signal, we previously proposed an all-optical ADC which consists of optical quantization using self-frequency shifting in a fiber and optical coding using optical interconnection for general binary code. In addition, since we can easily prepare optical interconnection patterns corresponding to the various codes, this technique can be used in any coding schemes. In this paper, we demonstrate the gray code based all-optical ADC to verify its scalability. Experimental results show that the 8-levels analog signals can be successfully converted into the bitwise allocated 3-bit gray code.

  7. Logic and truth: Some logics without theorems

    Directory of Open Access Journals (Sweden)

    Jayanta Sen

    2008-08-01

    Full Text Available Two types of logical consequence are compared: one, with respect to matrix and designated elements and the other with respect to ordering in a suitable algebraic structure. Particular emphasis is laid on algebraic structures in which there is no top-element relative to the ordering. The significance of this special condition is discussed. Sequent calculi for a number of such structures are developed. As a consequence it is re-established that the notion of truth as such, not to speak of tautologies, is inessential in order to define validity of an argument.

  8. A Novel All-Optical Switch in a Double-Loop Sagnac Ring Coupled with a Nonlinear Ring Resonator

    Institute of Scientific and Technical Information of China (English)

    LI Jun-Qing; LI Li; ZHAO Jia-Qun; LI Chun-Fei

    2004-01-01

    @@ We propose a novel configuration of all-optical switch based on a double-loop Sagnac ring coupled with a nonlinear ring resonator. In the case of self-phase modulation, the reducing switching threshold power down to mW is predicted, which is the improvement of earlier works on all-optical switches. The switch optimization is analysed.A way to increase the response speed of all-optical switches is suggested.

  9. Tribological Performance Optimization of Electroless Ni-B Coating under Lubricated Condition using Hybrid Grey Fuzzy Logic

    Science.gov (United States)

    Mukhopadhyay, Arkadeb; Duari, Santanu; Barman, Tapan Kumar; Sahoo, Prasanta

    2016-10-01

    Deposition of nickel coating and its alloys using electroless method has received wide acceptance by researchers and even the industries because of their excellent tribological properties. The present experimental investigation deals with the behaviour of electroless Ni-B coating under lubricated condition on a pin-on-disc tribotester. An attempt is made to minimize the friction and wear characteristics simultaneously by optimizing three test parameters i.e. the applied normal load, speed and time of sliding using grey fuzzy reasoning analysis. The friction and wear tests are carried out based on Taguchi's L27 orthogonal array of experiments. 3D surface and contour plots are generated to analyze the trends in variation of friction and wear of the deposits considering the combined effect of the design variables. Analysis of variance is done to find out the contribution of each test parameter and their interactions in controlling the friction and wear behaviour of electroless Ni-B coating. Surface morphology, phase transformation and coating composition analysis are done with the help of scanning electron microscopy, X-ray diffraction analysis and energy dispersive X-ray analysis respectively.

  10. Tribological Performance Optimization of Electroless Ni-B Coating under Lubricated Condition using Hybrid Grey Fuzzy Logic

    Science.gov (United States)

    Mukhopadhyay, Arkadeb; Duari, Santanu; Barman, Tapan Kumar; Sahoo, Prasanta

    2015-11-01

    Deposition of nickel coating and its alloys using electroless method has received wide acceptance by researchers and even the industries because of their excellent tribological properties. The present experimental investigation deals with the behaviour of electroless Ni-B coating under lubricated condition on a pin-on-disc tribotester. An attempt is made to minimize the friction and wear characteristics simultaneously by optimizing three test parameters i.e. the applied normal load, speed and time of sliding using grey fuzzy reasoning analysis. The friction and wear tests are carried out based on Taguchi's L27 orthogonal array of experiments. 3D surface and contour plots are generated to analyze the trends in variation of friction and wear of the deposits considering the combined effect of the design variables. Analysis of variance is done to find out the contribution of each test parameter and their interactions in controlling the friction and wear behaviour of electroless Ni-B coating. Surface morphology, phase transformation and coating composition analysis are done with the help of scanning electron microscopy, X-ray diffraction analysis and energy dispersive X-ray analysis respectively.

  11. All-optical NRZ-to-RZ data format conversion with optically injected laser diode or semiconductor optical amplifier

    Science.gov (United States)

    Lin, Gong-Ru; Chang, Yung-Cheng; Yu, Kun-Chieh

    2006-09-01

    By injecting the optical NRZ data into a Fabry-Perot laser diode (FPLD) synchronously modulated at below threshold condition or a semiconductor optical amplifier (SOA) gain-depleted with a backward injected clock stream, the all-optical non-return to zero (NRZ) to return-to-zero (RZ) format conversion of a STM-64 date-stream for synchronous digital hierarchy (SDH) or an OC-192 data stream for synchronous optical network (SONET) in high-speed fiber-optic communication link can be performed. Without the assistance of any complicated RF electronic circuitry, the output RZ data-stream at bit rate of up to 10 Gbit/s is successfully transformed in the optically NRZ injection-locked FPLD, in which the incoming NRZ data induces gain-switching of the FPLD without DC driving current or at below threshold condition. A power penalty of 1.2 dB is measured after NRZ-to-RZ transformation in the FPLD. Alternatively, the all-optical 10Gbits/s NRZ-to-RZ format conversion can also be demonstrated in a semiconductor optical amplifier under a backward dark-optical-comb injection with its duty-cycle 70%, which is obtained by reshaping from the received data clock at 10 GHz. The incoming optical NRZ data-stream is transformed into a pulsed RZ data-stream with its duty-cycle, rms timing jitter, and conversion gain of 15%, 4ps, and 3dB, respectively. In contrast to the FPLD, the SOA based NRZ-to-RZ converter exhibits an enhanced extinction ratio from 7 to 13 dB, and BER of 10 -13 at -18.5 dBm. In particular, the power penalty of the received RZ data-stream has greatly improved by 5 dB as compared to that obtained from FPLD.

  12. Logic Reasoning

    Institute of Scientific and Technical Information of China (English)

    小雨

    2006-01-01

    A teacher was giving her pu- pils a lesson on logic(逻辑).“Here is the situation(情景),”she said,“a man is stand- ing up in a boat in the middle of a river,fishing.He loses his bal- ance(平衡),falls in,and begins splashing(泼水)and yelling(叫喊)for help.His wife hears the commotion(喧闹),knows that he can’t swim,and runs down to the bank (河岸).Why did she run to the bank?” A girl raised her hand and asked,“To draw out(提取)all of his savings(存款).”

  13. Method of developing all-optical trinary JK, D-type, and T-type flip-flops using semiconductor optical amplifiers.

    Science.gov (United States)

    Garai, Sisir Kumar

    2012-04-10

    To meet the demand of very fast and agile optical networks, the optical processors in a network system should have a very fast execution rate, large information handling, and large information storage capacities. Multivalued logic operations and multistate optical flip-flops are the basic building blocks for such fast running optical computing and data processing systems. In the past two decades, many methods of implementing all-optical flip-flops have been proposed. Most of these suffer from speed limitations because of the low switching response of active devices. The frequency encoding technique has been used because of its many advantages. It can preserve its identity throughout data communication irrespective of loss of light energy due to reflection, refraction, attenuation, etc. The action of polarization-rotation-based very fast switching of semiconductor optical amplifiers increases processing speed. At the same time, tristate optical flip-flops increase information handling capacity.

  14. Properties of Measure-based Fuzzy Logic

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Measure-based fuzzy logic, which is constructed on the basis of eight axioms, is a seemingly powerful fuzzy logic. It possesses several remarkable properties. (1) It is an extended Boolean logic, satisfying all the properties of Boolean algebra, including the law of excluded middle and the law of contradiction. (2) It is conditional. Conditional membership functions play an important role in this logic. (3) The negation operator is not independently defined with the conjunction and disjunction operators, but on the contrary, it is derived from them. (4) Zadehs fuzzy logic is included in it as a particular case. (5) It gives more hints to the relationship between fuzzy logic and probability logic.

  15. All-optical four-state magnetization reversal in (Ga,Mn)As ferromagnetic semiconductors

    CERN Document Server

    Kapetanakis, M D; Piermarocchi, C; Wang, J; Perakis, I E

    2011-01-01

    Using density matrix equations of motion and a tight-binding band calculation, we predict all-optical switching between four metastable magnetic states of (III,Mn)As ferromagnets. This switching is initiated non-thermally within 100fs, during nonlinear coherent photoexcitation. For a single optical pulse, magnetization reversal is completed after $\\sim$100 ps and controlled by the coherent femtosecond photoexcitation. Our predicted switching comes from magnetic nonlinearities triggered by a femtosecond magnetization tilt that is sensitive to un--adiabatic light--induced spin interactions.

  16. 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.

  17. All-optical tailoring of single-photon spectra in a quantum-dot microcavity system

    CERN Document Server

    Breddermann, Dominik; Binder, Rolf; Zrenner, Artur; Schumacher, Stefan

    2016-01-01

    Semiconductor quantum-dot cavity systems are promising sources for solid-state based on-demand generation of single photons for quantum communication. Commonly, the spectral characteristics of the emitted single photon are fixed by system properties such as electronic transition energies and spectral properties of the cavity. In the present work we study single-photon generation from the quantum-dot biexciton through a partly stimulated non-degenerate two-photon emission. We show that frequency and linewidth of the single photon can be fully controlled by the stimulating laser pulse, ultimately allowing for efficient all-optical spectral shaping of the single photon.

  18. Linear all-optical signal processing using silicon micro-ring resonators

    DEFF Research Database (Denmark)

    Ding, Yunhong; Ou, Haiyan; Xu, Jing;

    2016-01-01

    Silicon micro-ring resonators (MRRs) are compact and versatile devices whose periodic frequency response can be exploited for a wide range of applications. In this paper, we review our recent work on linear all-optical signal processing applications using silicon MRRs as passive filters. We focus...... on applications such as modulation format conversion, differential phase-shift keying (DPSK) demodulation, modulation speed enhancement of directly modulated lasers (DMLs), and monocycle pulse generation. The possibility to implement polarization diversity circuits, which reduce the polarization dependence...

  19. Cavity electromagnetically induced transparency and all-optical switching using ion Coulomb crystals

    DEFF Research Database (Denmark)

    Albert, Magnus; Dantan, Aurelien Romain; Drewsen, Michael

    2011-01-01

    nonlinear interactions, such as those based on electromagnetic induced transparency (EIT)2, 3, 4, 5, 6, 9, 10, 11, 12. Here, we demonstrate for the first time EIT as well as all-optical EIT-based light switching using ion Coulomb crystals situated in an optical cavity. Changes from essentially full...... transmission to full absorption of a single photon probe field are achieved within unprecedentedly narrow EIT windows of a few tens of kilohertz. By applying a weak switching field, this allows us to demonstrate nearly perfect switching of the transmission of the probe field. The results represent important...

  20. Synthesis and characterization of azo-containing organometallic thin films for all optical switching applications

    Science.gov (United States)

    Gatri, R.; Fillaut, J.-L.; Mysliwiec, J.; Szukalski, A.; Bartkiewicz, S.; El-Ouazzani, H.; Guezguez, I.; Khammar, F.; Sahraoui, B.

    2012-05-01

    Novel photoresponsive materials based on azo-containing bifunctional ruthenium-acetylides have been synthesized. All optical switching based on the Optical Kerr Effect in the organometallic thin films based on ruthenium(II) acetylides containing an azobenzene moiety as a photochromic unit in the main pi-conjugated system dispersed in a poly(methyl methacrylate) matrix has been observed. The excitation beam was delivered from a picosecond laser at wavelength 532 nm while dynamics of induced sample birefringence was probed by a non-absorbed linearly polarized beam of cw He-Ne laser (632.8 nm). The influence of ruthenium part on dynamics of molecular motions has been shown.

  1. 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.

  2. All-optical radiation reaction at 10²¹ W/cm².

    Science.gov (United States)

    Vranic, M; Martins, J L; Vieira, J; Fonseca, R A; Silva, L O

    2014-09-26

    Using full-scale 3D particle-in-cell simulations we show that the radiation reaction dominated regime can be reached in an all-optical configuration through the collision of a ~1 GeV laser wakefield accelerated electron bunch with a counterpropagating laser pulse. In this configuration the radiation reaction significantly reduces the energy of the particle bunch, thus providing clear experimental signatures for the process with currently available lasers. We also show that the transition between the classical and quantum radiation reaction could be investigated in the same configuration with laser intensities of 10²³ W/cm².

  3. Simple nonlinear interferometer-based all-optical thresholder and its applications for optical CDMA.

    Science.gov (United States)

    Kravtsov, Konstantin; Prucnal, Paul R; Bubnov, Mikhail M

    2007-10-01

    We present an experimental demonstration of an ultrafast all-optical thresholder based on a nonlinear Sagnac interferometer. The proposed design is intended for operation at very small nonlinear phase shifts. Therefore, it requires an in-loop nonlinearity lower than for the classical nonlinear loop mirror scheme. Only 15 meters of conventional (non-holey) silica-based fiber is used as a nonlinear element. The proposed thresholder is polarization insensitive and is good for multi-wavelength operation, meeting all the requirements for autocorrelation detection in various optical CDMA communication systems. The observed cubic transfer function is superior to the quadratic transfer function of second harmonic generation-based thresholders.

  4. All-optical detection of magnetization precession in tunnel junctions under applied voltage

    Science.gov (United States)

    Sasaki, Yuta; Suzuki, Kazuya; Sugihara, Atsushi; Kamimaki, Akira; Iihama, Satoshi; Ando, Yasuo; Mizukami, Shigemi

    2017-02-01

    An all-optical time-resolved magneto-optical Kerr effect measurement of a micron-sized tunnel junction with a CoFeB electrode was performed. The femtosecond (fs) laser-induced magnetization precession was clearly observed at various magnetic field angles. The frequency f and relaxation time τ of the magnetization precession varied with the voltage applied via a MgO barrier. The precession dynamics were in accordance with Kittel’s ferromagnetic resonance mode, and the voltage-induced changes in f and τ were well explained by the voltage-induced change in the perpendicular magnetic anisotropy of -36 fJ/Vm.

  5. All-optical subdiffraction multilevel data encoding onto azo-polymeric thin films

    Science.gov (United States)

    Savoini, Matteo; Biagioni, Paolo; Duò, Lamberto; Finazzi, Marco

    2009-03-01

    By exploiting photo-induced reorientation in azo-polymer thin films, we demonstrate all-optical polarization-encoded information storage with a scanning near-field optical microscope. In the writing routine, 5-level bits are created by associating different bit values to different birefringence directions, induced in the polymer after illumination with linearly polarized light. The reading routine is then performed by implementing polarization-modulation techniques on the same near-field microscope, in order to measure the encoded birefringence direction.

  6. Effects on Semiconductor Optical Amplifier Gain Quality for Applications in Advanced All-optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Riyam A. Johni

    2014-04-01

    Full Text Available Semiconductor optical amplifiers are strong candidates to replace traditional erbium-doped-fibre-amplifiers in future all-optical networks by virtue of their proven functional capabilities, in addition to gain. They are also smaller, cheaper and easier to integrate than fibre amplifiers. This study summarizes the gain quality of the semiconductor optical amplifier with varying effects such as input power, bias current and wavelength and data rate. The results reported herein show high quality gain, coupled with accept ably low noise figure values.

  7. Improving the All-Optical Response of SOAs Using a Modulated Holding Signal

    DEFF Research Database (Denmark)

    Bischoff, Svend; Nielsen, Mads Lønstrup; Mørk, Jesper

    2004-01-01

    A method for increasing the all-optical modulation bandwidth of semiconductor optical amplifiers (SOAs) by use of a cross-gain-modulated (XGM) holding signal is suggested and analyzed. The bandwidth improvement is numerically demonstrated by studying wavelength conversion in an SOA-based Mach......-Zehnder interferometer (MZI) at 160 and 40 Gb/s. The new scheme is predicted to improve the extinction ratio and the minimum mark output power, as well as to reduce the amplitude jitter of the wavelength converted signal....

  8. All-optical modulation in wavelength-sized epsilon-near-zero media

    CERN Document Server

    Ciattoni, Alessandro; Rizza, Carlo

    2016-01-01

    We investigate the interaction of two pulses (pump and probe) scattered by a nonlinear epsilon-near-zero (ENZ) slab whose thickness is comparable with the ENZ wavelength. We show that when the probe has a narrow spectrum localized around the ENZ wavelength its transmission is dramatically affected by the intensity of the pump. Conversely, if the probe is not in the ENZ regime, its propagation is not noticeably affected by the pump. Such all-optical modulation is due to the oversensitive character of the ENZ regime and it is so efficient to even occur in a wavelength thick slab.

  9. One single trapped and laser cooled radium ion: Towards an all-optical atomic clock

    Energy Technology Data Exchange (ETDEWEB)

    Versolato, Oscar; Wansbeek, Lotje; Willmann, Lorenz; Timmermans, Rob; Jungmann, Klaus [KVI, University of Groningen (Netherlands)

    2008-07-01

    One single trapped radium ion is an ideal candidate for an all-optical frequency standard (*clock*). This system provides a long coherence time and tractable systematics. If the ion is laser cooled to the Lamb-Dicke regime, first order Doppler shifts are eliminated. Ultra-narrow transitions in radium ions provide an excellent basis for such a high stability clock, using commercially available semiconductor lasers in the visible regime. In certain odd isotopes of radium, the nuclear electric quadrupole shift is absent. Further, the radium ion is an excellent candidate for a high sensitivity experiment to search for a time variation of the finestructure constant.

  10. All-optical $\\mathcal{PT}$-symmetric amplitude to phase modulator

    CERN Document Server

    Gutiérrez, Oscar Ignacio Zaragoza; Rodríguez-Lara, B M

    2015-01-01

    We study electromagnetic field propagation through a planar three-waveguide coupler with linear gain and loss, in a configuration that is the optical analog of a quantum $\\mathcal{PT}$-symmetric system, and provide its closed-form analytic propagator. At an specific propagation length, we show that the device provides all-optical amplitude to phase modulation with a $\\pi$ modulation range, if an extra binary phase is allowed in the reference signal, as well as phase to amplitude modulation, with an amplitude modulation range that depends linearly on the gain-to-coupling ratio of the system.

  11. All-optical chaotic MQW laser repeater for long-haul chaotic communications

    Institute of Scientific and Technical Information of China (English)

    Senlin Yan

    2005-01-01

    We present an all-optical chaotic multi-quantum-well (MQW) laser repeater system to be used in long-haul chaotic communications. Chaotic synchronization is achieved among transmitter, repeater, and receiver. Chaotic repeater communications with a sinusoidal signal of 0.2-GHz modulation frequency and a digital signal of 0.4-Gb/s bit rate are numerically simulated, respectively. Calculation results illustrate that the signals are well decoded by the chaotic repeaters. Its bandwidth and the characteristics at much high bit rate are also analyzed. Simulation shows that the repeater can improve decoding quality, especially in higher bit rate chaotic communications.

  12. 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...... realistic investigation of the switching performance requires longer random pulse sequences, since detrimental effects may accumulate over time scales longer than one pulse duration. This has been investigated for switches based on semiconductor optical amplifiers [3], but in this work the focus...

  13. Spectral amplitude and phase measurement of ultrafast pulses using all-optical differential tomography.

    Science.gov (United States)

    Londero, Pablo; Kuzucu, Onur; Gaeta, Alexander L

    2011-05-01

    We demonstrate a simple, all-optical, fiber-based method for characterizing the spectral amplitude and phase of ultrafast pulses using a differential tomographic measurement realized via four-wave mixing. The technique is applied to subpicosecond pulses in the C-band of the telecommunication spectrum. Characterization of amplified pulses and propagation through dispersive media is demonstrated and compared with autocorrelation measurements and calculated predictions. We show how our approach can be extended to larger bandwidths in similar systems, extending tomographic reconstruction of coherent fields to nearly an octave of bandwidth while maintaining a robust, waveguide-based geometry.

  14. Design of All-Optical Loadable and Erasable Memory Cell by LWI and EIT Effects

    Science.gov (United States)

    Abbasian, K.; Verki, N. G.; Rostami, A.

    2011-12-01

    We have designed a loadable and erasable all optical memory unit cell by using two coupled micro-ring resonators structure. To read out stored data we have created additional phase in the upper ring by electromagnetically induced transparency (EIT) phenomenon induced by inserted Λ-type three level quantum dots in the right hand half of the upper ring. Also, for compensating the fiber loss, we have used lasing without inversion (LWI) by inserted Y-type four level QDs in the left hand half of the both rings. This optical memory unit cell can work in only one photon-scale energy.

  15. All-optical switching in an open V-type atomic system

    Science.gov (United States)

    Jafarzadeh, H.

    2017-02-01

    In this paper, the optical bistability (OB) and absorption properties of a weak probe field in an open V-type three-level atomic system have been investigated. We found that the OB threshold could be reduced via spontaneously generated coherence (SGC), coherent and incoherent pump fields, atomic injection, and exit rates. We also found that the threshold intensity of OB in an open system was less than that in the closed system. The all-optical switching due to the OB has also been discussed.

  16. Mechanism of all-optical control of ferromagnetic multilayers with circularly polarized light

    CERN Document Server

    Medapalli, Rajasekhar; Kim, Dokyun; Quessab, Yassine; Monotoya, Sergio A; Kirilyuk, Andrei; Rasing, Theo; Kimel, Alexey V; Fullerton, Eric E

    2016-01-01

    Time-resolved imaging reveals that the helicity dependent all-optical switching (HD-AOS) of Co/Pt ferromagnetic multilayers proceeds by two stages. First one involves the helicity independent and stochastic nucleation of reversed magnetic domains. At the second stage circularly polarized light breaks the degeneracy between the magnetic domains and promotes the preferred direction of domain wall (DW) motion. The growth of the reversed domain from the nucleation cite, for a particular helicity, leads to full magnetic reversal. This study demonstrates a novel mechanism of HD-AOS mediated by the deterministic displacement of DWs.

  17. Dual correlated pumping scheme for phase noise preservation in all-optical wavelength conversion.

    Science.gov (United States)

    Anthur, Aravind P; Watts, Regan T; Shi, Kai; Carroll, John O'; Venkitesh, Deepa; Barry, Liam P

    2013-07-01

    We study the effect of transfer of phase noise in different four wave mixing schemes using a coherent phase noise measurement technique. The nature of phase noise transfer from the pump to the generated wavelengths is shown to be independent of the type of phase noise (1 / f or white noise frequency components). We then propose a novel scheme using dual correlated pumps to prevent the increase in phase noise in the conjugate wavelengths. The proposed scheme is experimentally verified by the all-optical wavelength conversion of a DQPSK signal at 10.7 GBaud.

  18. 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...... and a high-speed optical switch. In the experiment, WDM 10-Gb/s data packets are successfully routed with 1-dB power penalty at a bit-error rate of 10(-9)....

  19. All-optical photoacoustic imaging system using fiber ultrasound probe and hollow optical fiber bundle.

    Science.gov (United States)

    Miida, Yusuke; Matsuura, Yuji

    2013-09-23

    An all-optical 3D photoacoustic imaging probe that consists of an optical fiber probe for ultrasound detection and a bundle of hollow optical fibers for excitation of photoacoustic waves was developed. The fiber probe for ultrasound is based on a single-mode optical fiber with a thin polymer film attached to the output end surface that works as a Fabry Perot etalon. The input end of the hollow fiber bundle is aligned so that each fiber in the bundle is sequentially excited. A thin and flexible probe can be obtained because the probe system does not have a scanning mechanism at the distal end.

  20. Multi-band radio over fiber system with all-optical halfwave rectification, transmission and frequency down-conversion

    DEFF Research Database (Denmark)

    Prince, Kamau; Tafur Monroy, Idelfonso

    2011-01-01

    We introduce a novel application of all-optical half-wave rectification in the transportation and delivery of multi-frequency radio-over fiber signals. System evaluation was performed of transmission over various optical fiber types and all-optical envelope detection was implemented to achieve...

  1. All-optical signal processing of OTDM and OFDM signals based on time-domain Optical Fourier Transformation

    DEFF Research Database (Denmark)

    Clausen, Anders; Guan, Pengyu; Mulvad, Hans Christian Hansen

    2014-01-01

    All-optical time-domain Optical Fourier Transformation utilised for signal processing of ultra-high-speed OTDM signals and OFDM signals will be presented.......All-optical time-domain Optical Fourier Transformation utilised for signal processing of ultra-high-speed OTDM signals and OFDM signals will be presented....

  2. Paraconsistent Computational Logic

    DEFF Research Database (Denmark)

    Jensen, Andreas Schmidt; Villadsen, Jørgen

    2012-01-01

    In classical logic everything follows from inconsistency and this makes classical logic problematic in areas of computer science where contradictions seem unavoidable. We describe a many-valued paraconsistent logic, discuss the truth tables and include a small case study.......In classical logic everything follows from inconsistency and this makes classical logic problematic in areas of computer science where contradictions seem unavoidable. We describe a many-valued paraconsistent logic, discuss the truth tables and include a small case study....

  3. Three-valued logics in modal logic

    NARCIS (Netherlands)

    Kooi, Barteld; Tamminga, Allard

    2013-01-01

    Every truth-functional three-valued propositional logic can be conservatively translated into the modal logic S5. We prove this claim constructively in two steps. First, we define a Translation Manual that converts any propositional formula of any three-valued logic into a modal formula. Second, we

  4. Nonlinear all-optical switch based on a white-light cavity

    Science.gov (United States)

    Li, Na; Xu, Jingping; Song, Ge; Zhu, Chengjie; Xie, Shuangyuan; Yang, Yaping; Zubairy, M. Suhail; Zhu, Shi-Yao

    2016-04-01

    It is well known that there is a bottleneck for nonlinear all-optical switching, namely, the switching power and the switching time cannot be lowered simultaneously. A lower switching power requires a resonator with a high quality (Q ) factor, but leads to a longer switching time. We propose to overcome this bottleneck by replacing the nonlinear cavity in such an all-optical switch by a white-light cavity. This can be done by doping three-level atoms in the ring resonator and applying incoherent pump and coherent driving fields on it. The white-light cavity possesses broadband resonance in a linear region. Therefore, for the incident pulse, a broad range of frequency components can take part in the nonlinear process, and so it requires lower power to achieve switching compared to the conventional ring resonator. On the other hand, the refractive index of a white-light cavity has negative dispersion, leading to a fast group velocity. This results in a shorter time to build up the resonant response, yielding a short switching time.

  5. Ultrafast all-optical coherent control of single silicon vacancy colour centres in diamond

    Science.gov (United States)

    Becker, Jonas Nils; Görlitz, Johannes; Arend, Carsten; Markham, Matthew; Becher, Christoph

    2016-11-01

    Complete control of the state of a quantum bit (qubit) is a fundamental requirement for any quantum information processing (QIP) system. In this context, all-optical control techniques offer the advantage of a well-localized and potentially ultrafast manipulation of individual qubits in multi-qubit systems. Recently, the negatively charged silicon vacancy centre (SiV-) in diamond has emerged as a novel promising system for QIP due to its superior spectral properties and advantageous electronic structure, offering an optically accessible Λ-type level system with large orbital splittings. Here, we report on all-optical resonant as well as Raman-based coherent control of a single SiV- using ultrafast pulses as short as 1 ps, significantly faster than the centre's phonon-limited ground state coherence time of about 40 ns. These measurements prove the accessibility of a complete set of single-qubit operations relying solely on optical fields and pave the way for high-speed QIP applications using SiV- centres.

  6. Engineered materials for all-optical helicity-dependent magnetic switching

    Science.gov (United States)

    Mangin, S.; Gottwald, M.; Lambert, C.-H.; Steil, D.; Uhlíř, V.; Pang, L.; Hehn, M.; Alebrand, S.; Cinchetti, M.; Malinowski, G.; Fainman, Y.; Aeschlimann, M.; Fullerton, E. E.

    2014-03-01

    The possibility of manipulating magnetic systems without applied magnetic fields have attracted growing attention over the past fifteen years. The low-power manipulation of the magnetization, preferably at ultrashort timescales, has become a fundamental challenge with implications for future magnetic information memory and storage technologies. Here we explore the optical manipulation of the magnetization in engineered magnetic materials. We demonstrate that all-optical helicity-dependent switching (AO-HDS) can be observed not only in selected rare earth-transition metal (RE-TM) alloy films but also in a much broader variety of materials, including RE-TM alloys, multilayers and heterostructures. We further show that RE-free Co-Ir-based synthetic ferrimagnetic heterostructures designed to mimic the magnetic properties of RE-TM alloys also exhibit AO-HDS. These results challenge present theories of AO-HDS and provide a pathway to engineering materials for future applications based on all-optical control of magnetic order.

  7. All-optical link for direct comparison of distant optical clocks

    CERN Document Server

    Fujieda, Miho; Nagano, Shigeo; Yamaguchi, Atsushi; Hachisu, Hidekazu; Ido, Tetsuya

    2011-01-01

    We developed an all-optical link system for making remote comparisons of two distant ultra-stable optical clocks. An optical carrier transfer system based on a fiber interferometer was employed to compensate the phase noise accumulated during the propagation through a fiber link. Transfer stabilities of $2\\times10^{-15}$ at 1 second and $4\\times10^{-18}$ at 1000 seconds were achieved in a 90-km link. An active polarization control system was additionally introduced to maintain the transmitted light in an adequate polarization, and consequently, a stable and reliable comparison was accomplished. The instabilities of the all-optical link system, including those of the erbium doped fiber amplifiers (EDFAs) which are free from phase-noise compensation, were below $2\\times10^{-15}$ at 1 second and $7\\times10^{-17}$ at 1000 seconds. The system was available for the direct comparison of two distant $^{87}$Sr lattice clocks via an urban fiber link of 60 km. This technique will be essential for the measuring the repro...

  8. All-Optical Formation of Coherent Dark States of Silicon-Vacancy Spins in Diamond

    Science.gov (United States)

    Pingault, Benjamin; Becker, Jonas N.; Schulte, Carsten H. H.; Arend, Carsten; Hepp, Christian; Godde, Tillmann; Tartakovskii, Alexander I.; Markham, Matthew; Becher, Christoph; Atatüre, Mete

    2014-12-01

    Spin impurities in diamond can be versatile tools for a wide range of solid-state-based quantum technologies, but finding spin impurities that offer sufficient quality in both photonic and spin properties remains a challenge for this pursuit. The silicon-vacancy center has recently attracted much interest because of its spin-accessible optical transitions and the quality of its optical spectrum. Complementing these properties, spin coherence is essential for the suitability of this center as a spin-photon quantum interface. Here, we report all-optical generation of coherent superpositions of spin states in the ground state of a negatively charged silicon-vacancy center using coherent population trapping. Our measurements reveal a characteristic spin coherence time, T2* , exceeding 45 nanoseconds at 4 K. We further investigate the role of phonon-mediated coupling between orbital states as a source of irreversible decoherence. Our results indicate the feasibility of all-optical coherent control of silicon-vacancy spins using ultrafast laser pulses.

  9. Design of an All-Optical Network Based on LCoS Technologies

    Science.gov (United States)

    Cheng, Yuh-Jiuh; Shiau, Yhi

    2016-06-01

    In this paper, an all-optical network composed of the ROADMs (reconfigurable optical add-drop multiplexer), L2/L3 optical packet switches, and the fiber optical cross-connection for fiber scheduling and measurement based on LCoS (liquid crystal on silicon) technologies is proposed. The L2/L3 optical packet switches are designed with optical output buffers. Only the header of optical packets is converted to electronic signals to control the wavelength of input ports and the packet payloads can be transparently destined to their output ports. An optical output buffer is designed to queue the packets when more than one incoming packet should reach to the same destination output port. For preserving service-packet sequencing and fairness of routing sequence, a priority scheme and a round-robin algorithm are adopted at the optical output buffer. The wavelength of input ports is designed for routing incoming packets using LCoS technologies. Finally, the proposed OFS (optical flow switch) with input buffers can quickly transfer the big data to the output ports and the main purpose of the OFS is to reduce the number of wavelength reflections. The all-optical content delivery network is comprised of the OFSs for a large amount of audio and video data transmissions in the future.

  10. M-Burst: A Framework of SRLG Failure Localization in All-Optical Networks

    KAUST Repository

    Ali, Mohammed L.

    2012-07-27

    Fast and unambiguous failure localization for shared risk link groups (SRLGs) with multiple links is essential for building a fully survivable and functional transparent all-optical mesh network. Monitoring trails (m-trails) have been proposed as an effective approach to achieve this goal. However, each m-trail traverses through each link by constantly taking a wavelength channel, causing a significant amount of resource consumption. In this paper, a novel framework of all-optical monitoring for SRLG failure localization is proposed. We investigate the feasibility of periodically launching optical bursts along each m-trail instead of assigning it a dedicated supervisory lightpath to probe the set of fiber segments along the m-trail, aiming to achieve a graceful compromise between resource consumption and failure localization latency. This paper defines the proposed framework and highlights the relevant issues regarding its feasibility. We provide theoretical justifications of the scheme. As a proof of concept, we formulate the optimal burst scheduling problem via an integer linear program (ILP) and implement the method in networks of all possible SRLGs with up to d=3 links. A heuristic method is also proposed and implemented for multiple-link SRLG failure localization, keeping all the assumptions the same as in the ILP method. Numerical results for small networks show that the scheme is able to localize single-link and multiple-link SRLG failures unambiguously with a very small amount of failure localization latency.

  11. Electrical characterization of all-optical helicity-dependent switching in ferromagnetic Hall crosses

    Science.gov (United States)

    El Hadri, M. S.; Pirro, P.; Lambert, C.-H.; Bergeard, N.; Petit-Watelot, S.; Hehn, M.; Malinowski, G.; Montaigne, F.; Quessab, Y.; Medapalli, R.; Fullerton, E. E.; Mangin, S.

    2016-02-01

    We present an experimental study of all-optical helicity-dependent switching (AO-HDS) of ferromagnetic Pt/Co/Pt heterostructures with perpendicular magnetic anisotropy. The sample is patterned into a Hall cross and the AO-HDS is measured via the anomalous Hall effect. This all-electrical probing of the magnetization during AO-HDS enables a statistical quantification of the switching ratio for different laser parameters, such as the threshold power to achieve AO-HDS and the exposure time needed to reach complete switching at a given laser power. We find that the AO-HDS is a cumulative process, a certain number of optical pulses is needed to obtain a full and reproducible helicity-dependent switching. The deterministic switching of the ferromagnetic Pt/Co/Pt Hall cross provides a full "opto-spintronic device," where the remanent magnetization can be all-optically and reproducibly written and erased without the need of an external magnetic field.

  12. High speed all optical Nyquist signal generation and full-band coherent detection.

    Science.gov (United States)

    Zhang, Junwen; Yu, Jianjun; Fang, Yuan; Chi, Nan

    2014-08-21

    Spectrum efficient data transmission is of key interest for high capacity optical communication systems considering the limited available bandwidth. Transmission of the high speed signal with higher-order modulation formats within the Nyquist bandwidth using coherent detection brings attractive performance advantages. However, high speed Nyquist signal generation with high order modulation formats is challenging. Electrical Nyquist pulse generation is restricted by the limited sampling rate and processor capacities of digital-to-analog convertor devices, while the optical Nyquist signals can provide a much higher symbol rate using time domain multiplexing method. However, most optical Nyquist signals are based on direct detection with simple modulation formats. Here we report the first experimental demonstration of high speed all optical Nyquist signal generation based on Sinc-shaped pulse generation and time-division multiplexing with high level modulation format and full-band coherent detection. Our experiments demonstrate a highly flexible and compatible all optical high speed Nyquist signal generation and detection scheme for future fiber communication systems.

  13. Formation and all-optical control of optical patterns in semiconductor microcavities

    Science.gov (United States)

    Binder, R.; Tsang, C. Y.; Tse, Y. C.; Luk, M. H.; Kwong, N. H.; Chan, Chris K. P.; Leung, P. T.; Lewandowski, P.; Schumacher, Stefan; Lafont, O.; Baudin, E.; Tignon, J.

    2016-05-01

    Semiconductor microcavities offer a unique way to combine transient all-optical manipulation of GaAs quantum wells with the benefits of structural advantages of microcavities. In these systems, exciton-polaritons have dispersion relations with very small effective masses. This has enabled prominent effects, for example polaritonic Bose condensation, but it can also be exploited for the design of all-optical communication devices. The latter involves non-equilibrium phase transitions in the spatial arrangement of exciton-polaritons. We consider the case of optical pumping with normal incidence, yielding a spatially homogeneous distribution of exciton-polaritons in optical cavities containing the quantum wells. Exciton-exciton interactions can trigger instabilities if certain threshold behavior requirements are met. Such instabilities can lead, for example, to the spontaneous formation of hexagonal polariton lattices (corresponding to six-spot patterns in the far field), or to rolls (corresponding to two-spot far field patterns). The competition among these patterns can be controlled to a certain degree by applying control beams. In this paper, we summarize the theory of pattern formation and election in microcavities and illustrate the switching between patterns via simulation results.

  14. Optical resilient packet ring (O-RPR) based on all-optical buffering techniques

    Science.gov (United States)

    Wu, Chongqing; Sheng, Xingzhi; Fu, Songnian; Wei, Bin; Li, Yajie; Liu, Aiming

    2006-01-01

    This paper reports the progress of the 863 high-technology project of China "Optical Resilient Packet Ring (O-RPR) Based on All-optical Buffering Techniques". In this ring network, for the packet through an intermediate node the conversion of O/E/O is not needed in order to overcome the bottleneck of O/E/O. In all-optical node a Dual Loop Optical Buffer (DLOB) is used to revolve the collision between the packet, which pass through the node, and add packet from local user to ring. The principle of DLOB is introduced. The bit-rate of head of optical frame is lower than the bit-rate of payload in a packet, in order to increase the efficiency of transmission link. This paper will introduce the network topology, layers and the structure of optical node. It includes an optical splitter, optical delay line as input buffer, a SOA as optical switch, which switch the packet dropping down form the ring or pass through the node, a DLOB and an electric buffer. An ARM is used for regulation of different buffers. The experiment results of a demonstrate network including 3 nodes are given.

  15. Advances in Modal Logic

    DEFF Research Database (Denmark)

    Modal logic is a subject with ancient roots in the western logical tradition. Up until the last few generations, it was pursued mainly as a branch of philosophy. But in recent years, the subject has taken new directions with connections to topics in computer science and mathematics. This volume i...... epistemic logic, and the logic of evidence.......Modal logic is a subject with ancient roots in the western logical tradition. Up until the last few generations, it was pursued mainly as a branch of philosophy. But in recent years, the subject has taken new directions with connections to topics in computer science and mathematics. This volume...... is the proceedings of the conference of record in its fi eld, Advances in Modal Logic. Its contributions are state-of-the-art papers. The topics include decidability and complexity results for specifi c modal logics, proof theory of modal logic, logics for reasoning about time and space, provability logic, dynamic...

  16. Strong Completeness of Coalgebraic Modal Logics

    CERN Document Server

    Schröder, Lutz

    2009-01-01

    Canonical models are of central importance in modal logic, in particular as they witness strong completeness and hence compactness. While the canonical model construction is well understood for Kripke semantics, non-normal modal logics often present subtle difficulties - up to the point that canonical models may fail to exist, as is the case e.g. in most probabilistic logics. Here, we present a generic canonical model construction in the semantic framework of coalgebraic modal logic, which pinpoints coherence conditions between syntax and semantics of modal logics that guarantee strong completeness. We apply this method to reconstruct canonical model theorems that are either known or folklore, and moreover instantiate our method to obtain new strong completeness results. In particular, we prove strong completeness of graded modal logic with finite multiplicities, and of the modal logic of exact probabilities.

  17. Large-scale photonic integration for advanced all-optical routing functions

    Science.gov (United States)

    Nicholes, Steven C.

    Advanced InP-based photonic integrated circuits are a critical technology to manage the increasing bandwidth demands of next-generation all-optical networks. Integrating many of the discrete functions required in optical networks into a single device provides a reduction in system footprint and optical losses by eliminating the fiber coupling junctions between components. This translates directly into increased system reliability and cost savings. Although many key network components have been realized via InP-based monolithic integration over the years, truly large-scale photonic ICs have only recently emerged in the marketplace. This lag-time has been mostly due to historically low device yields. In all-optical routing applications, large-scale photonic ICs may be able to address two of the key roadblocks associated with scaling modern electronic routers to higher capacities---namely, power and size. If the functions of dynamic wavelength conversion and routing are moved to the optical layer, we can eliminate the need for power-hungry optical-to-electrical (O/E) and electrical-to-optical (E/O) data conversions at each router node. Additionally, large-scale photonic ICs could reduce the footprint of such a system by combining the similar functions of each port onto a single chip. However, robust design and manufacturing techniques that will enable high-yield production of these chips must be developed. In this work, we demonstrate a monolithic tunable optical router (MOTOR) chip consisting of an array of eight 40-Gbps wavelength converters and a passive arrayed-waveguide grating router that functions as the packet-forwarding switch fabric of an all-optical router. The device represents one of the most complex InP photonic ICs ever reported, with more than 200 integrated functional elements in a single chip. Single-channel 40 Gbps wavelength conversion and channel switching using 231-1 PRBS data showed a power penalty as low as 4.5 dB with less than 2 W drive power

  18. Probabilistic Dynamic Epistemic Logic

    NARCIS (Netherlands)

    Kooi, B.P.

    2003-01-01

    In this paper I combine the dynamic epistemic logic of Gerbrandy (1999) with the probabilistic logic of Fagin and Halpern (1999). The result is a new probabilistic dynamic epistemic logic, a logic for reasoning about probability, information, and information change that takes higher order informatio

  19. Ultra-low phase noise all-optical microwave generation setup based on commercial devices

    CERN Document Server

    Didier, A; Grop, S; Dubois, B; Bigler, E; Rubiola, E; Lacroûte, C; Kersalé, Y

    2015-01-01

    In this paper, we present a very simple design based on commercial devices for the all-optical generation of ultra-low phase noise microwave signals. A commercial, fibered femtosecond laser is locked to a laser that is stabilized to a commercial ULE Fabry-Perot cavity. The 10 GHz microwave signal extracted from the femtosecond laser output exhibits a single sideband phase noise $\\mathcal{L}(f)=-104 \\ \\mathrm{dBc}/\\mathrm{Hz}$ at 1 Hz Fourier frequency, at the level of the best value obtained with such "microwave photonics" laboratory experiments \\cite{Fortier2011}. Close-to-the-carrier ultra-low phase noise microwave signals will now be available in laboratories outside the frequency metrology field, opening up new possibilities in various domains.

  20. 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...

  1. Chip-integrated all-optical diode based on nonlinear plasmonic nanocavities covered with multicomponent nanocomposite

    Science.gov (United States)

    Chai, Zhen; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2017-01-01

    Ultracompact chip-integrated all-optical diode is realized experimentally in a plasmonic microstructure, consisting of a plasmonic waveguide side-coupled two asymmetric plasmonic composite nanocavities covered with a multicomponent nanocomposite layer, formed directly in a plasmonic circuit. Extremely large optical nonlinearity enhancement is obtained for the multicomponent nanocomposite cover layer, originating from resonant excitation, slow-light effect, and field enhancement effect. Nonreciprocal transmission was achieved based on the difference in the shift magnitude of the transparency window centers of two asymmetric plasmonic nanocavities induced by the signal light, itself, for the forward and backward propagation cases. An ultralow threshold incident light power of 145 μW (corresponding to a threshold intensity of 570 kW/cm2) is realized, which is reduced by seven orders of magnitude compared with previous reports. An ultrasmall feature size of 2 μm and a transmission contrast ratio of 15 dB are obtained simultaneously.

  2. All-optically integrated multimodality imaging system: combined photoacoustic microscopy, optical coherence tomography, and fluorescence imaging

    Science.gov (United States)

    Chen, Zhongjiang; Yang, Sihua; Xing, Da

    2016-10-01

    We have developed a multimodality imaging system by optically integrating all-optical photoacoustic microscopy (AOPAM), optical coherence tomography (OCT) and fluorescence microscopy (FLM) to provide complementary information including optical absorption, optical back-scattering and fluorescence contrast of biological tissue. By sharing the same low-coherence Michelson interferometer, AOPAM and OCT could be organically optically combined to obtain the absorption and scattering information of the biological tissues. Also, owing to using the same laser source and objective lens, intrinsically registered photoacoustic and fluorescence signals are obtained to present the radiative and nonradiative transition process of absorption. Simultaneously photoacoustic angiography, tissue structure and fluorescence molecular in vivo images of mouse ear were acquired to demonstrate the capabilities of the optically integrated trimodality imaging system, which can present more information to study tumor angiogenesis, vasculature, anatomical structure and microenvironments in vivo.

  3. 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.

  4. All-Optical Photorefractive Effect in Bihole-Transporting System Polymeric Composites

    Institute of Scientific and Technical Information of China (English)

    HUANG Mao-Mao; ZHOU Qi-Feng; CHEN Zhi-Jian; ZHANG Jie; WEI Qun; LIU Yi-Hong; GONG Qi-Huang; BAI Yao-Wen; CHEN Xiao-Fang; WAN Xin-Hua

    2004-01-01

    Photorefractive (PR) composites based on poly(N-vinylcarbozale) and azobenzene have been fabricated. Two beam-coupling and four-wave-mixing phenomena were observed in the absence of an external electric field or prepoling. The maximum two-beam-coupling gain coefficient and the refractive index modulation were measured to be 79 cm-1 and 2.2 × 10-4 respectively. The all-optical-PR phenomenon is explained based on the photoassisted poling of the azo dye by the synergism of the photoisomerization and the longitudinal electric field due to longitudinal intensity gradient of writing light beams. The bi-hole-transporting system provides more chargecarrier traps resulting in improvement of PR performance.

  5. Orientation of azobenzene molecules in polymer films induced by all-optical poling

    Institute of Scientific and Technical Information of China (English)

    Xiaoxia Zhong(钟晓霞); Shouyu Luo(罗售余); Xiuqin Yu(虞秀琴); Qu Li(李劬); Yingli Chen(陈英礼); Yu Sui(隋郁); Jie Yin(印杰)

    2003-01-01

    A model of the alignment of azobenzene molecules in polymer film induced by all-optical poling is proposedand verified by experiment. We found that when the writing beams of frequencies ω and 2ω are both linearlypolarized with their polarization directions parallel to each other, azobenzene molecules tend to reorientto the direction perpendicular to the writing beams polarization. At the end of the writing process, moremolecules orient to the direction perpendicular to the writing beams polarization than those which orientto the parallel direction. The alignment of molecules parallel or perpendicular to the polarization of thewriting beams is characteristic of polarity or no polarity, respectively. The alignment of molecules alongthe polarization of writing beams results in the second order nonlinearity in the polymer film. Accordingto the model, a new method to improve the optical poling efficiency is put forward.

  6. Nonlinear Transient Dynamics of Photoexcited Silicon Nanoantenna for Ultrafast All-Optical Signal Processing

    CERN Document Server

    Baranov, Denis G; Milichko, Valentin A; Kudryashov, Sergey I; Krasnok, Alexander E; Belov, Pavel A

    2016-01-01

    Optically generated electron-hole plasma in high-index dielectric nanostructures was demonstrated as a means of tuning of their optical properties. However, until now an ultrafast operation regime of such plasma driven nanostructures has not been attained. Here, we perform pump-probe experiments with resonant silicon nanoparticles and report on dense optical plasma generation near the magnetic dipole resonance with ultrafast (about 2.5 ps) relaxation rate. Basing on experimental results, we develop an analytical model describing transient response of a nanocrystalline silicon nanoparticle to an intense laser pulse and show theoretically that plasma induced optical nonlinearity leads to ultrafast reconfiguration of the scattering power pattern. We demonstrate 100 fs switching to unidirectional scattering regime upon irradiation of the nanoparticle by an intense femtosecond pulse. Our work lays the foundation for developing ultracompact and ultrafast all-optical signal processing devices.

  7. All-optical ultrafast switching of Si woodpile photonic band gap crystals

    CERN Document Server

    Euser, T G; Fleming, J G; Gralak, B; Polman, Albert; Vos, W L; Euser, Tijmen G.; Molenaar, Adriaan J.; Gralak, Boris; Polman, Albert; Vos, Willem L.

    2006-01-01

    We present ultrafast all-optical switching measurements of Si woodpile photonic band gap crystals at telecom frequencies. The crystals are homogeneously excited by a two-photon process. We probe the switching by measuring reflectivity over broad frequency ranges as a function of time. At short delay times, we observe that the photonic gap becomes narrower than in the unswitched case. After 1 ps, the complete gap has shifted to higher frequencies. This intricate behavior is the result of competing refractive index changes due to the electronic Kerr effect and to optically excited free carriers. The frequency shift of the band gap as a function of pump intensity agrees well with Fourier modal method calculations with no freely adjustable parameters.

  8. Robustness estimation of software-synchronized all-optical sampling for fiber communication systems

    Institute of Scientific and Technical Information of China (English)

    Aiying Yang; Xiangyu Wu; Yu'nan Sun

    2009-01-01

    The robustness of the software-synchronized all-optical sampling for optical performance monitoring is estimated for 10-Gb/s fiber communication systems. It reveals that the software-synchronized algorithm is sensitive to the signal degradation caused by chromatic dispersion and nonlinearity in optical fibers. The influence of timing jitter and amplitude fluctuation of the sampling pulses is also investigated. It is found that stringent requirements are imposed on the quality of the sampling pulse and the tolerance of l-dB Q penalty is measured. Considering the practically available optical sampling pulse sources, the results indicate that the amplitude fluctuation of the sampling pulses has the dominant impacts on the software-synchronized method.

  9. Continuous all-optical deceleration and single-photon cooling of molecular beams

    CERN Document Server

    Jayich, A M; Hummon, M T; Porto, J V; Campbell, W C

    2013-01-01

    Ultracold molecular gases are promising as an avenue to rich many-body physics, quantum chemistry, quantum information, and precision measurements. This richness, which flows from the complex internal structure of molecules, makes the creation of ultracold molecular gases using traditional methods (laser plus evaporative cooling) a challenge, in particular due to the spontaneous decay of molecules into dark states. We propose a way to circumvent this key bottleneck using an all-optical method for decelerating molecules using stimulated absorption and emission with a single ultrafast laser. We further describe single-photon cooling of the decelerating molecules that exploits their high dark state pumping rates, turning the principal obstacle to molecular laser cooling into an advantage. Cooling and deceleration may be applied simultaneously and continuously to load molecules into a trap. We discuss implementation details including multi-level numerical simulations of strontium monohydride (SrH). These techniqu...

  10. 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.

  11. Tunable all-optical devices based on liquid-filled photonic crystal fibers

    DEFF Research Database (Denmark)

    Rosberg, Christian Romer; Bennet, Francis; Neshev, Dragomir N.;

    of discrete and nonlinear light propagation in extended two-dimensional periodic systems. We experimentally demonstrate strongly tunable beam diffraction in a triangular waveguide array created by infiltration of a high index liquid into the cladding holes of a standard PCF, and employ the thermal...... nonlinearity of the liquid to achieve beam self-defocusing at higher light intensity. Based on the observed effects we devise a compact all-optical power limiter device with tunable characteristics. The use of commercially available PCFs in combination with liquid infiltration avoids the need for specialized...... high-precision fabrication procedures, and provides high tunability and nonlinearity at moderate laser powers while taking advantage of a compact experimental setup. The increasingly broad range of PCF structures available could stimulate further efforts in applying them in discrete nonlinear optics...

  12. All-optical hash code generation and verification for low latency communications.

    Science.gov (United States)

    Paquot, Yvan; Schröder, Jochen; Pelusi, Mark D; Eggleton, Benjamin J

    2013-10-07

    We introduce an all-optical, format transparent hash code generator and a hash comparator for data packets verification with low latency at high baudrate. The device is reconfigurable and able to generate hash codes based on arbitrary functions and perform the comparison directly in the optical domain. Hash codes are calculated with custom interferometric circuits implemented with a Fourier domain optical processor. A novel nonlinear scheme featuring multiple four-wave mixing processes in a single waveguide is implemented for simultaneous phase and amplitude comparison of the hash codes before and after transmission. We demonstrate the technique with single polarisation BPSK and QPSK signals up to a data rate of 80 Gb/s.

  13. All-optical switching and nonlinear optical properties of HBT in ethanol solution

    Institute of Scientific and Technical Information of China (English)

    Zheng Jia-Jin; Zhang Gui-Lan; Guo Yang-Xue; Li Xiang-Ping; Chen Wen-Ju

    2007-01-01

    This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-(2'-hydroxyphenyl)benzothiazole (HBT) in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer (ESIPT) effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.

  14. Multiport InP monolithically integrated all-optical wavelength router.

    Science.gov (United States)

    Zheng, Xiu; Raz, Oded; Calabretta, Nicola; Zhao, Dan; Lu, Rongguo; Liu, Yong

    2016-08-15

    An indium phosphide-based monolithically integrated wavelength router is demonstrated in this Letter. The wavelength router has four input ports and four output ports, which integrate four wavelength converters and a 4×4 arrayed-waveguide grating router. Each wavelength converter is achieved based on cross-gain modulation and cross-phase modulation effects in a semiconductor optical amplifier. Error-free wavelength switching for a non-return-to-zero 231-1 ps eudorandom binary sequence at 40 Gb/s data rate is performed. Both 1×4 and 3×1 all-optical routing functions of this chip are demonstrated for the first time with power penalties as low as 3.2 dB.

  15. Photonic Routing Systems Using All-optical, Hybrid Integrated Wavelength Converter Arrays

    Directory of Open Access Journals (Sweden)

    Leontios Stampoulidis

    2010-02-01

    Full Text Available The integration of a new generation of all-optical wavelength converters within European project ISTMUFINS has enabled the development of compact and multi-functional photonic processing systems. Here we present the realization of demanding functionalities required in high-capacity photonic routers using these highly integrated components including: Clock recovery, data/label recovery, wavelength routing and contention resolution; all implemented with multi-signal processing using a single photonic chip – a quadruple array of SOAMZI wavelength converters which occupies a chip area of only 15 x 58 mm2. In addition, we present the capability of the technology to build WDM signal processing systems with the simultaneous operation of four quad devices in a four wavelength burst-mode regenerator. Finally, the potential of the technology to provide photonic systems-onchip is demonstrated with the first hybrid integrated alloptical burst-mode receiver prototype.

  16. Silicon Nanowires for All-Optical Signal Processing in Optical Communication

    DEFF Research Database (Denmark)

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

    2012-01-01

    to the large mode mismatch and index mismatch. Both end-coupling and grating-coupling solution utilizing nano-structures were demonstrated with optimized coupling efficiencies, which make the silicon on-chip nanowire devices more practical for real optical communication systems.......Silicon (Si), the second most abundant element on earth, has dominated in microelectronics for many decades. It can also be used for photonic devices due to its transparency in the range of optical telecom wavelengths which will enable a platform for a monolithic integration of optics...... process. In the last four years, we investigated and demonstrated different ultra-fast all-optical nonlinear signal processing applications in silicon nanowires for optical time domain multiplexing (OTDM) systems, including wavelength conversion, signal regeneration, ultra-fast waveform sampling...

  17. Few-Photon All-Optical {\\pi} Phase modulation Based on a Double-{\\Lambda} System

    CERN Document Server

    Chen, Yen-Chun; Lo, Hsiang-Yu; Tsai, Bing-Ru; Yu, Ite A; Chen, Ying-Cheng; Chen, Yong-Fan

    2013-01-01

    We propose an efficient all-optical phase modulation based on a double-{\\Lambda} system and demonstrate a {\\pi} phase shift of a few-photon pulse induced by another few-photon pulse in cold rubidium atoms with this scheme. By changing the phases of the applied laser fields, one can control the property of the double-{\\Lambda} medium. This phase-dependent mechanism makes the double-{\\Lambda} system different form the conventional cross-Kerr-based system which only depends on the applied laser intensities. The proposed scheme provides a new route to generate strong nonlinear interactions between photons, and may have potential for applications in quantum information technologies.

  18. 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

    The performance of all-optical switches is a compromise between the achievable bandwidth of the switched signal and the energy requirement of the switching operation. In this work we consider a system consisting of a photonic crystal cavity coupled to two input and two output waveguides....... 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...... patterning effects, which occur on time scales that are longer than the bit period. Our analysis is based on a coupled mode theory, which allows for an extensive investigation of the influence of the system parameters on the switching dynamics. The analysis is shown to provide new insights into the ultrafast...

  19. A novel noninvasive all optical technique to monitor physiology of an exercising muscle

    Science.gov (United States)

    Saxena, Vishal; Marcu, Laura; Karunasiri, Gamani

    2008-11-01

    An all optical technique based on near-infrared spectroscopy and mid-infrared imaging (MIRI) is applied as a noninvasive, in vivo tool to monitor the vascular status of skeletal muscle and the physiological changes that occur during exercise. A near-infrared spectroscopy (NIRS) technique, namely, steady state diffuse optical spectroscopy (SSDOS) along with MIRI is applied for monitoring the changes in the values of tissue oxygenation and thermometry of an exercising muscle. The NIRS measurements are performed at five discrete wavelengths in a spectral window of 650-850 nm and MIRI is performed in a spectral window of 8-12 µm. The understanding of tissue oxygenation status and the behavior of the physiological parameters derived from thermometry may provide a useful insight into muscle physiology, therapeutic response and treatment.

  20. Investigation of all-optical regeneration based on self-phase modulation in microstructured fibers

    Institute of Scientific and Technical Information of China (English)

    WEI Yan-fen; XU Yong-zhao; Zhang Xia; HUANG Yong-qing; REN Xiao-min

    2007-01-01

    All-optical regeneration based on self-phase modulation in microstructured fibers is studied. The effects of pulse peak power into the fiber,pulse width and filter parameters on the performance of the regenerator are investigated. The effects of normal dispersion and anomalous dispersion of the microstructured fiber on optical regeneration are compared. The numerical results show that optical regeneration can be achieved by using microstructured fibers with normal dispersion or anomalous dispersion,but the normal dispersion decreases the oscillatory structure in the broadened spectra and obtain a better regenerator transfer function. In order to achieve optical regeneration,the input peak power into the microstructured fiber and the filter parameters need to meet certain requirements. By optimizing those parameters,a better regeneration result can be obtained.

  1. All-optical image processing and compression based on Haar wavelet transform.

    Science.gov (United States)

    Parca, Giorgia; Teixeira, Pedro; Teixeira, Antonio

    2013-04-20

    Fast data processing and compression methods based on wavelet transform are fundamental tools in the area of real-time 2D data/image analysis, enabling high definition applications and redundant data reduction. The need for information processing at high data rates motivates the efforts on exploiting the speed and the parallelism of the light for data analysis and compression. Among several schemes for optical wavelet transform implementation, the Haar transform offers simple design and fast computation, plus it can be easily implemented by optical planar interferometry. We present an all optical scheme based on an asymmetric couplers network for achieving fast image processing and compression in the optical domain. The implementation of Haar wavelet transform through a 3D passive structure is supported by theoretical formulation and simulations results. Asymmetrical coupler 3D network design and optimization are reported and Haar wavelet transform, including compression, was achieved, thus demonstrating the feasibility of our approach.

  2. Photo-generated THz antennas: All-optical control of plasmonic materials

    CERN Document Server

    Georgiou, Giorgos; Mulder, Peter; Bauhuis, Gerard J; Schermer, John J; Rivas, Jaime Gómez

    2013-01-01

    Localized surface plasmon polaritons in conducting structures give rise to enhancements of electromagnetic local fields and extinction efficiencies. Resonant conducting structures are conventionally fabricated with a fixed geometry that determines their plasmonic response. Here, we challenge this conventional approach by demonstrating the photo-generation of plasmonic materials (THz plasmonic antennas) on a flat semiconductor layer by the structured optical illumination through a spatial light modulator. Free charge carriers are photo-excited only on selected areas, which enables the definition of different plasmonic antennas on the same sample by simply changing the illumination pattern, thus without the need of physically structuring the sample. These results open a wide range of possibilities for an all-optical spatial and temporal control of resonances on plasmonic surfaces and the concomitant control of THz extinction and local field enhancements.

  3. All-optical switching in a continuously operated and strongly coupled atom-cavity system

    CERN Document Server

    Dutta, Sourav

    2016-01-01

    We experimentally demonstrate collective strong coupling, optical bi-stability (OB) and all-optical switching in a system consisting of ultracold 85Rb atoms, trapped in a dark magneto-optical trap (DMOT), coupled to an optical Fabry-Perot cavity. The strong coupling is established by measuring the vacuum Rabi splitting (VRS) of a weak on-axis probe beam. The dependence of VRS on the probe beam power is measured and bi-stability in the cavity transmission is observed. We demonstrate control over the transmission of the probe beam through the atom-cavity system using a free-space off-axis control beam and show that the cavity transmission can be switched on and off in micro-second timescales using micro-Watt control powers. The utility of the system as a tool for sensitive, in-situ and rapid measurements is envisaged.

  4. All-optical sampling and magnification based on XPM-induced focusing

    CERN Document Server

    Nuno, J; Guasoni, M; Finot, C; Fatome, J

    2016-01-01

    We theoretically and experimentally investigate the design of an all-optical noiseless magnification and sampling function free from any active gain medium and associated high-power continuous wave pump source. The proposed technique is based on the co-propagation of an arbitrary shaped signal together with an orthogonally polarized intense fast sinusoidal beating within a normally dispersive optical fiber. Basically, the strong nonlinear phase shift induced by the sinusoidal pump beam on the orthogonal weak signal through cross-phase modulation turns the defocusing regime into localized temporal focusing effects. This periodic focusing is then responsible for the generation of a high-repetition-rate temporal comb upon the incident signal whose amplitude is directly proportional to its initial shape. This internal redistribution of energy leads to a simultaneous sampling and magnification of the signal intensity profile. This process allows us to experimentally demonstrate a 40-GHz sampling operation as well ...

  5. Comparison of Delay-Interferometer and Time- Lens-Based All-Optical OFDM Demultiplexers

    DEFF Research Database (Denmark)

    Lillieholm, Mads; Mulvad, Hans Christian Hansen; Galili, Michael

    2015-01-01

    In this letter, we present the first detailed numerical comparison of two promising all-optical schemes to demultiplex orthogonal frequency-division multiplexing (OFDM) signals. The investigated schemes are the optical discrete Fourier transformation (O-DFT) and the optical spectral magnification...... bandpass filters, is investigated. In the latter scheme, the OFDM spectrum is magnified, allowing for simple optical bandpass filtering of the individual subcarriers with reduced ICI. Ideally, only a single unit consisting of two time lenses is needed, reducing the complexity and potentially the energy...... consumption compared with the type of O-DFT scheme relying on many active gates. The bit-error-rate is estimated down to ~10-6 by Monte Carlo bit-error counting for a 32-subcarrier OFDM input signal, showing that a performance close to the ideal O-DFT is achievable for both the reduced-complexity O...

  6. All-optical generation of DFT-S-OFDM superchannels using periodic sinc pulses.

    Science.gov (United States)

    Lowery, Arthur James; Zhu, Chen; Viterbo, Emanuele; Corcoran, Bill

    2014-11-03

    Discrete-Fourier-transform spread (DFT-S) optical Orthogonal Frequency Division Multiplexed (OFDM) signals offer improved nonlinearity performance in long haul optical communications systems, and can be used to form superchannels. In this paper we propose how DFT-S-OFDM superchannels can be generated and demultiplexed using all-optical techniques, and demonstrate the feasibility using numerical simulations. We also discuss how each wavelength channel is similar to recently proposed Orthogonally Time-Division Multiplexed (OrthTDM) systems using periodic-sinc pulses from, for example, a Nyquist laser. The key difference between OrthTDM and DFT-S-OFDM is the synchronization of the symbol boundaries of every modulation tributary; because of this we show that OrthTDM cannot be formed into superchannels that can be demultiplexed without penalties, but DFT-S-OFDM can be.

  7. Banded all-optical OFDM super-channels with low-bandwidth receivers.

    Science.gov (United States)

    Song, Binhuang; Zhu, Chen; Corcoran, Bill; Zhuang, Leimeng; Lowery, Arthur James

    2016-08-08

    We propose a banded all-optical orthogonal frequency division multiplexing (AO-OFDM) transmission system based on synthesising a number of truncated sinc-shaped subcarriers for each sub-band. This approach enables sub-band by sub-band reception and therefore each receiver's electrical bandwidth can be significantly reduced compared with a conventional AO-OFDM system. As a proof-of-concept experiment, we synthesise 6 × 10-Gbaud subcarriers in both conventional and banded AO-OFDM systems. With a limited receiver electrical bandwidth, the experimental banded AO-OFDM system shows 2-dB optical signal to noise ratio (OSNR) benefit over conventional AO-OFDM at the 7%-overhead forward error correction (FEC) threshold. After transmission over 800-km of single-mode fiber, ≈3-dB improvement in Q-factor can be achieved at the optimal launch power at a cost of increasing the spectral width by 14%.

  8. Comparison of delay-interferometer and time-lens-based all-optical OFDM demultiplexers

    DEFF Research Database (Denmark)

    Lillieholm, Mads; Mulvad, Hans Christian Hansen; Galili, Michael

    2015-01-01

    In this paper we present the first detailed numerical comparison of two promising all-optical schemes to demultiplex orthogonal frequency-division multiplexing (OFDM) signals. The investigated schemes are the optical discrete Fourier transformation (O-DFT) and the optical spectral magnification (SM...... filters, is investigated. In the latter scheme the OFDM spectrum is magnified, allowing for simple optical bandpass filtering of the individual subcarriers with reduced ICI. Ideally only a single unit consisting of two time lenses is needed, reducing the complexity and potentially the energy consumption...... compared to the type of O-DFT scheme relying on many active gates. The bit-error-rate is estimated down to ∼10−6 by Monte Carlo bit-error counting for a 32-subcarrier OFDM input signal, showing that a performance close to the ideal O-DFT is achievable for both the reduced-complexity O-DFT and the SM scheme....

  9. 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.

  10. All-Optical Quantum Random Bit Generation from Intrinsically Binary Phase of Parametric Oscillators

    CERN Document Server

    Marandi, Alireza; Vodopyanov, Konstantin L; Byer, Robert L

    2012-01-01

    True random number generators (RNGs) are desirable for applications ranging from cryptogra- phy to computer simulations. Quantum phenomena prove to be attractive for physical RNGs due to their fundamental randomness and immunity to attack [1]- [5]. Optical parametric down conversion is an essential element in most quantum optical experiments including optical squeezing [9], and generation of entangled photons [10]. In an optical parametric oscillator (OPO), photons generated through spontaneous down conversion of the pump initiate the oscillation in the absence of other inputs [11, 12]. This quantum process is the dominant effect during the oscillation build-up, leading to selection of one of the two possible phase states above threshold in a degenerate OPO [13]. Building on this, we demonstrate a novel all-optical quantum RNG in which the photodetection is not a part of the random process, and no post processing is required for the generated bit sequence. We implement a synchronously pumped twin degenerate O...

  11. Developments of All-optical Half-adder%全光半加器的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙晓寅; 李培丽; 徐荣青

    2009-01-01

    综述了全光半加器的研究进展和现状.阐述了不同结构全光半加器的工作原理、优缺点,并展望了全光半加器未来的发展方向.%It is summarized for current all-optical half-adder.The principles of different kinds of all-optical half-adders are analyzed,and their advantages and disadvantages are also discussed.Finally,the prospects of all-optical half-adder are given.

  12. Experimental and theoretical investigation of electro-optic and all-optical implementations of wavelength converting 2R-regenerators

    DEFF Research Database (Denmark)

    Wolfson, David; Mikkelsen, Benny; Danielsen, Søren Lykke

    1998-01-01

    We investigate and compare the regenerative capability of electro-optic wavelength converters based on electrically controlled external Mach-Zehnder (MZ) modulators and all-optical wavelength converters based on all-optically controlled external MZ modulators. The latter incorporates semiconductor...... optical amplifiers (SOAs) as optically controlled phase shifters. Experiments demonstrate a 5-6 dB noise suppression capability for both the electro-optic and the all-optical implementation of the wavelength-converting regenerators. The performance can be further improved by cascading two converters...

  13. ZnO nanowire-based all-optical switch with Reset-Set flip-flop function

    Science.gov (United States)

    Mu, L. X.; Shi, W. S.; Zhang, T. P.; Zhang, H. Y.; Wang, Y.; She, G. W.; Gao, Y. H.; Wang, P. F.; Chang, J. C.; Lee, S. T.

    2011-04-01

    An all-optical switch with Reset-Set (RS) flip-flop function has been developed by attaching a derivative of spiropyran on the surface of zinc oxide (ZnO) Nanowire. Using UV/visible irradiation and the fluorescence of spiropyran-modified ZnO nanowire as inputs—set/reset and output, RS flip-flop function can be performed on a single ZnO nanowire or a nanowire array. The configuration of the current all-optical switch represents a potential for developing small-sized all-optical devices, which could be further exploited at higher level of integration.

  14. All-optical optoacoustic microscopy system based on probe beam deflection technique

    Science.gov (United States)

    Maswadi, Saher M.; Tsyboulskic, Dmitri; Roth, Caleb C.; Glickman, Randolph D.; Beier, Hope T.; Oraevsky, Alexander A.; Ibey, Bennett L.

    2016-03-01

    It is difficult to achieve sub-micron resolution in backward mode OA microscopy using conventional piezoelectric detectors, because of wavefront distortions caused by components placed in the optical path, between the sample and the objective lens, that are required to separate the acoustic wave from the optical beam. As an alternate approach, an optoacoustic microscope (OAM) was constructed using the probe beam deflection technique (PBDT) to detect laserinduced acoustic signals. The all-optical OAM detects laser-generated pressure waves using a probe beam passing through a coupling medium, such as water, filling the space between the microscope objective lens and sample. The acoustic waves generated in the sample propagate through the coupling medium, causing transient changes in the refractive index that deflect the probe beam. These deflections are measured with a high-speed, balanced photodiode position detector. The deflection amplitude is directly proportional to the magnitude of the acoustic pressure wave, and provides the data required for image reconstruction. The sensitivity of the PBDT detector expressed as noise equivalent pressure was 12 Pa, comparable to that of existing high-performance ultrasound detectors. Because of the unimpeded working distance, a high numerical aperture objective lens, i.e. NA = 1, was employed in the OAM to achieve near diffraction-limited lateral resolution of 0.5 μm at 532nm. The all-optical OAM provides several benefits over current piezoelectric detector-based systems, such as increased lateral and axial resolution, higher sensitivity, robustness, and potentially more compatibility with multimodal instruments.

  15. All-optical histology using two photon laser scanning microscopy and ablation with ultrashort pulses

    Science.gov (United States)

    Tsai, Philbert S.

    This dissertation discusses the use of ultrashort laser pulses to image and manipulate tissue for the purpose of three-dimensional histological reconstruction of extended brain structures. Two photon laser scanning microscopy (TPLSM) and ultrashort pulsed laser ablation are used to provide in situ three-dimensional imaging through thick preparations of fixed tissue. Surface regions of fixed tissue are first imaged using TPLSM. The imaged regions are then removed by ablation with amplified, ultrashort laser pulses, thereby exposing a previously underlying tissue region for imaging. This process of imaging and ablation proceeds iteratively until the desired tissue volume has been processed. First, the principles, design, and construction of a two photon laser scanning microscope are discussed, followed by a discussion of the physical mechanisms of tissue ablation with ultrashort laser pulses. The compatibility of tissue ablation using ultrashort pulses with subsequent histological analysis, particularly with fluorescent microscopy, is evaluated. Tissue ablation with ultrashort laser pulses is found to produce ablated tissue surfaces that are smooth to within a micrometer. Intrinsic fluorescence as well as immunoreactivity are found to be resilient to the ablation process. The all-optical histological technique is demonstrated on brain tissue from rats and mice, including tissue from embryonic mouse as early at E15. The ablation process is shown to preserve both macroscopic and microscopic structures within tissue. To facilitate the all-optical histological analysis of neuronal vasculature and its relative distribution to surrounding neuronal tissue, a fluorescent gel perfusion technique is developed that provides a temperature-stabilized fluorescent label of the neuronal vasculature. The use of immunohistochemistry to label specific cell populations throughout an 800 micrometer-thick tissue section is demonstrated. Additionally, the immersion of fixed tissue in high

  16. All-optical pulse-echo ultrasound probe for intravascular imaging (Conference Presentation)

    Science.gov (United States)

    Colchester, Richard J.; Noimark, Sacha; Mosse, Charles A.; Zhang, Edward Z.; Beard, Paul C.; Parkin, Ivan P.; Papakonstantinou, Ioannis; Desjardins, Adrien E.

    2016-02-01

    High frequency ultrasound probes such as intravascular ultrasound (IVUS) and intracardiac echocardiography (ICE) catheters can be invaluable for guiding minimally invasive medical procedures in cardiology such as coronary stent placement and ablation. With current-generation ultrasound probes, ultrasound is generated and received electrically. The complexities involved with fabricating these electrical probes can result in high costs that limit their clinical applicability. Additionally, it can be challenging to achieve wide transmission bandwidths and adequate wideband reception sensitivity with small piezoelectric elements. Optical methods for transmitting and receiving ultrasound are emerging as alternatives to their electrical counterparts. They offer several distinguishing advantages, including the potential to generate and detect the broadband ultrasound fields (tens of MHz) required for high resolution imaging. In this study, we developed a miniature, side-looking, pulse-echo ultrasound probe for intravascular imaging, with fibre-optic transmission and reception. The axial resolution was better than 70 microns, and the imaging depth in tissue was greater than 1 cm. Ultrasound transmission was performed by photoacoustic excitation of a carbon nanotube/polydimethylsiloxane composite material; ultrasound reception, with a fibre-optic Fabry-Perot cavity. Ex vivo tissue studies, which included healthy swine tissue and diseased human tissue, demonstrated the strong potential of this technique. To our knowledge, this is the first study to achieve an all-optical pulse-echo ultrasound probe for intravascular imaging. The potential for performing all-optical B-mode imaging (2D and 3D) with virtual arrays of transmit/receive elements, and hybrid imaging with pulse-echo ultrasound and photoacoustic sensing are discussed.

  17. OptoDyCE: Automated system for high-throughput all-optical dynamic cardiac electrophysiology

    Science.gov (United States)

    Klimas, Aleksandra; Yu, Jinzhu; Ambrosi, Christina M.; Williams, John C.; Bien, Harold; Entcheva, Emilia

    2016-02-01

    In the last two decades, drugs withdrawals from the market were due to cardiac toxicity, where unintended interactions with ion channels disrupt the heart's normal electrical function. Consequently, all new drugs must undergo preclinical testing for cardiac liability, adding to an already expensive and lengthy process. Recognition that proarrhythmic effects often result from drug action on multiple ion channels demonstrates a need for integrative and comprehensive measurements. Additionally, patient-specific therapies relying on emerging technologies employing stem-cell derived cardiomyocytes (e.g. induced pluripotent stem-cell-derived cardiomyocytes, iPSC-CMs) require better screening methods to become practical. However, a high-throughput, cost-effective approach for cellular cardiac electrophysiology has not been feasible. Optical techniques for manipulation and recording provide a contactless means of dynamic, high-throughput testing of cells and tissues. Here, we consider the requirements for all-optical electrophysiology for drug testing, and we implement and validate OptoDyCE, a fully automated system for all-optical cardiac electrophysiology. We demonstrate the high-throughput capabilities using multicellular samples in 96-well format by combining optogenetic actuation with simultaneous fast high-resolution optical sensing of voltage or intracellular calcium. The system can also be implemented using iPSC-CMs and other cell-types by delivery of optogenetic drivers, or through the modular use of dedicated light-sensitive somatic cells in conjunction with non-modified cells. OptoDyCE provides a truly modular and dynamic screening system, capable of fully-automated acquisition of high-content information integral for improved discovery and development of new drugs and biologics, as well as providing a means of better understanding of electrical disturbances in the heart.

  18. Metamathematics of fuzzy logic

    CERN Document Server

    Hájek, Petr

    1998-01-01

    This book presents a systematic treatment of deductive aspects and structures of fuzzy logic understood as many valued logic sui generis. Some important systems of real-valued propositional and predicate calculus are defined and investigated. The aim is to show that fuzzy logic as a logic of imprecise (vague) propositions does have well-developed formal foundations and that most things usually named `fuzzy inference' can be naturally understood as logical deduction.

  19. Action Type Deontic Logic

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    2014-01-01

    A new deontic logic, Action Type Deontic Logic, is presented. To motivate this logic, a number of benchmark cases are shown, representing inferences a deontic logic should validate. Some of the benchmark cases are singled out for further comments and some formal approaches to deontic reasoning ar...... the benchmarks. Finally, possibilities for further research are indicated. In the appendix, decidability of the satisfiability of formulas is proved via a technique known from monadic First Order Logic....

  20. General Strategy for Broadband Coherent Perfect Absorption and Multi-wavelength All-optical Switching Based on Epsilon-Near-Zero Multilayer Films

    Science.gov (United States)

    Kim, Tae Young; Badsha, Md. Alamgir; Yoon, Junho; Lee, Seon Young; Jun, Young Chul; Hwangbo, Chang Kwon

    2016-03-01

    We propose a general, easy-to-implement scheme for broadband coherent perfect absorption (CPA) using epsilon-near-zero (ENZ) multilayer films. Specifically, we employ indium tin oxide (ITO) as a tunable ENZ material, and theoretically investigate CPA in the near-infrared region. We first derive general CPA conditions using the scattering matrix and the admittance matching methods. Then, by combining these two methods, we extract analytic expressions for all relevant parameters for CPA. Based on this theoretical framework, we proceed to study ENZ CPA in a single layer ITO film and apply it to all-optical switching. Finally, using an ITO multilayer of different ENZ wavelengths, we implement broadband ENZ CPA structures and investigate multi-wavelength all-optical switching in the technologically important telecommunication window. In our design, the admittance matching diagram was employed to graphically extract not only the structural parameters (the film thicknesses and incident angles), but also the input beam parameters (the irradiance ratio and phase difference between two input beams). We find that the multi-wavelength all-optical switching in our broadband ENZ CPA system can be fully controlled by the phase difference between two input beams. The simple but general design principles and analyses in this work can be widely used in various thin-film devices.

  1. Experimental Investigation of Transmission Properties and All-Optical Label Swapping of Orthogonal IM/FSK Labeled Signals

    Institute of Scientific and Technical Information of China (English)

    Pablo; V.; Holm-Nielsen; Christophe; Peucheret; Idelfonso; Tafur; Monroy; Palle; Jeppesen

    2003-01-01

    OpticallylabeledIM/FSKsignalsaretransmittedover50kmofSMFunderdifferentcompensationschemes.All-optical label swapping based on MZ-SOA and EAM is presented. Transmission followed by label swapping shows a 2dB overall power penalty.

  2. Sub-wavelength terahertz beam profiling of a THz source via an all-optical knife-edge technique

    CERN Document Server

    Ho, Sze Phing; Shalaby, Mostafa; Peccianti, Marco; Clerici, Matteo; Pasquazi, Alessia; Ozturk, Yavuz; Ali, Jalil; Morandotti, Roberto

    2015-01-01

    We propose an all-optical Knife Edge characterization technique and we demonstrate its working principle by characterizing the sub-{\\lambda} features of a spatially modulated Terahertz source directly on the nonlinear crystal employed for the Terahertz generation.

  3. Handbook of philosophical logic v.14

    CERN Document Server

    Wick, Manfred; Guenthner, Franz

    2007-01-01

    The fourteenth volume of the Second Edition covers central topics in philosophical logic that have been studied for thousands of years, since Aristotle: Inconsistency, Causality, Conditionals, and Quantifiers. These topics are central in many applications of logic in central disciplines such as computer science, artificial intelligence, linguistics, and philosophy. This book is indispensable to any advanced student or researcher using logic in these areas. The chapters are comprehensive and written by major figures in the field.

  4. Synchronization Algorithm for SDN-controlled All-Optical TDM Switching in a Random Length Ring Network

    DEFF Research Database (Denmark)

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

    2016-01-01

    We propose and demonstrate an algorithm that allows for automatic synchronization of SDN-controlled all-optical TDM switching nodes connected in a ring network. We experimentally show successful WDM-SDM transmission of data bursts between all ring nodes.......We propose and demonstrate an algorithm that allows for automatic synchronization of SDN-controlled all-optical TDM switching nodes connected in a ring network. We experimentally show successful WDM-SDM transmission of data bursts between all ring nodes....

  5. All-optical cryptography of M-QAM formats by using two-dimensional spectrally sliced keys.

    Science.gov (United States)

    Abbade, Marcelo L F; Cvijetic, Milorad; Messani, Carlos A; Alves, Cleiton J; Tenenbaum, Stefan

    2015-05-10

    There has been an increased interest in enhancing the security of optical communications systems and networks. All-optical cryptography methods have been considered as an alternative to electronic data encryption. In this paper we propose and verify the use of a novel all-optical scheme based on cryptographic keys applied on the spectral signal for encryption of the M-QAM modulated data with bit rates of up to 200 gigabits per second.

  6. 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....

  7. Low threshold all-optical crossbar switch on GaAs-GaAlAs channel waveguide arrays

    Science.gov (United States)

    Jannson, Tomasz; Kostrzewski, Andrew

    1994-09-01

    During the Phase 2 project entitled 'Low Threshold All-Optical Crossbar Switch on GaAs - GaAlAs Channel Waveguide Array,' Physical Optics Corporation (POC) developed the basic principles for the fabrication of all-optical crossbar switches. Based on this development. POC fabricated a 2 x 2 GaAs/GaAlAs switch that changes the direction of incident light with minimum insertion loss and nonlinear distortion. This unique technology can be used in both analog and digital networks. The applications of this technology are widespread. Because the all-optical network does not have any speed limitations (RC time constant), POC's approach will be beneficial to SONET networks, phased array radar networks, very high speed oscilloscopes, all-optical networks, IR countermeasure systems, BER equipment, and the fast growing video conferencing network market. The novel all-optical crossbar switch developed in this program will solve interconnect problems. and will be a key component in the widely proposed all-optical 200 Gb/s SONET/ATM networks.

  8. PERFORMANCE OF A NEW DECODING METHOD USED IN OPEN-LOOP ALL-OPTICAL CHAOTIC COMMUNICATION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Liu Huijie; Feng Jiuchao

    2011-01-01

    A new decoding method with decoder is used in open-loop all-optical chaotic communication system under strong injection condition.The performance of the new decoding method is numerically investigated by comparing it with the common decoding method without decoder.For new decoding method,two cases are analyzed,including whether or not the output of the decoder is adjusted by its input to receiver.The results indicate the decoding quality can be improved by adjusting for the new decoding method.Meanwhile,the injection strength of decoder can be restricted in a certain range.The adjusted new decoding method with decoder can achieve better decoding quality than decoding method without decoder when the bit rate of message is under 5 Gb/s.However,a stronger injection for receiver is needed.Moreover,the new decoding method can broaden the range of injection strength acceptable for good decoding quality.Different message encryption techniques are tested,and the result is similar to that of the common decoding method,indicative of the fact that the message encoded by using Chaotic Modulation (CM) can be best recovered by the new decoding method owning to the essence of this encryption technique.

  9. Domain size criterion for the observation of all-optical helicity-dependent switching in magnetic thin films

    Science.gov (United States)

    El Hadri, Mohammed Salah; Hehn, Michel; Pirro, Philipp; Lambert, Charles-Henri; Malinowski, Grégory; Fullerton, Eric E.; Mangin, Stéphane

    2016-08-01

    To understand the necessary condition for the observation of all-optical helicity-dependent switching (AO-HDS) of magnetization in thin films, we investigated ferromagnetic Co/Pt and Co/Ni multilayers as well as ferrimagnetic TbCo alloys as a function of magnetic layer compositions and thicknesses. We show that both ferro- and ferrimagnets with high saturation magnetization show AO-HDS if their magnetic thickness is strongly reduced below a material-dependent threshold thickness. By taking into account the demagnetizing energy and the domain wall energy, we are able to define a criterion to predict whether AO-HDS or thermal demagnetization (TD) will be observed. This criterion for the observation of AO-HDS is that the equilibrium size of magnetic domains forming during the cooling process should be larger than the laser spot size. From these results we anticipate that more magnetic materials are expected to show AO-HDS. However, the effect of the optical pulses' helicity is hidden by the formation of small magnetic domains during the cooling process.

  10. Logic, probability, and human reasoning.

    Science.gov (United States)

    Johnson-Laird, P N; Khemlani, Sangeet S; Goodwin, Geoffrey P

    2015-04-01

    This review addresses the long-standing puzzle of how logic and probability fit together in human reasoning. Many cognitive scientists argue that conventional logic cannot underlie deductions, because it never requires valid conclusions to be withdrawn - not even if they are false; it treats conditional assertions implausibly; and it yields many vapid, although valid, conclusions. A new paradigm of probability logic allows conclusions to be withdrawn and treats conditionals more plausibly, although it does not address the problem of vapidity. The theory of mental models solves all of these problems. It explains how people reason about probabilities and postulates that the machinery for reasoning is itself probabilistic. Recent investigations accordingly suggest a way to integrate probability and deduction.

  11. Structural Logical Relations

    DEFF Research Database (Denmark)

    Schürmann, Carsten; Sarnat, Jeffrey

    2008-01-01

    , such as Twelf, and yet they are often straightforward in proof assistants with stronger meta-logics. In this paper, we propose structural logical relations as a technique for conducting these proofs in systems with limited meta-logical strength by explicitly representing and reasoning about an auxiliary logic......Tait's method (a.k.a. proof by logical relations) is a powerful proof technique frequently used for showing foundational properties of languages based on typed lambda-calculi. Historically, these proofs have been extremely difficult to formalize in proof assistants with weak meta-logics...

  12. All-optical fiber anemometer based on laser heated fiber Bragg gratings.

    Science.gov (United States)

    Gao, Shaorui; Zhang, A Ping; Tam, Hwa-Yaw; Cho, L H; Lu, Chao

    2011-05-23

    A fiber-optic anemometer based on fiber Bragg gratings (FBGs) is presented. A short section of cobalt-doped fiber was utilized to make a fiber-based "hot wire" for wind speed measurement. Fiber Bragg gratings (FBGs) were fabricated in the cobalt-doped fiber using 193 nm laser pulses to serve as localized temperature sensors. A miniature all-optical fiber anemometer is constructed by using two FBGs to determine the dynamic thermal equilibrium between the laser heating and air flow cooling through monitoring the FBGs' central wavelengths. It was demonstrated that the sensitivity of the sensor can be adjusted through the power of pump laser or the coating on the FBG. Experimental results reveal that the proposed FBG-based anemometer exhibits very good performance for wind speed measurement. The resolution of the FBG-based anemometer is about 0.012 m/s for wind speed range between 2.0 m/s and 8.0 m/s.

  13. Manipulation of entanglement sudden death in an all-optical setup

    Science.gov (United States)

    Singh, Ashutosh; Pradyumna, Siva; Rau, A. R. P.; Sinha, Urbasi

    2017-03-01

    The unavoidable and irreversible interaction between an entangled quantum system and its environment causes decoherence of the individual qubits as well as degradation of the entanglement between them. Entanglement sudden death (ESD) is the phenomenon wherein disentanglement happens in finite time even when individual qubits decohere only asymptotically in time due to noise. Prolonging the entanglement is essential for the practical realization of entanglement-based quantum information and computation protocols. For this purpose, the local NOT operation in the computational basis on one or both qubits has been proposed. Here, we formulate an all-optical experimental set-up involving such NOT operations that can hasten, delay, or completely avert ESD, all depending on when it is applied during the process of decoherence. Analytical expressions for these are derived in terms of parameters of the initial state's density matrix, whether for pure or mixed entangled states. After a discussion of the schematics of the experiment, the problem is theoretically analyzed, and simulation results of such manipulations of ESD are presented.

  14. Ultrafast all-optical order-to-chaos transition in silicon photonic crystal chips

    KAUST Repository

    Bruck, Roman

    2016-06-08

    The interaction of light with nanostructured materials provides exciting new opportunities for investigating classical wave analogies of quantum phenomena. A topic of particular interest forms the interplay between wave physics and chaos in systems where a small perturbation can drive the behavior from the classical to chaotic regime. Here, we report an all-optical laser-driven transition from order to chaos in integrated chips on a silicon photonics platform. A square photonic crystal microcavity at telecom wavelengths is tuned from an ordered into a chaotic regime through a perturbation induced by ultrafast laser pulses in the ultraviolet range. The chaotic dynamics of weak probe pulses in the near infrared is characterized for different pump-probe delay times and at various positions in the cavity, with high spatial accuracy. Our experimental analysis, confirmed by numerical modelling based on random matrices, demonstrates that nonlinear optics can be used to control reversibly the chaotic behavior of light in optical resonators. (Figure presented.) . © 2016 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

  15. All-Optical dc Nanotesla Magnetometry Using Silicon Vacancy Fine Structure in Isotopically Purified Silicon Carbide

    Science.gov (United States)

    Simin, D.; Soltamov, V. A.; Poshakinskiy, A. V.; Anisimov, A. N.; Babunts, R. A.; Tolmachev, D. O.; Mokhov, E. N.; Trupke, M.; Tarasenko, S. A.; Sperlich, A.; Baranov, P. G.; Dyakonov, V.; Astakhov, G. V.

    2016-07-01

    We uncover the fine structure of a silicon vacancy in isotopically purified silicon carbide (4H-28SiC) and reveal not yet considered terms in the spin Hamiltonian, originated from the trigonal pyramidal symmetry of this spin-3 /2 color center. These terms give rise to additional spin transitions, which would be otherwise forbidden, and lead to a level anticrossing in an external magnetic field. We observe a sharp variation of the photoluminescence intensity in the vicinity of this level anticrossing, which can be used for a purely all-optical sensing of the magnetic field. We achieve dc magnetic field sensitivity better than 100 nT /√{Hz } within a volume of 3 ×10-7m m3 at room temperature and demonstrate that this contactless method is robust at high temperatures up to at least 500 K. As our approach does not require application of radio-frequency fields, it is scalable to much larger volumes. For an optimized light-trapping waveguide of 3 mm3 , the projection noise limit is below 100 fT /√{Hz } .

  16. Fast all-optical nuclear spin echo technique based on EIT

    Science.gov (United States)

    Walther, Andreas; Nilsson, Adam N.; Li, Qian; Rippe, Lars; Kröll, Stefan

    2016-08-01

    We demonstrate an all-optical Raman spin echo technique, using electromagnetically induced transparency (EIT) to create the pulses required for a spin echo sequence: initialization, pi-rotation, and readout. The first pulse of the sequence induces coherence directly from a mixed state, and the technique is used to measure the nuclear spin coherence of an inhomogeneously broadened ensemble of rare-earth ions (Pr3 +) in a crystal. The rephasing pi-rotation is shown to offer an advantage of combining the rephasing action with the operation of a phase gate, particularly useful in e.g. dynamic decoupling sequences. In contrast to many previous experiments the sequence does not require any preparatory hole burning, which greatly shortens the total duration of the sequence. The effect of the different pulses is characterized by quantum state tomography and compared with simulations. We demonstrate two applications of the technique: compensating the magnetic field across our sample by monitoring T 2 reductions from stray magnetic fields, and measuring coherence times at temperatures up to 11 K, where standard preparation techniques are difficult to implement. We explore the potential of the technique, in particular for systems with much shorter T 2, and other possible applications.

  17. Proposal of all-optical sensor based on nonlinear MMI coupler for multi-purpose usage

    Science.gov (United States)

    Tajaldini, M.; MatJafri, M. Z.

    2015-10-01

    In this study, we propose an all-optical sensor based on consideration the nonlinear effects on modal propagation and output intensity based on ultra-compact nonlinear multimode interference (NLMMI) coupler. The sensor can be tuned to highest sensitivity in the wavelength and refractive index ranges sufficient to detect water- soluble chemical, air pollutions, and heart operation. The results indicate high output sensitivity to input wavelength. This sensitivity guides us to propose a wave sensor both transverse and longitudinal waves such as acoustic and light wave, when an external wave interacts with input waveguide. For instance, this sensor can be implemented by long input that inserted in the land, then any wave could detected from earth. The visible changes of intensity at output facet in various surrounding layer refractive index show the high sensitivity to the refractive index of surrounding layer that is foundation of introducing a sensor. Also, the results show the high distinguished changes on modal expansion and output throat distribution in various refractive indices of surrounding layer.

  18. Continuous all-optical deceleration and single-photon cooling of molecular beams

    Science.gov (United States)

    Jayich, A. M.; Vutha, A. C.; Hummon, M. T.; Porto, J. V.; Campbell, W. C.

    2014-02-01

    Ultracold molecular gases are promising as an avenue to rich many-body physics, quantum chemistry, quantum information, and precision measurements. This richness, which flows from the complex internal structure of molecules, makes the creation of ultracold molecular gases using traditional methods (laser plus evaporative cooling) a challenge, in particular due to the spontaneous decay of molecules into dark states. We propose a way to circumvent this key bottleneck using an all-optical method for decelerating molecules using stimulated absorption and emission with a single ultrafast laser. We further describe single-photon cooling of the decelerating molecules that exploits their high dark state pumping rates, turning the principal obstacle to molecular laser cooling into an advantage. Cooling and deceleration may be applied simultaneously and continuously to load molecules into a trap. We discuss implementation details including multilevel numerical simulations of strontium monohydride. These techniques are applicable to a large number of molecular species and atoms with the only requirement being an electric dipole transition that can be accessed with an ultrafast laser.

  19. Dense all-optical WDM-SCM technology for high-speed computer interconnects

    Science.gov (United States)

    Ih, Charles S.; Tian, Rongsheng; Zhou, H. X.; Xia, Xiang-Gen

    1993-07-01

    We describe a dense and flexible all optical multi-channel communication system for high speed computer interconnects. The system can provide 10 Gb/s for each individual node with a total system capacity to 250 Gb/s using currently available technologies. The system capacity can be scaled to 1 Tb/s using optical amplifiers with a broader bandwidth and higher modulations. The system is based on the multi-beam (heterodyne) modulator (MBM) recently demonstrated in our laboratory and other current technologies in tunable laser arrays and acousto-optical tunable filter (AOTF). Each MBM automatically forms a high frequency microwave sub-carrier multiplexing (SCM) with sub-carrier frequency to tens of GHz. A MBM with sub-carriers at 17 and 21 GHz has already been demonstrated and can be scaled to higher frequencies by using a higher frequency detector. Each SCM group may consist of up to 10 one-Gb/s channels and occupies only 1 nm spectral width. Therefore we can form a conventional WDM with 25 divisions within the bandwidth of commercially available optical amplifiers.

  20. Ultralow bias power all-optical photonic crystal memory realized with systematically tuned L3 nanocavity

    Energy Technology Data Exchange (ETDEWEB)

    Kuramochi, Eiichi, E-mail: kuramochi.eiichi@lab.ntt.co.jp; Nozaki, Kengo; Shinya, Akihiko; Taniyama, Hideaki; Notomi, Masaya [NTT Nanophotonics Center, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); Takeda, Koji; Matsuo, Shinji [NTT Nanophotonics Center, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); NTT Device Technology Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); Sato, Tomonari [NTT Nanophotonics Center, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)

    2015-11-30

    An InP photonic crystal nanocavity with an embedded InGaAsP active region is a unique technology that has realized an all-optical memory with a sub-micro-watt operating power and limitless storage time. In this study, we employed an L3 design with systematic multi-hole tuning, which realized a higher loaded Q factor (>40 000) and a lower mode volume (0.9 μm{sup 3}) than a line-defect-based buried-heterostructure nanocavity (16 000 and 2.2 μm{sup 3}). Excluding the active region realized a record loaded Q factor (210 000) in all for InP-based nanocavities. The minimum bias power for bistable memory operation was reduced to 2.3 ± 0.3 nW, which is about 1/10 of the previous record of 30 nW. This work further established the capability of a bistable nanocavity memory for use in future ultralow-power-consumption on-chip integrated photonics.

  1. Data Transparent and Polarization Insensitive All-Optical Switch based on Fibers with Enhanced Nonlinearity

    Directory of Open Access Journals (Sweden)

    M. Komanec

    2014-09-01

    Full Text Available We have developed a data transparent optical packet switch prototype employing wavelength conversion based on four-wave mixing. The switch is composed of an electro-optical control unit and an all-optical switching segment. To achieve higher switching efficiencies, Ge-doped silica suspended-core and chalcogenide arsenicselenide single-mode fibers were experimentally evaluated and compared to conventional highly-nonlinear fiber. Improved connectorization technology has been developed for Ge-doped suspended-core fiber, where we achieved connection losses of 0.9 dB. For the arsenic-selenide fiber we present a novel solid joint technology, with connection losses of only 0.25 dB, which is the lowest value presented up-to-date. Conversion efficiency of -13.7 dB was obtained for the highly-nonlinear fiber, which is in perfect correlation with previously published results and thus verifies the functionality of the prototype. Conversion efficiency of -16.1 dB was obtained with arsenic-selenide fiber length reduced to five meters within simulations, based on measurement results with a 26 m long component. Employment of such a short arsenic-selenide fiber segment allows significant broadening of the wavelength conversion spectral range due to possible neglection of dispersion.

  2. Polyimide-etalon all-optical ultrasound transducer for high frequency applications

    Science.gov (United States)

    Sheaff, Clay; Ashkenazi, Shai

    2014-03-01

    We have enhanced our design for an all-optical high frequency ultrasound transducer consisting of a UV-absorbing polyimide film integrated into an etalon receiver operating in the NIR range. A dielectric stack having high NIR reflectivity and high UV transmittance was chosen as the first mirror for increased sensitivity and the allowance of polyimide as the etalon medium. A 13 ns, 0.7 μJ optical pulse at 355 nm and a continuous-wave NIR laser were focused onto the structure with a spot diameter of 120 and 35 μm, respectively. In receive mode the etalon had a noise-equivalent pressure of 4.1 kPa over a bandwidth of 5 - 50 MHz (0.61 Pa/√Hz ). The device generated a pressure of 270 kPa at a depth of 200 μm, and the -3 dB bandwidth of the emission extended from 27 to 60 MHz. In transmit/receive mode, the pulse-echo had a center frequency of 35 MHz with a -6 dB bandwidth of 49 MHz (140 %). Lastly, wire targets were imaged by scanning the UV spot to create a synthetic aperture of transmitters centered upon a single receiver.

  3. All-optical optoacoustic microscopy based on probe beam deflection technique

    Directory of Open Access Journals (Sweden)

    Saher M. Maswadi

    2016-09-01

    Full Text Available Optoacoustic (OA microscopy using an all-optical system based on the probe beam deflection technique (PBDT for detection of laser-induced acoustic signals was investigated as an alternative to conventional piezoelectric transducers. PBDT provides a number of advantages for OA microscopy including (i efficient coupling of laser excitation energy to the samples being imaged through the probing laser beam, (ii undistorted coupling of acoustic waves to the detector without the need for separation of the optical and acoustic paths, (iii high sensitivity and (iv ultrawide bandwidth. Because of the unimpeded optical path in PBDT, diffraction-limited lateral resolution can be readily achieved. The sensitivity of the current PBDT sensor of 22 μV/Pa and its noise equivalent pressure (NEP of 11.4 Pa are comparable with these parameters of the optical micro-ring resonator and commercial piezoelectric ultrasonic transducers. Benefits of the present prototype OA microscope were demonstrated by successfully resolving micron-size details in histological sections of cardiac muscle.

  4. Electromagnetically-induced transparency in a diamond spin ensemble enables all-optical electromagnetic field sensing

    CERN Document Server

    Acosta, Victor M; Santori, Charles; Budker, Dmitry; Beausoleil1, Rymond G

    2013-01-01

    We use electromagnetically-induced transparency (EIT) to probe the narrow electron-spin resonance of nitrogen-vacancy centers in diamond. Working with a multi-pass diamond chip at temperatures 6-30 K, the zero-phonon absorption line (637 nm) exhibits an optical depth of 6 and inhomogenous linewidth of ~30 GHz full-width-at-half-maximum (FWHM). Simultaneous optical excitation at two frequencies separated by the ground-state zero-field splitting (2.88 GHz), reveals EIT resonances with a contrast exceeding 6% and FWHM down to 0.4 MHz. The resonances provide an all-optical probe of external electric and magnetic fields with a projected photon-shot-noise-limited sensitivity of 0.2 V/cm/sqrt(Hz) and 0.1 nT/sqrt(Hz), respectively. Operation of a prototype diamond-EIT magnetometer measures a noise floor of less than 1 nT/sqrt(Hz) for frequencies above 10 Hz and Allan deviation of 1.3 +/- 1.1 nT for 100 s intervals. The results demonstrate the potential of diamond-EIT devices for applications ranging from quantum-opti...

  5. Imaging and detection of early stage dental caries with an all-optical photoacoustic microscope

    Science.gov (United States)

    Hughes, D. A.; Sampathkumar, A.; Longbottom, C.; Kirk, K. J.

    2015-01-01

    Tooth decay, at its earliest stages, manifests itself as small, white, subsurface lesions in the enamel. Current methods for detection in the dental clinic are visual and tactile investigations, and bite-wing X-ray radiographs. These techniques suffer from poor sensitivity and specificity at the earliest (and reversible) stages of the disease due to the small size (<100μm) of the lesion. A fine-resolution (600 nm) ultra-broadband (200 MHz) all-optical photoacoustic microscopy system was is used to image the early signs of tooth decay. Ex-vivo tooth samples exhibiting white spot lesions were scanned and were found to generate a larger (one order of magnitude) photoacoustic (PA) signal in the lesion regions compared to healthy enamel. The high contrast in the PA images potentially allows lesions to be imaged and measured at a much earlier stage than current clinical techniques allow. PA images were cross referenced with histology photographs to validate our experimental results. Our PA system provides a noncontact method for early detection of white-spot lesions with a high detection bandwidth that offers advantages over previously demonstrated ultrasound methods. The technique provides the sensing depth of an ultrasound system, but with the spatial resolution of an optical system.

  6. An all-optical Compton source for single-exposure x-ray imaging

    Science.gov (United States)

    Döpp, A.; Guillaume, E.; Thaury, C.; Gautier, J.; Andriyash, I.; Lifschitz, A.; Malka, V.; Rousse, A.; Phuoc, K. Ta

    2016-03-01

    All-optical Compton sources are innovative, compact devices to produce high energy femtosecond x-rays. Here we present results on a single-pulse scheme that uses a plasma mirror to reflect the drive beam of a laser plasma accelerator and to make it collide with the highly-relativistic electrons in its wake. The accelerator is operated in the self-injection regime, producing quasi-monoenergetic electron beams of around 150 MeV peak energy. Scattering with the intense femtosecond laser pulse leads to the emission of a collimated high energy photon beam. Using continuum-attenuation filters we measure significant signal content beyond 100 keV and with simulations we estimate a peak photon energy of around 500 keV. The source divergence is about 13 mrad and the pointing stability is 7 mrad. We demonstrate that the photon yield from the source is sufficiently high to illuminate a centimeter-size sample placed 90 centimeters behind the source, thus obtaining radiographs in a single shot.

  7. Current Developments on Optical Feedback Interferometry as an All-Optical Sensor for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Julien Perchoux

    2016-05-01

    Full Text Available Optical feedback interferometry (OFI sensors are experiencing a consistent increase in their applications to biosensing due to their contactless nature, low cost and compactness, features that fit very well with current biophotonics research and market trends. The present paper is a review of the work in progress at UPC-CD6 and LAAS-CNRS related to the application of OFI to different aspects of biosensing, both in vivo and ex vivo. This work is intended to present the variety of opportunities and potential applications related to OFI that are available in the field. The activities presented are divided into two main sensing strategies: The measurement of optical path changes and the monitoring of flows, which correspond to sensing strategies linked to the reconstruction of changes of amplitude from the interferometric signal, and to classical Doppler frequency measurements, respectively. For optical path change measurements, measurements of transient pulses, usual in biosensing, together with the measurement of large displacements applied to designing palliative care instrumentation for Parkinson disease are discussed. Regarding the Doppler-based approach, progress in flow-related signal processing and applications in real-time monitoring of non-steady flows, human blood flow monitoring and OFI pressure myograph sensing will be presented. In all cases, experimental setups are discussed and results presented, showing the versatility of the technique. The described applications show the wide capabilities in biosensing of the OFI sensor, showing it as an enabler of low-cost, all-optical, high accuracy biomedical applications.

  8. A Survey of Paraconsistent Logics

    CERN Document Server

    Middelburg, C A

    2011-01-01

    A survey of paraconsistent logics that are prominent representatives of the different approaches that have been followed to develop paraconsistent logics is provided. The paraconsistent logics that will be discussed are an enrichment of Priest's logic LP, the logic RM3 from the school of relevance logic, da Costa's logics Cn, Jaskowski's logic D2, and Subrahmanian's logics Ptau. A deontic logic based on the first of these logics will be discussed as well. Moreover, some proposed adaptations of the AGM theory of belief revision to paraconsistent logics will be mentioned.

  9. A modal nonmonotonic logic

    Institute of Scientific and Technical Information of China (English)

    林作铨

    1996-01-01

    A modal nonmonotonic logic is presented based on an experiential modal semantics on typicality and exception.The syntactic and semantics of modal nonmonotonic logic are provided,and the completeness theorem and the theorems relating it to major nonmonotonic logics are proved.It directly formalizes the intuition of nonmonotonic reasoning.Among other things,it provides us a first-order extension of default logic and autoepistemic logic,and simultaneously has the capability of circumscription to infer universal statement.It has important applications in logic programming and deductive data base.As a result,it provides a uniform basis for various nonmonotonic logics,from which the correspondent relationship among major nonmonotonic logics can coincide.

  10. Many-valued logics

    CERN Document Server

    Bolc, Leonard

    1992-01-01

    Many-valued logics were developed as an attempt to handle philosophical doubts about the "law of excluded middle" in classical logic. The first many-valued formal systems were developed by J. Lukasiewicz in Poland and E.Post in the U.S.A. in the 1920s, and since then the field has expanded dramatically as the applicability of the systems to other philosophical and semantic problems was recognized. Intuitionisticlogic, for example, arose from deep problems in the foundations of mathematics. Fuzzy logics, approximation logics, and probability logics all address questions that classical logic alone cannot answer. All these interpretations of many-valued calculi motivate specific formal systems thatallow detailed mathematical treatment. In this volume, the authors are concerned with finite-valued logics, and especially with three-valued logical calculi. Matrix constructions, axiomatizations of propositional and predicate calculi, syntax, semantic structures, and methodology are discussed. Separate chapters deal w...

  11. Institutional Logics in Action

    DEFF Research Database (Denmark)

    Lounsbury, Michael; Boxenbaum, Eva

    2013-01-01

    This double volume presents state-of-the-art research and thinking on the dynamics of actors and institutional logics. In the introduction, we briefly sketch the roots and branches of institutional logics scholarship before turning to the new buds of research on the topic of how actors engage ins...... prolific stream of research on institutional logics by deepening our insight into the active use of institutional logics in organizational action and interaction, including the institutional effects of such (inter)actions....

  12. Propositional Team Logics

    OpenAIRE

    Yang, Fan; Väänänen, Jouko

    2016-01-01

    We consider team semantics for propositional logic, continuing our previous work (Yang & V\\"a\\"an\\"anen 2016). In team semantics the truth of a propositional formula is considered in a set of valuations, called a team, rather than in an individual valuation. This offers the possibility to give meaning to concepts such as dependence, independence and inclusion. We define an expressively maximal propositional team logic, called full propositional team logic. This requires going beyond the logic...

  13. Multimodal photoacoustic and optical coherence tomography scanner using an all optical detection scheme for 3D morphological skin imaging.

    Science.gov (United States)

    Zhang, Edward Z; Povazay, Boris; Laufer, Jan; Alex, Aneesh; Hofer, Bernd; Pedley, Barbara; Glittenberg, Carl; Treeby, Bradley; Cox, Ben; Beard, Paul; Drexler, Wolfgang

    2011-08-01

    A noninvasive, multimodal photoacoustic and optical coherence tomography (PAT/OCT) scanner for three-dimensional in vivo (3D) skin imaging is described. The system employs an integrated, all optical detection scheme for both modalities in backward mode utilizing a shared 2D optical scanner with a field-of-view of ~13 × 13 mm(2). The photoacoustic waves were detected using a Fabry Perot polymer film ultrasound sensor placed on the surface of the skin. The sensor is transparent in the spectral range 590-1200 nm. This permits the photoacoustic excitation beam (670-680 nm) and the OCT probe beam (1050 nm) to be transmitted through the sensor head and into the underlying tissue thus providing a backward mode imaging configuration. The respective OCT and PAT axial resolutions were 8 and 20 µm and the lateral resolutions were 18 and 50-100 µm. The system provides greater penetration depth than previous combined PA/OCT devices due to the longer wavelength of the OCT beam (1050 nm rather than 829-870 nm) and by operating in the tomographic rather than the optical resolution mode of photoacoustic imaging. Three-dimensional in vivo images of the vasculature and the surrounding tissue micro-morphology in murine and human skin were acquired. These studies demonstrated the complementary contrast and tissue information provided by each modality for high-resolution 3D imaging of vascular structures to depths of up to 5 mm. Potential applications include characterizing skin conditions such as tumors, vascular lesions, soft tissue damage such as burns and wounds, inflammatory conditions such as dermatitis and other superficial tissue abnormalities.

  14. Applications of all optical signal processing for advanced optical modulation formats

    Science.gov (United States)

    Nuccio, Scott R.

    signal processing may play a role in the future development of more efficient optical transmission systems. The hope is that performing signal processing in the optical domain may reduce optical-to-electronic conversion inefficiencies, eliminate bottlenecks and take advantage of the ultrahigh bandwidth inherent in optics. While 40 to 50 Gbit/s electronic components are the peak of commercial technology and 100 Gbit/s capable RF components are still in their infancy, optical signal processing of these high-speed data signals may provide a potential solution. Furthermore, any optical processing system or sub-system must be capable of handling the wide array of data formats and data rates that networks may employ. It is also worth noting that future networks may use a combination of data-rates and formats while it has been estimated that "we may start seeing the first commercial use of Terabit Ethernets by 2015". -Robert Metcalfe. To this end, the work presented in this Ph.D. dissertation is aimed at addressing the issue of optical processing for advanced optical modulation formats. All optical multiplexing and demultiplexing of Pol-MUX and phase and QAM encoded signals at the 100 Gbit/s Ethernet standard is addressed. The creation and development of an extremely large continuously tunable all-optical delay capable of handling a variety of modulation formats and data rates is presented. As optical delays are viewed as a critical element to achieve efficient and reconfigurable signal processing, the presented delay line is also utilized to enable a tunable packet buffer capable of handling data packets of varying rate, varying size, and multiple modulation formats.

  15. Silicon Photonics: All-Optical Devices for Linear and Nonlinear Applications

    Science.gov (United States)

    Driscoll, Jeffrey B.

    are shown to contribute no time-averaged momentum. Furthermore, the vectoral modal components, in conjunction with the tensoral nature of the third-order susceptibility of Si, lead to nonlinear properties which are dependent on waveguide orientation with respect to the Si parent crystal and the construction of the modal electric field components. This consideration is used to maximize effective nonlinearity and realize nonlinear Kerr gratings along specific waveguide trajectories. Tight optical confinement leads to a natural enhancement of the intrinsically large effective nonlinearty of Si waveguides, and in fact, the effective nonlinearty can be made to be almost 106 times greater in Si waveguides than that of standard single-mode fiber. Such a large nonlinearity motivates chip-scale all-optical signal processing techniques. Wavelength conversion by both four-wave-mixing (FWM) and cross-phase-modulation (XPM) will be discussed, including a technique that allows for enhanced broadband discrete FWM over arbitrary spectral spans by modulating both the linear and nonlinear waveguide properties through periodic changes in waveguide geometry. This quasi-phase-matching approach has very real applications towards connecting mature telecom sources detectors and components to other spectral regimes, including the mid-IR. Other signal processing techniques such as all-optical modulation format conversion via XPM will also be discussed. This thesis will conclude by looking at ways to extend the bandwidth capacity of Si waveguide interconnects on chip. As the number of processing cores continues to scale as a means for computational performance gains, on-chip link capacity will become an increasingly important issue. Metallic traces have severe limitations and are envisioned to eventually bow to integrated photonic links. The aggregate bandwidth supported by a single waveguide link will therefore become a crucial consideration as integrated photonics approaches the CPU. One way

  16. Efficient Traffic Engineering Strategies for Optimizing Network Throughput in WDM All-Optical Networks

    Directory of Open Access Journals (Sweden)

    Mohamed Koubàa

    2015-05-01

    Full Text Available In this paper we investigate traffic-engineering issues in Wavelength Division Multiplexing (WDM all-optical networks. In such networks, the wavelength continuity constraint along with the wavelength clash constraint, lead to poor network performances when dealing with the lightpath provisioning problem. The impact of these constraints is especially severe when traffic demands are unpredictable and characterized by random arrivals and departures. In order to alleviate the impact of these constraints, we propose to employ intentional/active rerouting. Active lightpath rerouting is to intentionally reroute already established lightpaths, during their life period, so as to achieve a better blocking performance. We here assume that due to the large geographic area an optical WDM network can cover, upgrading such a network to support the huge demand for network bandwidth can be costly. Thereby, it is extremely important for network operators to apply traffic-engineering strategies to cost-effectively optimize network throughput. Two new routing and wavelength assignment (RWA algorithms applying intentional rerouting are proposed. Both algorithms dynamically reroute some already established lightpaths from longer paths to vacant shorter ones so as to reduce the network resources consumption and hence improve the network throughput. The first algorithm, namely, Timer-Based Active Lightpath Rerouting (TB-ALR initiates the rerouting procedure every time a timer expires. The second algorithm, namely, Sequential Routing with Active Lightpath Rerouting (SeqRwALR initiates the rerouting procedure when a connection leaves and its lightpaths are released. To the best of our knowledge, our global approach has not already been investigated in the literature. Simulation results show that the proposed active rerouting algorithms yield much lower connection rejection ratios than rerouting algorithms previously presented in the literature while rerouting a small

  17. Adaptive Light Modulation for Improved Resolution and Efficiency in All-Optical Pulse-Echo Ultrasound.

    Science.gov (United States)

    Alles, Erwin J; Colchester, Richard J; Desjardins, Adrien E

    2016-01-01

    In biomedical all-optical pulse-echo ultrasound systems, ultrasound is generated with the photoacoustic effect by illuminating an optically absorbing structure with a temporally modulated light source. Nanosecond range laser pulses are typically used, which can yield bandwidths exceeding 100 MHz. However, acoustical attenuation within tissue or nonuniformities in the detector or source power spectra result in energy loss at the affected frequencies and in a reduced overall system efficiency. In this work, a laser diode is used to generate linear and nonlinear chirp optical modulations that are extended to microsecond time scales, with bandwidths constrained to the system sensitivity. Compared to those obtained using a 2-ns pulsed laser, pulse-echo images of a phantom obtained using linear chirp excitation exhibit similar axial resolution (99 versus 92 μm, respectively) and signal-to-noise ratios (SNRs) (10.3 versus 9.6 dB). In addition, the axial point spread function (PSF) exhibits lower sidelobe levels in the case of chirp modulation. Using nonlinear (time-stretched) chirp excitations, where the nonlinearity is computed from measurements of the spectral sensitivity of the system, the power spectrum of the imaging system was flattened and its bandwidth broadened. Consequently, the PSF has a narrower axial extent and still lower sidelobe levels. Pulse-echo images acquired with time-stretched chirps as optical modulation have higher axial resolution (64 μm) than those obtained with linear chirps, at the expense of a lower SNR (6.8 dB). Using a linear or time-stretched chirp, the conversion efficiency from optical power to acoustical pressure improved by a factor of 70 or 61, respectively, compared to that obtained with pulsed excitation.

  18. All-optical radiation reaction in head-on laser electron interaction

    Science.gov (United States)

    Vranic, Marija; Grismayer, Thomas; Martins, Joana L.; Fonseca, Ricardo A.; Silva, Luis O.

    2016-10-01

    Radiation reaction (RR) accounts for the slowdown of a charged particle that occurs when a significant fraction of its kinetic energy is emitted as radiation. Here we show that this effect could be measured in an all-optical setup using a laser wakefield accelerated electron beam colliding with an intense laser pulse. We employ full-scale 3D PIC simulations to show that one can enter a radiation reaction dominated regime with a GeV electron beam and a 30 fs laser of I = 1021W/cm2. The electrons can lose up to 40% of their initial energy, which can be used as an experimental signature in the spectra. Our results indicate that modern laser facilities provide an exciting opportunity to explore classical RR and the near-future laser facilities can be employed to study the RR beyond classical description. By using higher laser intensities (1022-1023W/cm2) , quantum effects such as Compton scattering and Breit-Wheeler pair production become relevant. We have included these quantum effects in our PIC code OSIRIS through a Monte Carlo module, and performed a detailed numerical study of the transition from classical to quantum RR dominated regime. We identified the distinct features in the electron distribution function that could serve as signatures of quantum radiation reaction, and showed that large-scale infrastructures (e.g. NIF and ELI and next generation of PW-class lasers (e. g. CoReLS, Bella-i, Texas Petawatt, Apollon 10 PW) could be employed to test the physics in these extreme scenarios.

  19. A logical model of HCP

    Directory of Open Access Journals (Sweden)

    Anatoly D. Plotnikov

    2001-01-01

    Full Text Available For an arbitrary undirected graph G, we are designing a logical model for the Hamiltonian Cycle Problem (HCP, using tools of Boolean algebra only. The obtained model is a logic formulation of the conditions for the existence of the Hamiltonian cycle, and uses m Boolean variables, where m is the number of the edges of a graph. This Boolean expression is true if and only if an initial graph is Hamiltonian. In general, the obtained Boolean expression may have an exponential length (the number of Boolean literals and may be used for construction of the solution algorithm.

  20. The semantics of fuzzy logic

    Science.gov (United States)

    Ruspini, Enrique H.

    1991-01-01

    Summarized here are the results of recent research on the conceptual foundations of fuzzy logic. The focus is primarily on the principle characteristics of a model that quantifies resemblance between possible worlds by means of a similarity function that assigns a number between 0 and 1 to every pair of possible worlds. Introduction of such a function permits one to interpret the major constructs and methods of fuzzy logic: conditional and unconditional possibility and necessity distributions and the generalized modus ponens of Zadeh on the basis of related metric relationships between subsets of possible worlds.

  1. Regular database update logics

    NARCIS (Netherlands)

    Spruit, Paul; Wieringa, Roel; Meyer, John-Jules

    2001-01-01

    We study regular first-order update logic (FUL), which is a variant of regular dynamic logic in which updates to function symbols as well as to predicate symbols are possible. We fi1rst study FUL without making assumptions about atomic updates. Second, we look at relational algebra update logic (RAU

  2. Modalities in medieval logic

    NARCIS (Netherlands)

    Uckelman, S.L.

    2009-01-01

    This dissertation is an exercise in conceptual archeology. Using the tools of contemporary logic we analyse texts in medieval logic and reconstruct their logical theories by creating a formal framework which models them. Our focus is medieval texts which deal with various modalities: the writings on

  3. Tutorial On Fuzzy Logic

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1998-01-01

    A logic based on the two truth values True and False is sometimes inadequate when describing human reasoning. Fuzzy logic uses the whole interval between 0 (False) and 1 (True) to describe human reasoning. As a result, fuzzy logic is being applied in rule based automatic controllers, and this paper...

  4. What are Institutional Logics

    DEFF Research Database (Denmark)

    Berg Johansen, Christina; Waldorff, Susanne Boch

    This study presents new insights into the explanatory power of the institutional logics perspective. With outset in a discussion of seminal theory texts, we identify two fundamental topics that frame institutional logics: overarching institutional orders guides by institutional logics, as well...

  5. Boolean Operator Fuzzy Logic

    Institute of Scientific and Technical Information of China (English)

    刘叙华; 邓安生

    1994-01-01

    A new approach of operator fuzzy logic, Boolean operator fuzzy logic (BOFL) based on Boolean algebra, is presented. The resolution principle is also introduced into BOFL. BOFL is a natural generalization of classical logic and can be applied to the qualitative description of fuzzy knowledge.

  6. Abductive Logic Grammars

    DEFF Research Database (Denmark)

    Christiansen, Henning; Dahl, Veronica

    2009-01-01

    By extending logic grammars with constraint logic, we give them the ability to create knowledge bases that represent the meaning of an input string. Semantic information is thus defined through extra-grammatical means, and a sentence's meaning logically follows as a by-product of string rewriting...

  7. Time Lens based Optical Fourier Transformation for All-Optical Signal Processing of Spectrally-Efficient Data

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Lillieholm, Mads;

    2016-01-01

    four-wave mixing (FWM), separated by a dispersive medium, which enables time-to-frequency and frequency-to-time conversions simultaneously, thus performing an exchange between the temporal and spectral profiles of the input signal. Using the proposed complete OFT, several advanced all-optical signal......We review recent progress in the use of time lens based optical Fourier transformation for advanced all-optical signal processing. A novel time lens based complete optical Fourier transformation (OFT) technique is introduced. This complete OFT is based on two quadratic phase-modulation stages using...... processing schemes for spectrally-efficient systems and networks have been achieved, including all-optical generation, detection and format conversion of spectrally-efficient signals. The spectrally-efficient signals in this paper mainly refer to efficiently multiplexed signals with a high symbol rate per Hz...

  8. Controllable vacuum-induced diffraction of matter-wave superradiance using an all-optical dispersive cavity

    Science.gov (United States)

    Su, Shih-Wei; Lu, Zhen-Kai; Gou, Shih-Chuan; Liao, Wen-Te

    2016-10-01

    Cavity quantum electrodynamics (CQED) has played a central role in demonstrating the fundamental principles of the quantum world, and in particular those of atom-light interactions. Developing fast, dynamical and non-mechanical control over a CQED system is particularly desirable for controlling atomic dynamics and building future quantum networks at high speed. However conventional mirrors do not allow for such flexible and fast controls over their coupling to intracavity atoms mediated by photons. Here we theoretically investigate a novel all-optical CQED system composed of a binary Bose-Einstein condensate (BEC) sandwiched by two atomic ensembles. The highly tunable atomic dispersion of the CQED system enables the medium to act as a versatile, all-optically controlled atomic mirror that can be employed to manipulate the vacuum-induced diffraction of matter-wave superradiance. Our study illustrates a innovative all-optical element of atomtroics and sheds new light on controlling light-matter interactions.

  9. Study of the Performance of an All-Optical Half-Adder Based on Three-Core Non-Linear Directional Fiber Coupler Under Delayed and Instantaneous Non-Linear Kerr Responses

    Science.gov (United States)

    Menezes, J. W. M.; Fraga, W. B.; Lima, F. T.; Guimarães, G. F.; Ferreira, A. C.; Lyra, M. L.; Sombra, A. S. B.

    2011-06-01

    Recently, much attention has been given to the influence of the relaxation process of the non-linear response, because the usual assumption of instantaneous non-linear response fails for ultra-short pulses, and additional contributions coming from non-linear dispersion and delayed non-linearity have to be taken into account. This article presents a numerical analysis of the symmetric planar and asymmetric planar three-core non-linear directional fiber couplers operating with a soliton pulse, where effects of both delayed and instantaneous non-linear Kerr responses are analyzed for implementation of an all-optical half-adder. To implement this all-optical half-adder, eight configurations were analyzed for the non-linear directional fiber coupler, with two symmetric and six asymmetric configurations. The half-adder is the key building block for many digital processing functions, such as shift register, binary counter, and serial parallel data converters. The optical coupler is an important component for applications in optical-fiber telecommunication systems and all integrated optical circuit because of its very high switching speeds. In this numerical simulation, the symmetric/asymmetric planar presents a structure with three cores in a parallel equidistant arrangement, three logical inputs, and two output energy. To prove the effectiveness of the theoretical model for generation of the all-optical half-adder, the best phase to be applied to the control pulse was sought, and a study was done of the extinction ratio level as a function of the Δ > parameter, the normalized time duration, and the Sum and Carry outputs of the (symmetric planar/asymmetric planar) non-linear directional fiber coupler. In this article, the interest is in transmission characteristics, extinction ratio level, normalized time duration, and pulse evolution along the non-linear directional fiber coupler. To compare the performance of the all-optical half-adders, the figure of merit of the

  10. All-Optical 40 Gbit/s Regenerative Wavelength Conversion Based on Cross-Phase Modulation in a Silicon Nanowire

    DEFF Research Database (Denmark)

    Jensen, Asger Sellerup; Hu, Hao; Ji, Hua

    2013-01-01

    We successfully demonstrate all-optical regeneration of a 40 Gbit/s signal based on cross-phase modulation in a silicon nanowire. Bit-error-rate measurements show an average of 1.7dB improvement in receiver sensitivity after the regeneration.......We successfully demonstrate all-optical regeneration of a 40 Gbit/s signal based on cross-phase modulation in a silicon nanowire. Bit-error-rate measurements show an average of 1.7dB improvement in receiver sensitivity after the regeneration....

  11. Ultracompact 160 Gbaud all-optical demultiplexing exploiting slow light in an engineered silicon photonic crystal waveguide.

    Science.gov (United States)

    Corcoran, Bill; Pelusi, Mark D; Monat, Christelle; Li, Juntao; O'Faolain, Liam; Krauss, Thomas F; Eggleton, Benjamin J

    2011-05-01

    We demonstrate all-optical demultiplexing of a high-bandwidth, time-division multiplexed 160 Gbit/s signal to 10 Gbit/s channels, exploiting slow light enhanced four-wave mixing in a dispersion engineered, 96 μm long planar photonic crystal waveguide. We report error-free (bit error rate<10⁻⁹) operation of all 16 demultiplexed channels, with a power penalty of 2.2-2.4 dB, highlighting the potential of these structures as a platform for ultracompact all-optical nonlinear processes.

  12. All-Optical Wavelength Conversion of a High-Speed RZ-OOK Signal in a Silicon Nanowire

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Galili, Michael

    2011-01-01

    All-optical wavelength conversion of a 320 Gb/s line-rate RZ-OOK signal is demonstrated based on four-wave mixing in a 3.6 mm long silicon nanowire. Bit error rate measurements validate the performance within FEC limits.......All-optical wavelength conversion of a 320 Gb/s line-rate RZ-OOK signal is demonstrated based on four-wave mixing in a 3.6 mm long silicon nanowire. Bit error rate measurements validate the performance within FEC limits....

  13. Real-time all-optical OFDM transmission system based on time-domain optical fourier transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Kong, Deming; Røge, Kasper Meldgaard

    2014-01-01

    We propose a novel simple all-optical OFDM transmission system based on time-domain OFT using time-lenses. A real-time 160 Gbit/s DPSK OFDM transmission with 16 decorrelated data subcarriers is successfully demonstrated over 100 km.......We propose a novel simple all-optical OFDM transmission system based on time-domain OFT using time-lenses. A real-time 160 Gbit/s DPSK OFDM transmission with 16 decorrelated data subcarriers is successfully demonstrated over 100 km....

  14. Henkin and Hybrid Logic

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Huertas, Antonia; Manzano, Maria;

    2014-01-01

    Leon Henkin was not a modal logician, but there is a branch of modal logic that has been deeply influenced by his work. That branch is hybrid logic, a family of logics that extend orthodox modal logic with special proposition symbols (called nominals) that name worlds. This paper explains why...... Henkin’s techniques are so important in hybrid logic. We do so by proving a completeness result for a hybrid type theory called HTT, probably the strongest hybrid logic that has yet been explored. Our completeness result builds on earlier work with a system called BHTT, or basic hybrid type theory...... is due to the first-order perspective, which lies at the heart of Henin’s best known work and hybrid logic....

  15. All-Optical Micro Motors Based on Moving Gratings in Photosensitive Media

    Science.gov (United States)

    Curley, M.; Sarkisov, S. S.; Fields, A.; Smith, C.; Kukhtarev, N.; Kulishov, M. B.; Adamovsky, Grigory

    2001-01-01

    An all-optical micromotor with a rotor driven by a traveling wave of surface deformation of a stator being in contact with the rotor is being studied. Instead of an ultrasonic wave produced by an electrically driven piezoelectric actuator as in ultrasonic motors, the wave is a result of a photo-induced surface deformation of a photosensitive material produced by an incident radiation. A thin piezoelectric polymer will deform more easily LiNbO3 or metal when irradiated with light. The type of photosensitive material studied are piezoelectric polymers with and without coatings for connecting electrodes. In order to be considered as a possible candidate for micromotors, the material should exhibit surface deformation produced by a laser beam of the order of 10 microns. This is compared to the deformations produced by static holographic gratings studied in photorefractive crystals of LiNbO3 using high vertical resolution surface profilometer Dektak 3 and surface interferometer WYKO. An experimental setup showing the oscillations has been developed. The setup uses a chopped beam from an Argon ion laser to produce the deformation while a probe beam is reflected by the thin film into a fiber which is then detected on an oscilloscope. A ramp voltage signal generator will drive the piezoelectric film in another experiment to determine the resonance of the film. A current is generated when light is incident upon the film and this current can be measured. The reverse process has already been demonstrated in other piezoelectric actuators. Changing voltage, polarity, and frequency of the signal can easily generate vibrations similar to those when light is incident on the film. This can be compared to the effects of laser interaction with light absorbing fluids such as solutions of 2,9,16,23-Tetrakis(phenylthio)-29H, 31 H-phthalocyanine in chlorobenzene in capillary tubes, The possibility of using a liquid with the piezoelectric film would be a novel idea for a micromotor since

  16. All-Optical 2R Regeneration of a 160-Gbit/s RZOOK Serial Data Signal Using a FOPA

    DEFF Research Database (Denmark)

    Wang, Ju; Ji, Hua; Hu, Hao;

    2012-01-01

    All-optical 2R regeneration of a 160-Gbit/s RZ-OOK signal is demonstrated in a fiber optical parametric amplifier using a highly nonlinear fiber with the data as pump. Bit error rate bathtub curves validate the regeneration performance....

  17. Demonstration of an All-Optical 2-to-4 Level Encoder Based on an Optical Parametric Amplifier

    Directory of Open Access Journals (Sweden)

    Yu Liang

    2009-01-01

    Full Text Available We demonstrated a novel technique for all-optical 2-to-4 level amplitude-shift keying (ASK coding based on a fiber optical parametric amplifier. A 20-Gb/s signal is realized by multiplexing two 10-Gb/s data streams.

  18. An ultra-small, low-power, all-optical flip-flop memory on a silicon chip

    DEFF Research Database (Denmark)

    Liu, Liu; Kumar, R.; Huybrechts, K.

    2010-01-01

    Ultra-small, low-power, all-optical switching and memory elements, such as all-optical flip-flops, as well as photonic integrated circuits of many such elements, are in great demand for all-optical signal buffering, switching and processing. Silicon-on-insulator is considered to be a promising...... platform to accommodate such photonic circuits in large-scale configurations. Through heterogeneous integration of InP membranes onto silicon-on-insulator, a single microdisk laser with a diameter of 7.5 mu m, coupled to a silicon-on-insulator wire waveguide, is demonstrated here as an all-optical flip......-flop working in a continuous-wave regime with an electrical power consumption of a few milliwatts, allowing switching in 60 ps with 1.8 fJ optical energy. The total power consumption and the device size are, to the best of our knowledge, the smallest reported to date at telecom wavelengths. This is also...

  19. New all-optical RIN suppressing, image rejection receiver with efficient use of LO- and signal-power

    DEFF Research Database (Denmark)

    Pedersen, Rune Johan Skullerud; Ebskamp, F.

    1993-01-01

    An all-optical method of achieving a heterodyne signal is presented whereby the local oscillator (LO) relative intensity noise (RIN) and the image channel have been suppressed while efficient use of both LO and signal power is made. This is achieved with only one photodetector, compared to four...

  20. A bit-rate flexible and power efficient all-optical demultiplexer realised by monolithically integrated Michelson interferometer

    DEFF Research Database (Denmark)

    Vaa, Michael; Mikkelsen, Benny; Jepsen, Kim Stokholm;

    1996-01-01

    A novel bit-rate flexible and very power efficient all-optical demultiplexer using differential optical control of a monolithically integrated Michelson interferometer with MQW SOAs is demonstrated at 40 to 10 Gbit/s. Gain switched DFB lasers provide ultra stable data and control signals....

  1. Reduction of pattern effects in SOA-based all-optical switches by using cross-gain modulated holding signal

    DEFF Research Database (Denmark)

    Bischoff, Svend; Mørk, Jesper

    2002-01-01

    , and reduces the fluctuations of the total energy injected into the interferometer within a bit-slot. Thus, we demonstrate a technique for reducing pattern effects in SOAs by employing a partially inverted holding beam. The method should be useful for increasing the data rates of all-optical switches....

  2. Performance analysis of an all-optical OFDM system in presence of non-linear phase noise.

    Science.gov (United States)

    Hmood, Jassim K; Harun, Sulaiman W; Emami, Siamak D; Khodaei, Amin; Noordin, Kamarul A; Ahmad, Harith; Shalaby, Hossam M H

    2015-02-23

    The potential for higher spectral efficiency has increased the interest in all-optical orthogonal frequency division multiplexing (OFDM) systems. However, the sensitivity of all-optical OFDM to fiber non-linearity, which causes nonlinear phase noise, is still a major concern. In this paper, an analytical model for estimating the phase noise due to self-phase modulation (SPM), cross-phase modulation (XPM), and four-wave mixing (FWM) in an all-optical OFDM system is presented. The phase noise versus power, distance, and number of subcarriers is evaluated by implementing the mathematical model using Matlab. In order to verify the results, an all-optical OFDM system, that uses coupler-based inverse fast Fourier transform/fast Fourier transform without any nonlinear compensation, is demonstrated by numerical simulation. The system employs 29 subcarriers; each subcarrier is modulated by a 4-QAM or 16-QAM format with a symbol rate of 25 Gsymbol/s. The results indicate that the phase variance due to FWM is dominant over those induced by either SPM or XPM. It is also shown that the minimum phase noise occurs at -3 dBm and -1 dBm for 4-QAM and 16-QAM, respectively. Finally, the error vector magnitude (EVM) versus subcarrier power and symbol rate is quantified using both simulation and the analytical model. It turns out that both EVM results are in good agreement with each other.

  3. High-Capacity Wireless Signal Generation and Demodulation in 75- to 110-GHz Band Employing All-Optical OFDM

    DEFF Research Database (Denmark)

    Zibar, Darko; Sambaraju, Rakesh; Caballero Jambrina, Antonio

    2011-01-01

    We present a radio-frequency (RF) and bit-rate scalable technique for multigigabit wireless signal generation based on all-optical orthogonal frequency-division multiplexing (OFDM) and photonic up-conversion. Coherent detection supported by digital signal processing is used for signal demodulation...

  4. All-Optical flip-flop operation using a SOA and DFB laser diode optical feedback combination

    DEFF Research Database (Denmark)

    D'Oosterlinck, W.; Öhman, Filip; Buron, Jakob Due;

    2007-01-01

    We report on the switching of an all-optical flip-flop consisting of a semiconductor optical amplifier (SOA) and a distributed feedback laser diode (DFB), bidirectionally coupled to each other. Both simulation and experimental results are presented. Switching times as low as 50ps, minimal required...

  5. All-Optical Flip-Flop Based on an SOA/DFB-Laser Diode Optical Feedback Scheme

    DEFF Research Database (Denmark)

    D'Oosterlinck, W.; Buron, Jakob Due; Öhman, Filip;

    2007-01-01

    We report on the dynamic all-optical flip-flop (AOFF) operation of an optical feedback scheme consisting of a semiconductor optical amplifier (SOA) and a distributed feedback laser diode (DFB-LD), bidirectionally coupled to each other. The operation of the AOFF relies on the interplay between...

  6. All-optical flip-flop operation based on asymmetric active-multimode interferometer bi-stable laser diodes

    DEFF Research Database (Denmark)

    Jiang, H.; Chaen, Y.; Hagio, T.;

    2011-01-01

    We demonstrate fast and low energy all optical flip-flop devices based on asymmetric active-multimode interferometer using high-mesa waveguide structure. The implemented devices showed high speed alloptical flip-flop operation with 25ps long pulses. The rising and falling times of the output sign...

  7. Novel scheme for simple label-swapping employing XOR logic in an integrated interferometric wavelength converter

    DEFF Research Database (Denmark)

    Fjelde, Tina; Kloch, Allan; Wolfson, David;

    2001-01-01

    We present a novel scheme for all-optical label swapping that relies on logic exclusive-OR (XOR) in an integrated SOA-based Michelson interferometer. The scheme allows simple, efficient and mechanically stable operation, while relaxing the requirements on packet format and simplifying switch...

  8. Passive linear-optics 640 Gbit/s logic NOT gate

    DEFF Research Database (Denmark)

    Maram, Reza; Kong, Deming; Galili, Michael;

    2015-01-01

    We experimentally demonstrate a 640 Gbit/s all-optical NOT gate for high-speed telecommunication on-off-keying (OOK) data signals. We employ linear optical signal processing based on spectral phase-only (all-pass) optical filtering to perform the target logic NOT operation....

  9. All optical wavelength conversion and parametric amplification in Ti:PPLN channel waveguides for telecommunication applications

    Energy Technology Data Exchange (ETDEWEB)

    Nouroozi, Rahman

    2010-10-19

    Efficient ultra-fast integrated all-optical wavelength converters and parametric amplifiers transparent to the polarization, phase, and modulation-level and -format are investigated. The devices take advantage of the optical nonlinearity of Ti:PPLN waveguides exploiting difference frequency generation (DFG). In a DFG, the signal ({lambda}{sub s}) is mixed with a pump ({lambda}{sub p}) to generate a wavelength shifted idler (1/{lambda}{sub i}=1/{lambda}{sub p}-1/{lambda}{sub s}). Efficient generation of the pump in Ti:PPLN channel guides is investigated using different approaches. In the waveguide resonators, first a resonance of the fundamental wave alone is considered. It is shown that the maximum power enhancement of the fundamental wave, and therefore the maximum second-harmonic generation (SHG) efficiency, can be achieved with low loss matched resonators. By this way, SHG efficiency of {proportional_to}10300%/W (10.3 %/mW) has been achieved in a 65 mm long waveguide resonator. Its operation for cSHG/DFG requires narrowband reflector for fundamental wave only. Thus, the SH (pump) wave resonator is investigated. The SH-wave resonator enhances the intracavity SH power only. Based on this scheme, an improvement of {proportional_to}10 dB for cSHG/DFG based wavelength conversion efficiency has been achieved with 50 mW of coupled fundamental power in a 30 mm long Ti:PPLN. However, operation was limited to relatively small fundamental power levels (<50 mW) due to the onset of photorefractive instabilities destroying the cavity stabilization. The cSHG/DFG efficiency can be considerably improved by using a double-pass configuration in which all the interacting waves were reflected by a broadband dielectric mirror deposited on the one endface of the waveguide. Three different approaches are investigated and up to 9 dB improvement of the wavelength conversion efficiency in comparison with the single-pass configuration is achieved. Polarization-insensitive wavelength

  10. Logic and structure

    CERN Document Server

    Dalen, Dirk

    1983-01-01

    A book which efficiently presents the basics of propositional and predicate logic, van Dalen’s popular textbook contains a complete treatment of elementary classical logic, using Gentzen’s Natural Deduction. Propositional and predicate logic are treated in separate chapters in a leisured but precise way. Chapter Three presents the basic facts of model theory, e.g. compactness, Skolem-Löwenheim, elementary equivalence, non-standard models, quantifier elimination, and Skolem functions. The discussion of classical logic is rounded off with a concise exposition of second-order logic. In view of the growing recognition of constructive methods and principles, one chapter is devoted to intuitionistic logic. Completeness is established for Kripke semantics. A number of specific constructive features, such as apartness and equality, the Gödel translation, the disjunction and existence property have been incorporated. The power and elegance of natural deduction is demonstrated best in the part of proof theory cal...

  11. Modalities in medieval logic

    OpenAIRE

    2009-01-01

    This dissertation is an exercise in conceptual archeology. Using the tools of contemporary logic we analyse texts in medieval logic and reconstruct their logical theories by creating a formal framework which models them. Our focus is medieval texts which deal with various modalities: the writings on alethic modalities by William of Sherwood, Pseudo-Aquinas, and St. Thomas Aquinas in the 13th century, St. Anselm of Canterbury’s writings on facere and debere in the late 11th century; Lambert of...

  12. Logical database design principles

    CERN Document Server

    Garmany, John; Clark, Terry

    2005-01-01

    INTRODUCTION TO LOGICAL DATABASE DESIGNUnderstanding a Database Database Architectures Relational Databases Creating the Database System Development Life Cycle (SDLC)Systems Planning: Assessment and Feasibility System Analysis: RequirementsSystem Analysis: Requirements Checklist Models Tracking and Schedules Design Modeling Functional Decomposition DiagramData Flow Diagrams Data Dictionary Logical Structures and Decision Trees System Design: LogicalSYSTEM DESIGN AND IMPLEMENTATION The ER ApproachEntities and Entity Types Attribute Domains AttributesSet-Valued AttributesWeak Entities Constraint

  13. Embedding Description Logic Programs into Default Logic

    CERN Document Server

    Wang, Yisong; Yuan, Li Yan; Shen, Yi-Dong; Eiter, Thomas

    2011-01-01

    Description logic programs (dl-programs) under the answer set semantics formulated by Eiter {\\em et al.} have been considered as a prominent formalism for integrating rules and ontology knowledge bases. A question of interest has been whether dl-programs can be captured in a general formalism of nonmonotonic logic. In this paper, we study the possibility of embedding dl-programs into default logic. We show that dl-programs under the strong and weak answer set semantics can be embedded in default logic by combining two translations, one of which eliminates the constraint operator from nonmonotonic dl-atoms and the other translates a dl-program into a default theory. For dl-programs without nonmonotonic dl-atoms but with the negation-as-failure operator, our embedding is polynomial, faithful, and modular. In addition, our default logic encoding can be extended in a simple way to capture recently proposed weakly well-supported answer set semantics, for arbitrary dl-programs. These results reinforce the argument ...

  14. A Logic for Choreographies

    DEFF Research Database (Denmark)

    Lopez, Hugo Andres; Carbone, Marco; Hildebrandt, Thomas

    2010-01-01

    We explore logical reasoning for the global calculus, a coordination model based on the notion of choreography, with the aim to provide a methodology for specification and verification of structured communications. Starting with an extension of Hennessy-Milner logic, we present the global logic (GL...... ), a modal logic describing possible interactions among participants in a choreography. We illustrate its use by giving examples of properties on service specifications. Finally, we show that, despite GL is undecidable, there is a significant decidable fragment which we provide with a sound and complete proof...

  15. A Logic for Choreographies

    CERN Document Server

    Carbone, Marco; Hildebrandt, Thomas T; López, Hugo A; 10.4204/EPTCS.69.3

    2011-01-01

    We explore logical reasoning for the global calculus, a coordination model based on the notion of choreography, with the aim to provide a methodology for specification and verification of structured communications. Starting with an extension of Hennessy-Milner logic, we present the global logic (GL), a modal logic describing possible interactions among participants in a choreography. We illustrate its use by giving examples of properties on service specifications. Finally, we show that, despite GL is undecidable, there is a significant decidable fragment which we provide with a sound and complete proof system for checking validity of formulae.

  16. A Logic for Choreographies

    Directory of Open Access Journals (Sweden)

    Marco Carbone

    2011-10-01

    Full Text Available We explore logical reasoning for the global calculus, a coordination model based on the notion of choreography, with the aim to provide a methodology for specification and verification of structured communications. Starting with an extension of Hennessy-Milner logic, we present the global logic (GL, a modal logic describing possible interactions among participants in a choreography. We illustrate its use by giving examples of properties on service specifications. Finally, we show that, despite GL is undecidable, there is a significant decidable fragment which we provide with a sound and complete proof system for checking validity of formulae.

  17. What is mathematical logic?

    CERN Document Server

    Crossley, J N; Brickhill, CJ; Stillwell, JC

    2010-01-01

    Although mathematical logic can be a formidably abstruse topic, even for mathematicians, this concise book presents the subject in a lively and approachable fashion. It deals with the very important ideas in modern mathematical logic without the detailed mathematical work required of those with a professional interest in logic.The book begins with a historical survey of the development of mathematical logic from two parallel streams: formal deduction, which originated with Aristotle, Euclid, and others; and mathematical analysis, which dates back to Archimedes in the same era. The streams beg

  18. Introduction to mathematical logic

    CERN Document Server

    Mendelson, Elliott

    2015-01-01

    The new edition of this classic textbook, Introduction to Mathematical Logic, Sixth Edition explores the principal topics of mathematical logic. It covers propositional logic, first-order logic, first-order number theory, axiomatic set theory, and the theory of computability. The text also discusses the major results of Gödel, Church, Kleene, Rosser, and Turing.The sixth edition incorporates recent work on Gödel's second incompleteness theorem as well as restoring an appendix on consistency proofs for first-order arithmetic. This appendix last appeared in the first edition. It is offered in th

  19. Ferrite logic reliability study

    Science.gov (United States)

    Baer, J. A.; Clark, C. B.

    1973-01-01

    Development and use of digital circuits called all-magnetic logic are reported. In these circuits the magnetic elements and their windings comprise the active circuit devices in the logic portion of a system. The ferrite logic device belongs to the all-magnetic class of logic circuits. The FLO device is novel in that it makes use of a dual or bimaterial ferrite composition in one physical ceramic body. This bimaterial feature, coupled with its potential for relatively high speed operation, makes it attractive for high reliability applications. (Maximum speed of operation approximately 50 kHz.)

  20. Silicon Photonics for All-Optical Processing and High-Bandwidth-Density Interconnects

    Science.gov (United States)

    Ophir, Noam

    The first chapter of the thesis provides motivation for the integration of silicon photonic modules into compute systems and surveys some of the recent developments in the field. The second chapter then proceeds to detail a technical case study of silicon photonic microring-based WDM links' scalability and power efficiency for these chip I/O applications which could be developed in the intermediate future. The analysis, initiated originally for a workshop on optical and electrical board and rack level interconnects, looks into a detailed model of the optical power budget for such a link capturing both single-channel aspects as well as WDM-operation-related considerations which are unique for a microring physical characteristics. The third chapter, while continuing on the theme silicon photonic high bandwidth density links, proceeds to detail the first experimental demonstration and characterization of an on-chip spatial division multiplexing (SDM) scheme based on microrings for the multiplexing and demultiplexing functionalities. In the context of more forward looking optical network-on-chip environments, SDM-enabled WDM photonic interconnects can potentially achieve superior bandwidth densities per waveguide compared to WDM-only photonic interconnects. The microring-based implementation allows dynamic tuning of the multiplexing and demultiplexing characteristic of the system which allows operation on WDM grid as well device tuning to combat intra-channel crosstalk. The characterization focuses on the first reported power penalty measurements for on-chip silicon photonic SDM link showing minimal penalties achievable with 3 spatial modes concurrently operating on a single waveguide with 10-Gb/s data carried by each mode. The fourth, fifth, and sixth chapters shift in topic from the application of silicon photonics to communication links to the evolving use of silicon waveguides for nonlinear all-optical processing. Chapter four primarily introduces and motivates

  1. The logic of ACP

    NARCIS (Netherlands)

    Ponse, A.; Zwaag, M.B. van der

    2002-01-01

    We distinguish two interpretations for the truth value `undefined' in Kleene's three-valued logic. Combining these two interpretations leads to a four-valued propositional logic that characterizes two particular ingredients of process algebra: ``choice' and ``inaction'. We study two different bases

  2. Identifying Logical Necessity

    Science.gov (United States)

    Yopp, David

    2010-01-01

    Understanding logical necessity is an important component of proof and reasoning for teachers of grades K-8. The ability to determine exactly where young students' arguments are faulty offers teachers the chance to give youngsters feedback as they progress toward writing mathematically valid deductive proofs. As defined, logical necessity is the…

  3. Logic of Algorithmic Knowledge

    Directory of Open Access Journals (Sweden)

    Surowik Dariusz

    2015-09-01

    Full Text Available In this paper we consider the construction of a LAK system of temporal-epistemic logic which is used to formally describe algorithmic knowledge. We propose an axiom system of LAK and discuss the basic properties of this logic.

  4. One reason, several logics

    Directory of Open Access Journals (Sweden)

    Evandro Agazzi

    2011-06-01

    Full Text Available Humans have used arguments for defending or refuting statements long before the creation of logic as a specialized discipline. This can be interpreted as the fact that an intuitive notion of "logical consequence" or a psychic disposition to articulate reasoning according to this pattern is present in common sense, and logic simply aims at describing and codifying the features of this spontaneous capacity of human reason. It is well known, however, that several arguments easily accepted by common sense are actually "logical fallacies", and this indicates that logic is not just a descriptive, but also a prescriptive or normative enterprise, in which the notion of logical consequence is defined in a precise way and then certain rules are established in order to maintain the discourse in keeping with this notion. Yet in the justification of the correctness and adequacy of these rules commonsense reasoning must necessarily be used, and in such a way its foundational role is recognized. Moreover, it remains also true that several branches and forms of logic have been elaborated precisely in order to reflect the structural features of correct argument used in different fields of human reasoning and yet insufficiently mirrored by the most familiar logical formalisms.

  5. Inductive Logic and Statistics

    NARCIS (Netherlands)

    Romeijn, J. -W.

    2009-01-01

    This chapter concerns inductive logic in relation to mathematical statistics. I start by introducing a general notion of probabilistic induc- tive inference. Then I introduce Carnapian inductive logic, and I show that it can be related to Bayesian statistical inference via de Finetti's representatio

  6. Why combine logics?

    NARCIS (Netherlands)

    Blackburn, P.; Rijke, M. de

    1995-01-01

    Combining logics has become a rapidly expanding enterprise that is inspired mainly by concerns about modularity and the wish to join together tailored made logical tools into more powerful but still manageable ones. A natural question is whether it offers anything new over and above existing standar

  7. Programmable Logic Controllers.

    Science.gov (United States)

    Insolia, Gerard; Anderson, Kathleen

    This document contains a 40-hour course in programmable logic controllers (PLC), developed for a business-industry technology resource center for firms in eastern Pennsylvania by Northampton Community College. The 10 units of the course cover the following: (1) introduction to programmable logic controllers; (2) DOS primer; (3) prerequisite…

  8. Layered Fixed Point Logic

    DEFF Research Database (Denmark)

    Filipiuk, Piotr; Nielson, Flemming; Nielson, Hanne Riis

    2012-01-01

    We present a logic for the specification of static analysis problems that goes beyond the logics traditionally used. Its most prominent feature is the direct support for both inductive computations of behaviors as well as co-inductive specifications of properties. Two main theoretical contributions...

  9. Logic via Computer Programming.

    Science.gov (United States)

    Wieschenberg, Agnes A.

    This paper proposed the question "How do we teach logical thinking and sophisticated mathematics to unsophisticated college students?" One answer among many is through the writing of computer programs. The writing of computer algorithms is mathematical problem solving and logic in disguise and it may attract students who would otherwise stop…

  10. Concurrent weighted logic

    DEFF Research Database (Denmark)

    Xue, Bingtian; Larsen, Kim Guldstrand; Mardare, Radu Iulian

    2015-01-01

    We introduce Concurrent Weighted Logic (CWL), a multimodal logic for concurrent labeled weighted transition systems (LWSs). The synchronization of LWSs is described using dedicated functions that, in various concurrency paradigms, allow us to encode the compositionality of LWSs. To reflect these...

  11. Anselm's logic of agency

    NARCIS (Netherlands)

    S.L. Uckelman

    2009-01-01

    The origins of treating agency as a modal concept go back at least to the 11th century when Anselm, Archbishop of Canterbury, provided a modal explication of the Latin facere ‘to do’, which can be formalized within the context of modern modal logic and neighborhood semantics. The agentive logic indu

  12. Logic is Metaphysics

    Directory of Open Access Journals (Sweden)

    Daniel Durante Pereira Alves

    2011-04-01

    Full Text Available Analyzing the position of two philosophers whose views are recognizably divergent, W. O. Quine and M. Dummett, we intend to support a striking point of agreement between them: the idea that our logical principles constitute our principles about what there is, and therefore, that logic is metaphysics.

  13. Logic is Metaphysics

    OpenAIRE

    Daniel Durante Pereira Alves

    2011-01-01

    Analyzing the position of two philosophers whose views are recognizably divergent, W. O. Quine and M. Dummett, we intend to support a striking point of agreement between them: the idea that our logical principles constitute our principles about what there is, and therefore, that logic is metaphysics.

  14. Indexical Hybrid Tense Logic

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Jørgensen, Klaus Frovin

    2012-01-01

    In this paper we explore the logic of now, yesterday, today and tomorrow by combining the semantic approach to indexicality pioneered by Hans Kamp [9] and refined by David Kaplan [10] with hybrid tense logic. We first introduce a special now nominal (our @now corresponds to Kamp’s original now...

  15. Asynchronous, all-optical signal processing based on the self-frequency shift of a gigahertz Raman soliton.

    Science.gov (United States)

    Kato, Masao; Fujiura, Kazuo; Kurihara, Takashi

    2005-03-10

    Ultrafast asynchronous all-optical signal processing is experimentally demonstrated. It is based on the intensity-dependent, self-frequency shift of a gigahertz Raman soliton. We demonstrate error-free, asynchronous, all-optical, bit-by-bit, self-signal recognition and demultiplexing from contended optical packets without use of an optical buffer, control pulse, or bit-phase synchronization. Fourfold, contended, 9.95-Gbit/s optical packets are transmitted through a conventional repeater span of 80 km and simultaneously demultiplexed to multiwavelength 9.95-Gbit/s optical packets with 0.5-dB processing sensitivity. Furthermore, we successfully accomplish demultiplexing from overlapping signals in contended optical packets with better than 3-dB recognition sensitivity. We confirm the capability of realizing a 3x cascade operation from bit-error-rate measurements.

  16. Plasmonic nanoantennas as integrated coherent perfect absorbers on SOI waveguides for modulators and all-optical switches

    CERN Document Server

    Bruck, Roman

    2013-01-01

    The performance of plasmonic nanoantenna structures on top of SOI wire waveguides as coherent perfect absorbers for modulators and all-optical switches is explored. The absorption, scattering, reflection and transmission spectra of gold and aluminum nanoantenna-loaded waveguides were calculated by means of 3D finite-difference time-domain simulations for single waves propagating along the waveguide, as well as for standing wave scenarios composed from two counterpropagating waves. The investigated configurations showed losses of roughly 1% and extinction ratios greater than 25 dB for modulator and switching applications, as well as plasmon effects such as strong field enhancement and localization in the nanoantenna region. The proposed plasmonic coherent perfect absorbers can be utilized for ultracompact all-optical switches in coherent networks as well as modulators and can find applications in sensing or in increasing nonlinear effects.

  17. All-Optical Ultra-High-Speed OFDM to Nyquist-WDM Conversion Based on Complete Optical Fourier Transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2016-01-01

    We propose a novel all-optical ultra-high-speed orthogonal frequency-division multiplexing (OFDM) to Nyquist wavelength-division multiplexing (Nyquist-WDM) conversion scheme, achieved by exchanging the temporal and spectral profiles using a complete optical Fourier transformation (OFT). This scheme...... enables high-speed OFDM to Nyquist-WDM conversion without complex optical/electrical/optical conversion. The all-optical OFDM transmitter is based on the generation of OFDM symbols with a low duty cycle by rectangular temporal gating, which in combination with optical time-division multiplexing yields...... a higher symbol-rate OFDM signal. In the receiver, the converted Nyquist-WDM super-channel is WDM demultiplexed into individual Nyquist-WDM channels using a rectangular optical bandpass filter, followed by optical sampling at the intersymbol-interference free point. In the experimental demonstration...

  18. Performance analysis of relay-assisted all-optical FSO networks over strong atmospheric turbulence channels with pointing errors

    KAUST Repository

    Yang, Liang

    2014-12-01

    In this study, we consider a relay-assisted free-space optical communication scheme over strong atmospheric turbulence channels with misalignment-induced pointing errors. The links from the source to the destination are assumed to be all-optical links. Assuming a variable gain relay with amplify-and-forward protocol, the electrical signal at the source is forwarded to the destination with the help of this relay through all-optical links. More specifically, we first present a cumulative density function (CDF) analysis for the end-to-end signal-to-noise ratio. Based on this CDF, the outage probability, bit-error rate, and average capacity of our proposed system are derived. Results show that the system diversity order is related to the minimum value of the channel parameters.

  19. Design and modeling of an all-optical frequency modulated MEMS strain sensor using nanoscale Bragg gratings

    DEFF Research Database (Denmark)

    Reck, Kasper; Almind, Ninia Sejersen; Mar, Mikkel Dysseholm;

    2009-01-01

    We present modeling and design of an all-optical MEMS Bragg grating (half-pitch of 125 nm) strain sensor for single-fiber distributed sensing. Low optical loss and the use of frequency modulation rather than amplitude modulation, makes this sensor better suited for distributed systems than...... mechanical amplification can be obtained if using an angled double beam micrometer scale MEMS structure, compared to conventional fiber Bragg grating sensors. An optimized design and fabrication process is presented....

  20. On the size-dependent magnetism and all-optical magnetization switching of transition-metal silicide nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Glushkov, G. I.; Tuchin, A. V.; Popov, S. V.; Bityutskaya, L. A., E-mail: me144@phys.vsu.ru [Voronezh State University (Russian Federation)

    2015-12-15

    Theoretical investigations of the electronic structure, synthesis, and all-optical magnetization switching of transition-metal silicide nanostructures are reported. The magnetic moment of the nanostructures is studied as a function of the silicide cluster size and configuration. The experimentally demonstrated magnetization switching of nanostructured nickel silicide by circularly polarized light makes it possible to create high-speed storage devices with high density data recording.

  1. Heterogeneous logics of competition

    DEFF Research Database (Denmark)

    Mossin, Christiane

    2015-01-01

    The purpose of the article is to demonstrate that in order to understand competition as a socially organizing phenomenon, we should not examine competition in isolation, but as constellations of heterogeneous logics. More precisely, the article is based on two main theoretical points: (1) Logics...... of competition are only realized as particular forms of social organization by virtue of interplaying with other kinds of logics, like legal logics. (2) Competition logics enjoy a peculiar status in-between constructedness and givenness; although competition depends on laws and mechanisms of socialization, we...... still experience competition as an expression of spontaneous human activities. On the basis of these perspectives, a study of fundamental rights of EU law, springing from the principle of ‘free movement of people’, is conducted. The first part of the empirical analysis seeks to detect the presence...

  2. FUZZY LOGIC IN LEGAL EDUCATION

    Directory of Open Access Journals (Sweden)

    Z. Gonul BALKIR

    2011-04-01

    Full Text Available The necessity of examination of every case within its peculiar conditions in social sciences requires different approaches complying with the spirit and nature of social sciences. Multiple realities require different and various perceptual interpretations. In modern world and social sciences, interpretation of perception of valued and multi-valued have been started to be understood by the principles of fuzziness and fuzzy logic. Having the verbally expressible degrees of truthness such as true, very true, rather true, etc. fuzzy logic provides the opportunity for the interpretation of especially complex and rather vague set of information by flexibility or equivalence of the variables’ of fuzzy limitations. The methods and principles of fuzzy logic can be benefited in examination of the methodological problems of law, especially in the applications of filling the legal loopholes arising from the ambiguities and interpretation problems in order to understand the legal rules in a more comprehensible and applicable way and the efficiency of legal implications. On the other hand, fuzzy logic can be used as a technical legal method in legal education and especially in legal case studies and legal practice applications in order to provide the perception of law as a value and the more comprehensive and more quality perception and interpretation of value of justice, which is the core value of law. In the perception of what happened as it has happened in legal relationships and formations, the understanding of social reality and sociological legal rules with multi valued sense perspective and the their applications in accordance with the fuzzy logic’s methods could create more equivalent and just results. It can be useful for the young lawyers and law students as a facilitating legal method especially in the materialization of the perception and interpretation of multi valued and variables. Using methods and principles of fuzzy logic in legal

  3. Ultralow-power and ultrafast all-optical tunable plasmon-induced transparency in metamaterials at optical communication range.

    Science.gov (United States)

    Zhu, Yu; Hu, Xiaoyong; Fu, Yulan; Yang, Hong; Gong, Qihuang

    2013-01-01

    Actively all-optical tunable plasmon-induced transparency in metamaterials paves the way for achieving ultrahigh-speed quantum information processing chips. Unfortunately, up to now, very small experimental progress has been made for all-optical tunable plasmon-induced transparency in metamaterials in the visible and near-infrared range because of small third-order optical nonlinearity of conventional materials. The achieved operating pump intensity was as high as several GW/cm(2) order. Here, we report an ultralow-power and ultrafast all-optical tunable plasmon-induced transparency in metamaterials coated on polycrystalline indium-tin oxide layer at the optical communication range. Compared with previous reports, the threshold pump intensity is reduced by four orders of magnitude, while an ultrafast response time of picoseconds order is maintained. This work not only offers a way to constructing photonic materials with large nonlinearity and ultrafast response, but also opens up the possibility for realizing quantum solid chips and ultrafast integrated photonic devices based on metamaterials.

  4. A metro-access integrated network with all-optical virtual private network function using DPSK/ASK modulation format

    Science.gov (United States)

    Tian, Yue; Leng, Lufeng; Su, Yikai

    2008-11-01

    All-optical virtual private network (VPN), which offers dedicated optical channels to connect users within a VPN group, is considered a promising approach to efficient internetworking with low latency and enhanced security implemented in the physical layer. On the other hand, time-division multiplexed (TDM) / wavelength-division multiplexed (WDM) network architecture based on a feeder-ring with access-tree topology, is considered a pragmatic migration scenario from current TDM-PONs to future WDM-PONs and a potential convergence scheme for access and metropolitan networks, due to its efficiently shared hardware and bandwidth resources. All-optical VPN internetworking in such a metro-access integrated structure is expected to cover a wider service area and therefore is highly desirable. In this paper, we present a TDM/WDM metro-access integrated network supporting all-optical VPN internetworking among ONUs in different sub- PONs based on orthogonal differential-phase-shift keying (DPSK) / amplitude-shift keying (ASK) modulation format. In each ONU, no laser but a single Mach-Zehnder modulator (MZM) is needed for the upstream and VPN signal generation, which is cost-effective. Experiments and simulations are performed to verify its feasibility as a potential solution to the future access service.

  5. AN IMPROVED DESIGN OF A MULTIPLIER USING REVERSIBLE LOGIC GATES

    Directory of Open Access Journals (Sweden)

    H.R.BHAGYALAKSHMI

    2010-08-01

    Full Text Available Reversible logic gates are very much in demand for the future computing technologies as they are known to produce zero power dissipation under ideal conditions. This paper proposes an improved design of a multiplier using reversible logic gates. Multipliers are very essential for the construction of various computational units of a quantum computer. The quantum cost of a reversible logic circuit can be minimized by reducing the number of reversible logic gates. For this two 4*4 reversible logic gates called a DPG gate and a BVF gate are used.

  6. Discovering Classes of Strongly Equivalent Logic Programs

    OpenAIRE

    Chen, Y.; Lin, F.

    2011-01-01

    In this paper we apply computer-aided theorem discovery technique to discover theorems about strongly equivalent logic programs under the answer set semantics. Our discovered theorems capture new classes of strongly equivalent logic programs that can lead to new program simplification rules that preserve strong equivalence. Specifically, with the help of computers, we discovered exact conditions that capture the strong equivalence between a rule and the empty set, between two rules, between t...

  7. Mathematical logic for computer science

    CERN Document Server

    Zhong Wan Lu

    1998-01-01

    Mathematical logic is essentially related to computer science. This book describes the aspects of mathematical logic that are closely related to each other, including classical logic, constructive logic, and modal logic. This book is intended to attend to both the peculiarities of logical systems and the requirements of computer science.In this edition, the revisions essentially involve rewriting the proofs, increasing the explanations, and adopting new terms and notations.

  8. Dynamic Logic with Trace Semantics

    OpenAIRE

    Beckert, Bernhard; Bruns, Daniel

    2013-01-01

    Dynamic logic is an established instrument for program verification and for reasoning about the semantics of programs and programming languages. In this paper, we define an extension of dynamic logic, called Dynamic Trace Logic (DTL), which combines the expressiveness of program logics such as dynamic logic with that of temporal logic. And we present a sound and relatively complete sequent calculus for proving validity of DTL formulae. Due to its expressiveness, DTL can serve as a basis for p...

  9. Refinement Modal Logic

    CERN Document Server

    Bozzelli, Laura; French, Tim; Hales, James; Pinchinat, Sophie

    2012-01-01

    In this paper we present refinement modal logic. A refinement is like a bisimulation, except that from the three relational requirements only 'atoms' and 'back' need to be satisfied. Our logic contains a new operator 'forall' in additional to the standard modalities 'Box' for each agent. The operator 'forall' acts as a quantifier over the set of all refinements of a given model. We call it the refinement operator. As a variation on a bisimulation quantifier, it can be seen as a refinement quantifier over a variable not occurring in the formula bound by the operator. The logic combines the simplicity of multi-agent modal logic with some powers of monadic second order quantification. We present a sound and complete axiomatization of multiagent refinement modal logic. We also present an extension of the logic to the modal mu-calculus, and an axiomatization for the single-agent version of this logic. Examples and applications are also discussed: to software verification and design (the set of agents can also be s...

  10. Metaphysics of Logical Realism

    Directory of Open Access Journals (Sweden)

    Mohammadreza Abdollahnejad

    2015-08-01

    Full Text Available Despite the often false impression that the analytic philosophy as an anti-metaphysical movement has nothing to do with metaphysics, there can be found good reasons to grant the metaphysical dispositions of analytic philosophers, and thereby, to minimize the anti-metaphysical nature of analytic philosophy in its all phases. Since analytic philosophy is a historical movement the main nature of which developed through several stages, the very kinds of metaphysical dispositions within each one of its various stages can be easily portrayed. In the meantime, logical realism as the early stage of analytic philosophy contains plenty of metaphysical dispositions. Undoubtedly, one cannot say that analytic philosophy in this period was not committed to metaphysical theses about the plurality of entities, the ultimate nature of reality and the logical structure of the world. In this paper, then, after giving a relatively complete explanation of the logical realism, we claimed that although logical realists rejected the traditional speculative metaphysics of their predecessors, they also replaced it by the metaphysics of logic that pursues the metaphysical aims, this time, by logical means. So, we portrayed this kind of metaphysics as Bolzano’s Semantic Platonism, Frege’s and Russell’s Pluralistic Platonism, Russell’s Pluralistic Atomism, and Wittgenstein’s logical atomism.

  11. Arthur Prior and medieval logic

    OpenAIRE

    2012-01-01

    Though Arthur Prior is now best known for his founding of modern temporal logic and hybrid logic, much of his early philosophical career was devoted to history of logic and historical logic. This interest laid the foundations for both of his ground-breaking innovations in the 1950s and 1960s. Because of the important rôle played by Prior’s research in ancient and medieval logic in his development of temporal and hybrid logic, any student of Prior, temporal logic, or hybrid logic should be fam...

  12. All-optical mode conversion via spatially-multimode four-wave mixing

    CERN Document Server

    Danaci, Onur; Glasser, Ryan T

    2016-01-01

    We experimentally demonstrate the conversion of a Gaussian beam to an approximate Bessel-Gauss mode by making use of a non-collinear four-wave mixing process in hot atomic vapor. The presence of a strong, spatially non-Gaussian pump both converts the probe beam into a non-Gaussian mode, and generates a conjugate beam that is in a similar non-Gaussian mode. The resulting probe and conjugate modes are compared to the output of a Gaussian beam incident on an annular aperture that is then spatially filtered according to the phase-matching conditions imposed by the four-wave mixing process. We find that the resulting experimental data agrees well with both numerical simulations, as well as analytical formulae describing the effects of annular apertures on Gaussian modes. These results show that spatially-multimode gain platforms may be used as a new method of mode conversion.

  13. Fundamental mechanism for all-optical helicity-dependent switching of magnetization

    Science.gov (United States)

    Chen, Xiang-Jun

    2017-01-01

    Switching magnetizations with femtosecond circularly polarized lasers may have revolutionary impacts on magnetic data storage and relevant applications. Achievements in ferrimagnetic and ferromagnetic materials of various structures strongly imply a general phenomenon of fundamental atom-laser interaction. Rotating an atom’s wave function with the rotating electric field of a circularly polarized laser, I show the quantum mechanics for the atom is equivalent to that in a static electric field of the same magnitude and a tremendous static magnetic field which interacts with the atom in somewhat different ways. When some conditions are satisfied, transitions of atoms in these two crossed effective fields lead to a highly nonequilibrium state with orbital magnetic moments inclining to the effective magnetic field. The switching finally completes after the pulse duration via relaxation. PMID:28117460

  14. All-optical cooling of Fermi gases via Pauli inhibition of spontaneous emission

    CERN Document Server

    Onofrio, Roberto

    2016-01-01

    A technique is proposed to cool Fermi gases to the regime of quantum degeneracy based on the expected inhibition of spontaneous emission due to the Pauli principle. The reduction of the linewidth for spontaneous emission originates a corresponding reduction of the Doppler temperature, which under specific conditions may give rise to a runaway process through which fermions are progressively cooled. The approach requires a combination of a magneto-optical trap as a cooling system and an optical dipole trap to enhance quantum degeneracy. This results in expected Fermi degeneracy factors $T/T_F$ comparable to the lowest values recently achieved, with potential for a direct implementation in optical lattices. The experimental demonstration of this technique should also indirectly provide a macroscopic manifestation of the Pauli exclusion principle at the atomic physics level.

  15. All-optical cavity-based simulator of noise-assisted transport

    CERN Document Server

    Viciani, Silvia; Bellini, Marco; Caruso, Filippo

    2015-01-01

    Recent theoretical and experimental efforts have shown the remarkable and counter-intuitive role of noise in enhancing the transport efficiency of complex systems. Here, we realize simple, scalable, and controllable optical fiber cavity networks that allow us to simulate the performance of transport networks for different conditions of interference, dephasing and disorder. In particular, we experimentally demonstrate that the transport efficiency reaches a maximum when varying the external dephasing noise, i.e. a bell-like shape behavior that had been predicted only theoretically. These optical platforms are very promising simulators of transport phenomena, and could be used, in particular, to design and test optimal topologies of artificial light-harvesting structures for future solar energy technologies.

  16. Logic and Learning

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Gierasimczuk, Nina; de Jong, Dick

    2014-01-01

    Learning and learnability have been long standing topics of interests within the linguistic, computational, and epistemological accounts of inductive in- ference. Johan van Benthem’s vision of the “dynamic turn” has not only brought renewed life to research agendas in logic as the study...... of information processing, but likewise helped bring logic and learning in close proximity. This proximity relation is examined with respect to learning and belief revision, updating and efficiency, and with respect to how learnability fits in the greater scheme of dynamic epistemic logic and scientific method....

  17. Continuous Markovian Logics

    DEFF Research Database (Denmark)

    Mardare, Radu Iulian; Cardelli, Luca; Larsen, Kim Guldstrand

    2012-01-01

    Continuous Markovian Logic (CML) is a multimodal logic that expresses quantitative and qualitative properties of continuous-time labelled Markov processes with arbitrary (analytic) state-spaces, henceforth called continuous Markov processes (CMPs). The modalities of CML evaluate the rates...... characterizes stochastic bisimilarity and it supports the definition of a quantified extension of the satisfiability relation that measures the "compatibility" between a model and a property. In this context, the metaproperties allows us to prove two robustness theorems for the logic stating that one can...

  18. Logic in elementary mathematics

    CERN Document Server

    Exner, Robert M

    2011-01-01

    This applications-related introductory treatment explores facets of modern symbolic logic useful in the exposition of elementary mathematics. The authors convey the material in a manner accessible to those trained in standard elementary mathematics but lacking any formal background in logic. Topics include the statement calculus, proof and demonstration, abstract mathematical systems, and the restricted predicate calculus. The final chapter draws upon the methods of logical reasoning covered in previous chapters to develop solutions of linear and quadratic equations, definitions of order and

  19. On the suitability of fibre optical parametric amplifiers for use in all-optical agile photonic networks

    Science.gov (United States)

    Gryspolakis, Nikolaos

    B. Next, we introduce modulated channels to the amplifier in order to compare their effect on the Bit Error Rate (BER) performance. We consider the impact on FOPAs when employing different modulation formats, such as RZ, NRZ and RZ-DPSK. Carefully selected modulation formats can improve BER performance and reduce the effects of cross-phase modulation, four wave mixing (FWM) products generation or dispersion (non-linear and linear inter-channel interference). Especially for the case of FOPAs, because of the ultra-fast interaction times of the FWM phenomenon, cross gain modulation can be a great deterrent for using FOPAs. We use RZ-DPSK in order to suppress the WDM signal crosstalk. Only by using RZ-DPSK, we obtain an improved receiver sensitivity of 5 dB when operating at 40 Gb/s. Finally, we investigate ways to mitigate such effects as the ones described above (gain excursions, gain tilt, etc.). We demonstrate that by using a ring configuration with optical feedback for the first time in FOPAs, we can achieve all-optical gain clamping (AOGC), mitigating gain excursions and attaining gain, independent of channel input power for a large range of PCIP. For example, with the use of AOGC, we reduce the add/drop-induced gain excursions from 4 dB to 0.6 dB. Also, by the combined use of AOGC and RZ-DPSK, we mitigate most of the aforementioned hindrances described above.

  20. Advances in temporal logic

    CERN Document Server

    Fisher, Michael; Gabbay, Dov; Gough, Graham

    2000-01-01

    Time is a fascinating subject that has captured mankind's imagination from ancient times to the present. It has been, and continues to be studied across a wide range of disciplines, from the natural sciences to philosophy and logic. More than two decades ago, Pnueli in a seminal work showed the value of temporal logic in the specification and verification of computer programs. Today, a strong, vibrant international research community exists in the broad community of computer science and AI. This volume presents a number of articles from leading researchers containing state-of-the-art results in such areas as pure temporal/modal logic, specification and verification, temporal databases, temporal aspects in AI, tense and aspect in natural language, and temporal theorem proving. Earlier versions of some of the articles were given at the most recent International Conference on Temporal Logic, University of Manchester, UK. Readership: Any student of the area - postgraduate, postdoctoral or even research professor ...

  1. Dialectic operator fuzzy logic

    Institute of Scientific and Technical Information of China (English)

    程晓春; 姜云飞; 刘叙华

    1996-01-01

    Dialectic operator fuzzy logic (DOFL) is presented which is relevant,paraconsistent and nonmonotonic.DOFL can vividly describe the belief revision in the cognitive process and can infer reasonably well while the knowledge is inconsistent,imprecise or incomplete.

  2. Reasoning, logic, and psychology.

    Science.gov (United States)

    Stenning, Keith; van Lambalgen, Michiel

    2011-09-01

    We argue that reasoning has been conceptualized so narrowly in what is known as 'psychology of reasoning' that reasoning's relevance to cognitive science has become well-nigh invisible. Reasoning is identified with determining whether a conclusion follows validly from given premises, where 'valid' is taken to mean 'valid according to classical logic'. We show that there are other ways to conceptualize reasoning, more in line with current logical theorizing, which give it a role in psychological processes ranging from (verbal) discourse comprehension to (nonverbal) planning. En route we show that formal logic, at present marginalized in cognitive science, can be an extremely valuable modeling tool. In particular, there are cases in which probabilistic modeling must fail, whereas logical models do well. WIREs Cogni Sci 2011 2 555-567 DOI: 10.1002/wcs.134 For further resources related to this article, please visit the WIREs website.

  3. Logics for XML

    CERN Document Server

    Geneves, Pierre

    2008-01-01

    This thesis describes the theoretical and practical foundations of a system for the static analysis of XML processing languages. The system relies on a fixpoint temporal logic with converse, derived from the mu-calculus, where models are finite trees. This calculus is expressive enough to capture regular tree types along with multi-directional navigation in trees, while having a single exponential time complexity. Specifically the decidability of the logic is proved in time 2^O(n) where n is the size of the input formula. Major XML concepts are linearly translated into the logic: XPath navigation and node selection semantics, and regular tree languages (which include DTDs and XML Schemas). Based on these embeddings, several problems of major importance in XML applications are reduced to satisfiability of the logic. These problems include XPath containment, emptiness, equivalence, overlap, coverage, in the presence or absence of regular tree type constraints, and the static type-checking of an annotated query....

  4. CONCEPT OF SUSTAINABILITY – A LOGICAL APPROACH

    Directory of Open Access Journals (Sweden)

    EMIL DINGA

    2011-04-01

    Full Text Available The paper aims to achieve a definition of the concept of sustainability and of sustainable system from a logical perspective. In this respect, it introduces and defines (through the sufficiency predicates the concept of logically vivid system and, on this basis, are discussed a logical concept of sustainability, respectively of a sustainable system in general are discussed and built up. Sustainability is considered in light of identity preservation of the systems, as a static anchor, on one hand, and of the concept of automatic stabilizers as a dynamic anchor on the other side. Finally, the two sufficiency conditions for a logically vivid system be sustainable are identified: the presence of hyper-cycles, respectively the absence of positive feed-back.

  5. Technology of optical switch in all optical communication%全光通信中的光开关技术

    Institute of Scientific and Technical Information of China (English)

    李红春; 赵巧霞; 陶晓燕; 王豆豆

    2011-01-01

    Optical switch is the kernel device of all optical switchingCurrently the study on optical switch has become the focus of all optical communication. This paper summarized the principle of optical switch, analyzed the application of optical switch. The traditional mechanical, micro electro-mechanical system (MEMS) and thermo-optic switch were further divided, and their characteristics were pointed out. Then an evaluation system was put forward for optical switch assessment, by comparing the qualitative and quantitative of the four common optical switches,the advatnges and inadequacics of different types of optical switches were pointed out. Finauy,according to the trend of all optical communication, the large-scale array, high speed, transparent and low loss optical switch is the key development of direction.%光开关是实现全光交换的核心器件,光开关的研究已成为全光通信领域研究的焦点.本文首先对光开关的原理进行归纳,总结光开关的应用范围.对传统机械式光开关、微电子机械式光开关、热光开关进行了进一步地划分,分析了它们的结构形式和性能特点.设计了光开关性能评价指标体系,对常见的4种光开关进行了定性与定量对比,指出不同类型光开关的优点和不足之处.最后依据全光通信网的发展趋势,指出大容童、高速、透明、低损耗是光开关的重点发展方向.

  6. Logic for Language Learning

    Institute of Scientific and Technical Information of China (English)

    Simon Mumford takes a more 'logical' view of gramm

    2010-01-01

    @@ Many people enjoy puzzles and solving prob lems,and the use of an element of logic can make grammar exercises more interesting.Exercises such as putting words in order and clozes can be consid ered forms of puzzles,but there are many more op portunities to challenge more logically-minded stu dents.Here are some language puzzles for students and teachers alike.

  7. Logic for physical space

    DEFF Research Database (Denmark)

    Aiello, Marco; Bezhanishvili, Guram; Bloch, Isabelle

    2012-01-01

    Since the early days of physics, space has called for means to represent, experiment, and reason about it. Apart from physicists, the concept of space has intrigued also philosophers, mathematicians and, more recently, computer scientists. This longstanding interest has left us with a plethora......, we do not only consider classical logic, but we indulge ourselves with modal logics. These present themselves naturally by providing simple axiomatizations of different geometries, topologies, space-time causality, and vector spaces....

  8. Introduction to logic design

    CERN Document Server

    Yanushkevich, Svetlana N

    2008-01-01

    Preface Design Process and Technology Theory of logic design Analysis and synthesis Implementation technologies Predictable technologies Contemporary CAD of logic networks Number Systems Positional numbers Counting in a positional number system Basic arithmetic operations in various number systems Binary arithmetic Radix-complement representations Techniques for conversion of numbers in various radices Overflow Residue arithmetic Other binary codes Redundancy and reliability Graphical Data Structures Graphs in discrete devices and systems design Basic definitions T

  9. A Conceptual Space Logic

    DEFF Research Database (Denmark)

    Nilsson, Jørgen Fischer

    1999-01-01

    Conceptual spaces have been proposed as topological or geometric means for establishing conceptual structures and models. This paper, after briey reviewing conceptual spaces, focusses on the relationship between conceptual spaces and logical concept languages with operations for combining concepts...... to form concepts. Speci cally is introduced an algebraic concept logic, for which conceptual spaces are installed as semantic domain as replacement for, or enrichment of, the traditional....

  10. Logic and declarative language

    CERN Document Server

    Downward, M

    2004-01-01

    Logic has acquired a reputation for difficulty, perhaps because many of the approaches adopted have been more suitable for mathematicians than computer scientists. This book shows that the subject is not inherently difficult and that the connections between logic and declarative language are straightforward. Many exercises have been included in the hope that these will lead to a much greater confidence in manual proofs, therefore leading to a greater confidence in automated proofs.

  11. Construct Graph Logic

    OpenAIRE

    Tan, Yong

    2013-01-01

    In this paper, author uses set theory to construct a logic model of abstract figure from binary relation. Based on the uniform quantified structure, author gives two logic system for graph traversal and graph coloring respectively, moreover shows a new method of cutting graph. Around this model, there are six algorithms in this paper including exact graph traversal, Algebra calculation of natural number, graph partition and graph coloring.

  12. Multiple neural representations of elementary logical connectives.

    Science.gov (United States)

    Baggio, Giosuè; Cherubini, Paolo; Pischedda, Doris; Blumenthal, Anna; Haynes, John-Dylan; Reverberi, Carlo

    2016-07-15

    A defining trait of human cognition is the capacity to form compounds out of simple thoughts. This ability relies on the logical connectives AND, OR and IF. Simple propositions, e.g., 'There is a fork' and 'There is a knife', can be combined in alternative ways using logical connectives: e.g., 'There is a fork AND there is a knife', 'There is a fork OR there is a knife', 'IF there is a fork, there is a knife'. How does the brain represent compounds based on different logical connectives, and how are compounds evaluated in relation to new facts? In the present study, participants had to maintain and evaluate conjunctive (AND), disjunctive (OR) or conditional (IF) compounds while undergoing functional MRI. Our results suggest that, during maintenance, the left posterior inferior frontal gyrus (pIFG, BA44, or Broca's area) represents the surface form of compounds. During evaluation, the left pIFG switches to processing the full logical meaning of compounds, and two additional areas are recruited: the left anterior inferior frontal gyrus (aIFG, BA47) and the left intraparietal sulcus (IPS, BA40). The aIFG shows a pattern of activation similar to pIFG, and compatible with processing the full logical meaning of compounds, whereas activations in IPS differ with alternative interpretations of conditionals: logical vs conjunctive. These results uncover the functions of a basic cortical network underlying human compositional thought, and provide a shared neural foundation for the cognitive science of language and reasoning.

  13. All-optical non-demolition measurement of single-hole spin in a quantum-dot molecule

    OpenAIRE

    F. Troiani; Wilson-Rae, I.; Tejedor, C.

    2006-01-01

    We propose an all-optical scheme to perform a non-demolition measurement of a single hole spin localized in a quantum-dot molecule. The latter is embedded in a microcavity and driven by two lasers. This allows to induce Raman transitions which entangle the spin state with the polarization of the emitted photons. We find that the measurement can be completed with high fidelity on a timescale of 100 ps, shorter than the typical T2. Furthermore, we show that the scheme can be used to induce and ...

  14. All-optical multi-channel wavelength conversion of Nyquist 16 QAM signal using a silicon waveguide.

    Science.gov (United States)

    Long, Yun; Liu, Jun; Hu, Xiao; Wang, Andong; Zhou, Linjie; Zou, Kaiheng; Zhu, Yixiao; Zhang, Fan; Wang, Jian

    2015-12-01

    We experimentally demonstrate on-chip all-optical multi-channel wavelength conversion of Nyquist 16 ary quadrature amplitude modulation (16 QAM) signal in a silicon waveguide. The measured optical signal-to-noise ratio (OSNR) penalties of wavelength conversion are ∼2  dB. The observed constellations of converted idlers indicate favorable performance of silicon-waveguide-based multi-channel wavelength conversion. We also experimentally study and compare the phase-conjugated wavelength conversion by degenerate four-wave mixing (FWM) and transparent wavelength conversion by non-degenerate FWM in the silicon waveguide.

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

    Institute of Scientific and Technical Information of China (English)

    ZHUANG You-Yi; ZHANG Yao-Ju

    2009-01-01

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

  16. 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 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...

  17. All-Optical envelope detection and fiber transmission of wireless signals by external injection of a DFB laser

    DEFF Research Database (Denmark)

    Prince, Kamau; Tafur Monroy, Idelfonso

    2008-01-01

    We outline a novel method for all-optical envelope detection of wireless signals by exploiting cross-gain modulation effects in a distributed feedback laser operating with optical injection. We successfully demonstrate envelope detection of a 20-GHz carrier amplitude-shift-keying modulated signal...... at 2.5 Gb/s and its transmission over a 70-km optical fiber link. We present results including bit-error-rate measurements, signal waveforms, and receiver sensitivity penalties associated with envelope detection and fiber transmission....

  18. A low-power all-optical bistable device based on a liquid crystal layer embedded in thin gold films

    Science.gov (United States)

    Takase, Yuki; Tien Thanh, Pham; Fujimura, Ryushi; Kajikawa, Kotaro

    2014-04-01

    An all-optical bistable (AOB) resonator device composed of a 430-nm-thick liquid crystal (LC) layer embedded in two thin gold films (MLM) is reported in this paper. This device allows the use of the incident illumination at normal incidence, whereas the previous AOB devices based on twisted nematic (TN)-LC function only for illumination at oblique incidence. The fastest switching time was measured to be 1.8 ms, which is significantly faster than that of TN-LC. Because the MLM device operates free from electronic circuits, it is promising for two-dimensional optical data processing, random access optical memories, and spatial light modulators.

  19. All-optical wavelength conversion at bit rates above 10 Gb/s using semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Jørgensen, Carsten; Danielsen, Søren Lykke; Stubkjær, Kristian

    1997-01-01

    This work assesses the prospects for high-speed all-optical wavelength conversion using the simple optical interaction with the gain in semiconductor optical amplifiers (SOAs) via the interband carrier recombination. Operation and design guidelines for conversion speeds above 10 Gb/s are described...... and the various tradeoffs are discussed. Experiments at bit rates up to 40 Gb/s are presented for both cross-gain modulation (XGM) and cross-phase modulation (XPM) in SOAs demonstrating the high-speed capability of these techniques...

  20. Free-carrier contribution to all-optical switching in Mie-resonant hydrogenated amorphous silicon nanodisks

    Science.gov (United States)

    Vabishchevich, Polina P.; Shorokhov, Alexander S.; Shcherbakov, Maxim R.; Fedyanin, Andrey A.

    2016-03-01

    Conventionally, all-optical switching devices made out from bulk silicon and other semiconductors are limited by free-carrier relaxation time which spans from picoseconds to microseconds. In this work, we discuss the possibility to suppress the undesired long free-carrier relaxation in subwavelength dielectric nanostructures exhibiting localized magnetic Mie resonances. Numerical calculations show the unsymmetrical modification of the transmittance spectra of the nanodisks due the free carriers photo-injection. Such a spectral dependance allows to control temporal response of the nanostructure by varying the laser pulse spectum.

  1. An all-optical switch of Mach-Zehnder interferometer type using an active fibre ring resonator

    Institute of Scientific and Technical Information of China (English)

    Li Jun-Qing; Alireza Bananej; Li Qiang-Hua; Chen Qiang; Li Chun-Fei

    2004-01-01

    We propose an all-optical switch of the Mach-Zehnder interferometer type using an active nonlinear ring resonatorand analyse the significance of the parameter A, a product of gain and total loss, for performing an ideal 1 by 2switch. We found that in the range of 1 - κ≤ A ≤√/1 - k, the increment of A can compensate the losses insidethe ring, therefore increase the finesse of the ring and enhance the nonlinearity contribution to reduce the switchingpower threshold effectively. We also emphasize the importance of the initial switching point and discuss the feasibilityof utilizing a high-nonlinear fibre in the ring.

  2. Demonstration of all-optical phase noise suppression scheme using optical nonlinearity and conversion/dispersion delay.

    Science.gov (United States)

    Chitgarha, Mohammad Reza; Khaleghi, Salman; Ziyadi, Morteza; Mohajerin-Ariaei, Amirhossein; Almaiman, Ahmed; Daab, Wajih; Rogawski, Devora; Tur, Moshe; Touch, Joseph D; Langrock, Carsten; Fejer, Martin M; Willner, Alan E

    2014-05-15

    We propose and demonstrate an all-optical phase noise reduction scheme that uses optical nonlinear mixing and tunable optical delays to suppress the low-speed phase noise induced by laser linewidth. By utilizing the phase conjugate copy of the original signal and two narrow-linewidth optical pumps, the phase noise induced by laser linewidth can be reduced by a factor of ∼5 for a laser with 500-MHz phase noise bandwidth. The error-vector-magnitude can be improved from ∼30% to ∼14% for the same laser linewidth for 40-Gbit/s quadrature phase shift keying signal.

  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 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. Arthur Prior and medieval logic

    NARCIS (Netherlands)

    Uckelman, S.L.

    2012-01-01

    Though Arthur Prior is now best known for his founding of modern temporal logic and hybrid logic, much of his early philosophical career was devoted to history of logic and historical logic. This interest laid the foundations for both of his ground-breaking innovations in the 1950s and 1960s. Becaus

  5. Relational Parametricity and Separation Logic

    DEFF Research Database (Denmark)

    Birkedal, Lars; Yang, Hongseok

    2008-01-01

    Separation logic is a recent extension of Hoare logic for reasoning about programs with references to shared mutable data structures. In this paper, we provide a new interpretation of the logic for a programming language with higher types. Our interpretation is based on Reynolds's relational...... parametricity, and it provides a formal connection between separation logic and data abstraction. Udgivelsesdato: 2008...

  6. Design of all-optical high-order temporal integrators based on multiple-phase-shifted Bragg gratings.

    Science.gov (United States)

    Asghari, Mohammad H; Azaña, José

    2008-07-21

    In exact analogy with their electronic counterparts, photonic temporal integrators are fundamental building blocks for constructing all-optical circuits for ultrafast information processing and computing. In this work, we introduce a simple and general approach for realizing all-optical arbitrary-order temporal integrators. We demonstrate that the N(th) cumulative time integral of the complex field envelope of an input optical waveform can be obtained by simply propagating this waveform through a single uniform fiber/waveguide Bragg grating (BG) incorporating N pi-phase shifts along its axial profile. We derive here the design specifications of photonic integrators based on multiple-phase-shifted BGs. We show that the phase shifts in the BG structure can be arbitrarily located along the grating length provided that each uniform grating section (sections separated by the phase shifts) is sufficiently long so that its associated peak reflectivity reaches nearly 100%. The resulting designs are demonstrated by numerical simulations assuming all-fiber implementations. Our simulations show that the proposed approach can provide optical operation bandwidths in the tens-of-GHz regime using readily feasible photo-induced fiber BG structures.

  7. All-optical production and trapping of metastable noble gas atoms down to the single atom regime

    CERN Document Server

    Kohler, M; Sahling, P; Sieveke, C; Jerschabek, N; Kalinowski, M B; Becker, C; Sengstock, K

    2014-01-01

    The determination of isotope ratios of noble gas atoms has many applications e.g. in physics, nuclear arms control, and earth sciences. For several applications, the concentration of specific noble gas isotopes (e.g. Kr and Ar) is so low that single atom detection is highly desirable for a precise determination of the concentration. As an important step in this direction, we demonstrate operation of a krypton Atom Trap Trace Analysis (ATTA) setup based on a magneto-optical trap (MOT) for metastable Kr atoms excited by all-optical means. Compared to other state-of-the-art techniques for preparing metastable noble gas atoms, all-optical production is capable of overcoming limitations regarding minimal probe volume and avoiding cross-contamination of the samples. In addition, it allows for a compact and reliable setup. We identify optimal parameters of our experimental setup by employing the most abundant isotope Kr-84, and demonstrate single atom detection within a 3D MOT.

  8. Monitoring burst (M-burst) — A novel framework of failure localization in all-optical mesh networks

    KAUST Repository

    Ali, Mohammed L.

    2011-10-10

    Achieving instantaneous and precise failure localization in all-optical wavelength division multiplexing (WDM) networks has been an attractive feature of network fault management systems, and is particularly important when failure-dependent protection is employed. The paper introduces a novel framework of real-time failure localization in all-optical WDM mesh networks, called monitoring-burst (m-burst), which aims to initiate a graceful compromise between consumed monitoring resources and monitoring delay. Different from any previously reported solution, the proposed m-burst framework has a single monitoring node (MN) which launches optical bursts along a set of pre-defined close-loop routes, called monitoring cycles (m-cycles), to probe the links along the m-cycles. Bursts along different m-cycles are kept non-overlapping through any link of the network. By identifying the lost bursts due to single link failure events only, the MN can unambiguously localize the failed link in at least 3-connected networks. We will justify the feasibility and applicability of the proposed m-burst framework in the scenario of interest. To avoid possible collision among optical bursts launched by the MN, we define the problem of collision-free scheduling and formulate it into an integer linear program (ILP) in order to minimize the monitoring delay. Numerical results demonstrate the effectiveness of the proposed framework and the proposed solution.

  9. All-optical production of a large Bose-Einstein condensate in a double compressible crossed dipole trap

    Science.gov (United States)

    Yamashita, Kazuya; Hanasaki, Kouhei; Ando, Akihiro; Takahama, Masahiro; Kinoshita, Toshiya

    2017-01-01

    We report on an all-optical production of a 87Rb Bose-Einstein condensate (BEC) of 106 atoms. We construct a double compressible crossed dipole trap (DCDT) formed by a high-power multimode fiber laser (MCDT) and a single-mode fiber amplifier (SCDT), which are both operated at 1.06 μ m . A very cold dense gas is first cooled by polarization gradient cooling in a three-dimensional optical lattice. More than 2 ×107 atoms are loaded into the enlarged DCDT. Both CDTs are then simultaneously compressed to significantly different sizes followed by evaporation, which is performed by lowering only the MCDT power. The tighter SCDT produces an extremely high collision rate and maintains the trap stiffness, which leads to rapid and efficient evaporation. After 0.4 s, a gas of 5 ×106 atoms with a phase-space density of 0.2 is confined within the SCDT alone. Further evaporation in 2.8 s yields a nearly pure BEC of 1.2 ×106 atoms in the |F mF>=|11 > state. This number is the largest generated among all-optical methods. Our approach significantly improves the atom number of a condensate and circumvents the severe atom loss previously reported for multimode fiber lasers.

  10. An all-optical locking of a semiconductor laser to the atomic resonance line with 1 MHz accuracy.

    Science.gov (United States)

    Zhang, Xiaogang; Tao, Zhiming; Zhu, Chuanwen; Hong, Yelong; Zhuang, Wei; Chen, Jingbiao

    2013-11-18

    An all-optical locking technique without extra electrical feedback control system for a semiconductor laser has been used in stabilizing the laser frequency to a hyperfine crossover transition of 87Rb 5(2)S(1/2), F = 2 → 5(2)P(3/2), F' = 2, 3 with 1 MHz level accuracy. The optical feedback signal is generated from the narrow-band Faraday anomalous dispersion optical filter (FADOF) with nonlinear saturation effect. The peak transmission of the narrow-band FADOF corresponding to 5(2)S(1/2), F = 2 → 5(2)P(3/2), F' = 2, 3 crossover transition is 18.6 %. The bandwidth is as wide as 38.9 MHz as the laser frequency changes. After locking, the laser frequency fluctuation is reduced to 1.7 MHz. The all-optical laser locking technique can be improved to much higher accuracy with increased external cavity length. The laser we have realized can provide light exactly resonant with atomic transitions used for other atom-light interaction experiments.

  11. A novel all-optical label processing for OPS networks based on multiple OOC sequences from multiple-groups OOC

    Science.gov (United States)

    Qiu, Kun; Zhang, Chongfu; Ling, Yun; Wang, Yibo

    2007-11-01

    This paper proposes an all-optical label processing scheme using multiple optical orthogonal codes sequences (MOOCS) for optical packet switching (OPS) (MOOCS-OPS) networks, for the first time to the best of our knowledge. In this scheme, the multiple optical orthogonal codes (MOOC) from multiple-groups optical orthogonal codes (MGOOC) are permuted and combined to obtain the MOOCS for the optical labels, which are used to effectively enlarge the capacity of available optical codes for optical labels. The optical label processing (OLP) schemes are reviewed and analyzed, the principles of MOOCS-based optical labels for OPS networks are given, and analyzed, then the MOOCS-OPS topology and the key realization units of the MOOCS-based optical label packets are studied in detail, respectively. The performances of this novel all-optical label processing technology are analyzed, the corresponding simulation is performed. These analysis and results show that the proposed scheme can overcome the lack of available optical orthogonal codes (OOC)-based optical labels due to the limited number of single OOC for optical label with the short code length, and indicate that the MOOCS-OPS scheme is feasible.

  12. Low power consumption and continuously tunable all-optical microwave filter based on an opto-mechanical microring resonator.

    Science.gov (United States)

    Liu, Li; Yang, Yue; Li, Zhihua; Jin, Xing; Mo, Wenqin; Liu, Xing

    2017-01-23

    We propose and experimentally demonstrate a continuously tunable all-optical microwave filter using a silicon opto-mechanical microring resonator (MRR). By finely adjusting the pump light with submilliwatt power level, transmission spectrum of the MRR could be continuously shifted based on the nonlinear effects, including the opto-mechanical effect and thermo-optic effect. Therefore, in the case of optical single sideband (OSSB) modulation, the frequency intervals between the optical carrier (near one MRR resonance) and the corresponding resonance could be flexibly manipulated, which is the critical factor to achieve continuously tunable microwave photonic filter (MPF). In the experiment, the central frequency of the MPF could be continuously tuned from 6 GHz to 19 GHz with the pump power lower than -2.5 dBm. The proposed opto-mechanical device is competent to process microwave signals with dominant advantages, such as compact footprint, all-optical control and low power consumption. In the future, using light to control light, the opto-mechanical structure on silicon platforms might have many other potential applications in microwave systems, such as microwave switch.

  13. Discourse Preferences in Dynamic Logic

    CERN Document Server

    Jaspars, J; Jaspars, Jan; Kameyama, Megumi

    1997-01-01

    In order to enrich dynamic semantic theories with a `pragmatic' capacity, we combine dynamic and nonmonotonic (preferential) logics in a modal logic setting. We extend a fragment of Van Benthem and De Rijke's dynamic modal logic with additional preferential operators in the underlying static logic, which enables us to define defeasible (pragmatic) entailments over a given piece of discourse. We will show how this setting can be used for a dynamic logical analysis of preferential resolutions of ambiguous pronouns in discourse.

  14. Non-logic devices in logic processes

    CERN Document Server

    Ma, Yanjun

    2017-01-01

    This book shows readers how to design semiconductor devices using the most common and lowest cost logic CMOS processes.  Readers will benefit from the author’s extensive, industrial experience and the practical approach he describes for designing efficiently semiconductor devices that typically have to be implemented using specialized processes that are expensive, time-consuming, and low-yield. The author presents an integrated picture of semiconductor device physics and manufacturing techniques, as well as numerous practical examples of device designs that are tried and true.

  15. Characterising equilibrium logic and nested logic programs: Reductions and complexity

    CERN Document Server

    Pearce, David; Woltran, Stefan

    2009-01-01

    Equilibrium logic is an approach to nonmonotonic reasoning that extends the stable-model and answer-set semantics for logic programs. In particular, it includes the general case of nested logic programs, where arbitrary Boolean combinations are permitted in heads and bodies of rules, as special kinds of theories. In this paper, we present polynomial reductions of the main reasoning tasks associated with equilibrium logic and nested logic programs into quantified propositional logic, an extension of classical propositional logic where quantifications over atomic formulas are permitted. We provide reductions not only for decision problems, but also for the central semantical concepts of equilibrium logic and nested logic programs. In particular, our encodings map a given decision problem into some formula such that the latter is valid precisely in case the former holds. The basic tasks we deal with here are the consistency problem, brave reasoning, and skeptical reasoning. Additionally, we also provide encoding...

  16. Fuzzy logic in management

    CERN Document Server

    Carlsson, Christer; Fullér, Robert

    2004-01-01

    Fuzzy Logic in Management demonstrates that difficult problems and changes in the management environment can be more easily handled by bringing fuzzy logic into the practice of management. This explicit theme is developed through the book as follows: Chapter 1, "Management and Intelligent Support Technologies", is a short survey of management leadership and what can be gained from support technologies. Chapter 2, "Fuzzy Sets and Fuzzy Logic", provides a short introduction to fuzzy sets, fuzzy relations, the extension principle, fuzzy implications and linguistic variables. Chapter 3, "Group Decision Support Systems", deals with group decision making, and discusses methods for supporting the consensus reaching processes. Chapter 4, "Fuzzy Real Options for Strategic Planning", summarizes research where the fuzzy real options theory was implemented as a series of models. These models were thoroughly tested on a number of real life investments, and validated in 2001. Chapter 5, "Soft Computing Methods for Reducing...

  17. Logic Programming for Linguistics

    DEFF Research Database (Denmark)

    Christiansen, Henning

    2010-01-01

    This article gives a short introduction on how to get started with logic pro- gramming in Prolog that does not require any previous programming expe- rience. The presentation is aimed at students of linguistics, but it does not go deeper into linguistics than any student who has some ideas of what...... a computer is, can follow the text. I cannot, of course, cover all aspects of logic programming in this text, and so we give references to other sources with more details. Students of linguistics must have a very good motivation to spend time on programming, and I show here how logic programming can be used...... simpler than mainstream formalisms; this part is to a large extent based on my own research. Hardcore linguists may object that these approaches are too simplistic – and they are right (of course, they are always right ;-) – but this simplicity, I will reply, provides exposure to linguistic phenomena...

  18. VHDL for logic synthesis

    CERN Document Server

    Rushton, Andrew

    2011-01-01

    Many engineers encountering VHDL (very high speed integrated circuits hardware description language) for the first time can feel overwhelmed by it. This book bridges the gap between the VHDL language and the hardware that results from logic synthesis with clear organisation, progressing from the basics of combinational logic, types, and operators; through special structures such as tristate buses, register banks and memories, to advanced themes such as developing your own packages, writing test benches and using the full range of synthesis types. This third edition has been substantially rewritten to include the new VHDL-2008 features that enable synthesis of fixed-point and floating-point hardware. Extensively updated throughout to reflect modern logic synthesis usage, it also contains a complete case study to demonstrate the updated features. Features to this edition include: * a common VHDL subset which will work across a range of different synthesis systems, targeting a very wide range of technologies...

  19. Infinitesimals without Logic

    CERN Document Server

    Giordano, Paolo

    2009-01-01

    We introduce the ring of Fermat reals, an extension of the real field containing nilpotent infinitesimals. The construction takes inspiration from Smooth Infinitesimal Analysis (SIA), but provides a powerful theory of actual infinitesimals without any need of a background in mathematical logic. In particular, on the contrary with respect to SIA, which admits models only in intuitionistic logic, the theory of Fermat reals is consistent with classical logic. We face the problem to decide if the product of powers of nilpotent infinitesimals is zero or not, the identity principle for polynomials, the definition and properties of the total order relation. The construction is highly constructive, and every Fermat real admits a clear and order preserving geometrical representation. Using nilpotent infinitesimals, every smooth functions becomes a polynomial because in Taylor's formulas the rest is now zero. Finally, we present several applications to informal classical calculations used in Physics: now all these calc...

  20. Contextual Epistemic Logic

    CERN Document Server

    Rebuschi, Manuel

    2009-01-01

    One of the highlights of recent informal epistemology is its growing theoretical emphasis upon various notions of context. The present paper addresses the connections between knowledge and context within a formal approach. To this end, a "contextual epistemic logic", CEL, is proposed, which consists of an extension of standard S5 epistemic modal logic with appropriate reduction axioms to deal with an extra contextual operator. We describe the axiomatics and supply both a Kripkean and a dialogical semantics for CEL. An illustration of how it may fruitfully be applied to informal epistemological matters is provided.