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Reshaping force for deformed casing repairing with hydraulic rolling reshaper and its influencing factors
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作者 Hong-Fei Li Min Luo +2 位作者 Ting-Ting Xu Qiao-Zhen Li Cong-Jian Huang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2745-2757,共13页
Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years.When it is used for well repair operation,the reshaping force provided by ... Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years.When it is used for well repair operation,the reshaping force provided by ground devices is generally determined by experience.However,too large reshaping force may destroy the deformed casing,and too small reshaping force may also prolong the construction period and affect the repairing effect.In this paper,based on Hertz contact theory and elastic-plastic theory,combined with the process parameters of shaping,and considering the structural characteristics of the deformed casing and reshaper,we propose a mathematical model for calculating the reshaping force required for repairing deformed casing by hydraulic rolling reshaper.Meanwhile,the finite element model and numerical method of hydraulic rolling reshaper repairing deformed casing are established by using the finite element method,and the reliability of the mathematical model is verified by several examples.On this basis,the control variable method is used to investigate the influence of each parameter on the reshaping force,and the influence degree of each parameter is explored by orthogonal simulation test and Pearson correlation analysis.The research results not only provide an important theoretical basis for the prediction of reshaping force in on-site construction,but also provide a reference for the subsequent improvement of the shaping process. 展开更多
关键词 Hydraulic rolling reshaper reshaping force Deformed casing Casing reshaping Hertz contact theory
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High-efficiency ultra-fast all-optical photonic crystal diode based on the lateral-coupled nonlinear elliptical defect
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作者 李大星 刘凯柱 +3 位作者 余春龙 张括 刘跃钦 冯帅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期453-458,共6页
An all-optical Fano-like diode featuring a nonlinear lateral elliptical micro-cavity and a reflecting column in the photonic crystal waveguide is proposed.The asymmetric micro-cavity is constructed by removing one rod... An all-optical Fano-like diode featuring a nonlinear lateral elliptical micro-cavity and a reflecting column in the photonic crystal waveguide is proposed.The asymmetric micro-cavity is constructed by removing one rod and changing the shape of the lateral rod from a circle to an ellipse.A reflecting pillar is also introduced into the waveguide to construct an F-P cavity with the elliptical defect and enhance the asymmetric transmission for the incident light wave transmitting rightwards and leftwards,respectively.By designing the size of the ellipse and optimizing a reflecting rod at a suitable position,a maximum forward light transmittance of-1.14 dB and a minimum backward transmittance of-57.66 dB are achieved at the working wavelength of 1550.47 nm.The corresponding response time is about 10 ps when the intensity of the pump light beam resonant at 637 nm is 3.97 W/μm2. 展开更多
关键词 photonic crystal all-optical diode Fano cavity unidirectional transmission
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High-performance chiral all-optical OR logic gate based on topological edge states of valley photonic crystal
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作者 王晓蓉 费宏明 +6 位作者 林瀚 武敏 康丽娟 张明达 刘欣 杨毅彪 肖连团 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期392-398,共7页
For all-optical communication and information processing,it is necessary to develop all-optical logic gates based on photonic structures that can directly perform logic operations.All-optical logic gates have been dem... For all-optical communication and information processing,it is necessary to develop all-optical logic gates based on photonic structures that can directly perform logic operations.All-optical logic gates have been demonstrated based on conventional waveguides and interferometry,as well as photonic crystal structures.Nonetheless,any defects in those structures will introduce high scattering loss,which compromises the fidelity and contrast ratio of the information process.Based on the spin-valley locking effect that can achieve defect-immune unidirectional transmission of topological edge states in valley photonic crystals(VPCs),we propose a high-performance all-optical logic OR gate based on a VPC structure.By tuning the working bandwidth of the two input channels,we prevent interference between the two channels to achieve a stable and high-fidelity output.The transmittance of both channels is higher than 0.8,and a high contrast ratio of 28.8 dB is achieved.Moreover,the chirality of the logic gate originated from the spin-valley locking effect allows using different circularly polarized light as inputs,representing“1”or“0”,which is highly desired in quantum computing.The device’s footprint is 18μm×12μm,allowing high-density on-chip integration.In addition,this design can be experimentally fabricated using current nanofabrication techniques and will have potential applications in optical communication,information processing,and quantum computing. 展开更多
关键词 topological photonics topological edge state valley photonic crystal all-optical logic gate
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All-Optical Sampling Using Nonlinear Polarization Rotation in a Single Semiconductor Optical Amplifier 被引量:2
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作者 张尚剑 张谦述 +2 位作者 李和平 刘永智 刘永 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1031-1035,共5页
We propose a novel all-optical sampling method using nonlinear polarization rotation in a semiconductor optical amplifier. A rate-equation model capable of describing the all-optical sampling mechanism is presented in... We propose a novel all-optical sampling method using nonlinear polarization rotation in a semiconductor optical amplifier. A rate-equation model capable of describing the all-optical sampling mechanism is presented in this paper. Based on this model, we investigate the optimized operating parameters of the proposed system by simulating the output intensity of the probe light as functions of the input polarization angle, the phase induced by the polarization controller, and the ori- entation of the polarization beam splitter. The simulated results show that we can obtain a good linear slope and a large linear dynamic range,which is suitable for all-optical sampling. The operating power of the pump light can be less than lmW. The presented all-optical sampling method can potentially operate at a sampling rate up to hundreds GS/s and needs low optical power. 展开更多
关键词 optical signal processing all-optical sampling semiconductor optical amplifier nonlinear polarization rotation
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Optically Digitalized Holography: A Perspective for All-Optical Machine Learning 被引量:5
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作者 Min Gu Xinyuan Fang +1 位作者 Haoran Ren Elena Goi 《Engineering》 SCIE EI 2019年第3期363-365,共3页
Holography, which was invented by Dennis Gabor in 1948, offers an approach to reconstructing both the amplitude and phase information of a three-dimensional (3D) object [1]. Since its invention, the concept of hologra... Holography, which was invented by Dennis Gabor in 1948, offers an approach to reconstructing both the amplitude and phase information of a three-dimensional (3D) object [1]. Since its invention, the concept of holography has been widely used in various fields, such as microscopy [2], interferometry [3], ultrasonography [4], and holographic display [5]. Optical holography can be divided into two steps: recording and reconstruction. A conventional hologram is recorded onto a photosensitive film as the interference between an object beam carrying the 3D object information and a reference beam. Thereafter, the original object wavefront is reconstructed in the 3D image space by illuminating the reference beam on the recorded hologram. 展开更多
关键词 all-optical MACHINE Optically Digitalized HOLOGRAPHY
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All-optical computing based on convolutional neural networks 被引量:7
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作者 Kun Liao Ye Chen +7 位作者 Zhongcheng Yu Xiaoyong Hu Xingyuan Wang Cuicui Lu Hongtao Lin Qingyang Du Juejun Hu Qihuang Gong 《Opto-Electronic Advances》 SCIE 2021年第11期46-54,共9页
The rapid development of information technology has fueled an ever-increasing demand for ultrafast and ultralow-en-ergy-consumption computing.Existing computing instruments are pre-dominantly electronic processors,whi... The rapid development of information technology has fueled an ever-increasing demand for ultrafast and ultralow-en-ergy-consumption computing.Existing computing instruments are pre-dominantly electronic processors,which use elec-trons as information carriers and possess von Neumann architecture featured by physical separation of storage and pro-cessing.The scaling of computing speed is limited not only by data transfer between memory and processing units,but also by RC delay associated with integrated circuits.Moreover,excessive heating due to Ohmic losses is becoming a severe bottleneck for both speed and power consumption scaling.Using photons as information carriers is a promising alternative.Owing to the weak third-order optical nonlinearity of conventional materials,building integrated photonic com-puting chips under traditional von Neumann architecture has been a challenge.Here,we report a new all-optical comput-ing framework to realize ultrafast and ultralow-energy-consumption all-optical computing based on convolutional neural networks.The device is constructed from cascaded silicon Y-shaped waveguides with side-coupled silicon waveguide segments which we termed“weight modulators”to enable complete phase and amplitude control in each waveguide branch.The generic device concept can be used for equation solving,multifunctional logic operations as well as many other mathematical operations.Multiple computing functions including transcendental equation solvers,multifarious logic gate operators,and half-adders were experimentally demonstrated to validate the all-optical computing performances.The time-of-flight of light through the network structure corresponds to an ultrafast computing time of the order of several picoseconds with an ultralow energy consumption of dozens of femtojoules per bit.Our approach can be further expan-ded to fulfill other complex computing tasks based on non-von Neumann architectures and thus paves a new way for on-chip all-optical computing. 展开更多
关键词 convolutional neural networks all-optical computing mathematical operations cascaded silicon waveguides
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All-optically integrated photoacoustic and optical coherence tomography:A review 被引量:3
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作者 Wei Qiao Zhongjiang Chen 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2017年第4期42-51,共10页
All-optically integrated photoacoustic(PA)and optical coherence tomography(OCT)dualmode imaging technology that could o®er comprehensive pathological information for accurate diagnosis in clinic has gradually bec... All-optically integrated photoacoustic(PA)and optical coherence tomography(OCT)dualmode imaging technology that could o®er comprehensive pathological information for accurate diagnosis in clinic has gradually become a promising imaging technology in the aspect of biomedical imaging during the recent years.This review refers to the technology aspects of alloptical PA detection and system evolution of optically integrated PA and OCT,including Michelson interferometer dual-mode imaging system,Fabry–Perot(FP)interferometer dualmode imaging system and Mach–Zehnder interferometer dual-mode imaging system.It is believed that the optically integrated PA and OCT has great potential applications in biomedical imaging. 展开更多
关键词 all-optical PHOTOACOUSTIC optical coherence tomography dual-mode imaging
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All-optical logic devices based on black arsenic-phosphorus with strong nonlinear optical response and high stability 被引量:3
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作者 Leiming Wu Taojian Fan +10 位作者 Songrui Wei Yijun Xu Ye Zhang Dingtao Ma Yiqing Shu Yuanjiang Xiang Jun Liu Jianqing Li Krassimir Panajotov Yuwen Qin Han Zhang 《Opto-Electronic Advances》 SCIE EI 2022年第1期13-23,共11页
The Kerr nonlinearity in two-dimensional(2D)nanomaterials is emerging as an appealing and intriguing research area due to their prominent light processing,modulation,and manipulation abilities.In this contribution,2D ... The Kerr nonlinearity in two-dimensional(2D)nanomaterials is emerging as an appealing and intriguing research area due to their prominent light processing,modulation,and manipulation abilities.In this contribution,2D black arsenic-phosphorus(B-AsP)nanosheets(NSs)were applied in nonlinear photonic devices based on spatial self-phase modula-tion(SSPM)method.By applying the Kerr nonlinearity in 2D B-AsP,an all-optical phase-modulated system is proposed to realize the functions of“on”and“off”in all-optical switching.By using the same all-optical phase-modulated system,another optical logic gate is proposed,and the logical“or”function is obtained based on the 2D B-AsP NSs dispersions.Moreover,by using the SSPM method,a 2D B-AsP/SnS_(2) hybrid structure is fabricated,and the result illustrates that the hybrid structure possesses the ability of the unidirectional nonlinear excitation,which helps in obtaining the function of spatial asymmetric light propagation.This function is considered an important prerequisite for the realization of diode functionalization,which is believed to be a factor in important basis for the design of isolators as well.The initial investig-ations indicate that 2D B-AsP is applicable for designing optical logical devices,which can be considered as an import-ant development in all-optical information processing. 展开更多
关键词 B-AsP nanomaterial all-optical phase-modulated system spatial asymmetric light propagation
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Mid-infrared supercontinuum generation and its application on all-optical quantization with different input pulses 被引量:1
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作者 Yan Li Xinzhu Sang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期126-133,共8页
Supercontinuum generation(SCG) and its application on all-optical quantization of all-optical analog-to-digital conversions(AOADCs) at the mid-infrared region in an Al GaAs strip waveguide are investigated numerically... Supercontinuum generation(SCG) and its application on all-optical quantization of all-optical analog-to-digital conversions(AOADCs) at the mid-infrared region in an Al GaAs strip waveguide are investigated numerically. The simulation results show that when the parabolic pulse is input, not only broader and higher-coherence SCG is obtained and a higher effective number of bits(ENOB) can be achieved, compared with the input pulse with hyperbolic-secant and Gaussian shaping. A four-bit quantization resolution is achieved along with a signal-to-noise ratio of 24.02 dB and an ENOB of3.99 bit, and the required input peak power is 760 mW. 展开更多
关键词 MID-INFRARED SUPERCONTINUUM generation all-optical QUANTIZATION
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All-optical switching and nonlinear optical properties of HBT in ethanol solution 被引量:3
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作者 郑加金 张桂兰 +2 位作者 郭阳雪 李向平 陈文驹 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第4期1047-1051,共5页
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... 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. 展开更多
关键词 all-optical switching 2-(2'-hydroxyphenyl benzothiazole ESIPT nonlinear optical properties
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Boron quantum dots all-optical modulator based on efficient photothermal effect 被引量:2
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作者 Cong Wang Qianyuan Chen +8 位作者 Hualong Chen Jun Liu Yufeng Song Jie Liu Delong Li Yanqi Ge Youning Gong Yupeng Zhang Han Zhang 《Opto-Electronic Advances》 SCIE 2021年第7期33-42,共10页
All-optical devices without external electronic components have drawn extraordinary attentions in all-optical communication.In this work,boron quantum dots(BQDs)were synthesized by a facile liquid-phase exfoliation me... All-optical devices without external electronic components have drawn extraordinary attentions in all-optical communication.In this work,boron quantum dots(BQDs)were synthesized by a facile liquid-phase exfoliation method.The as-prepared BQDs showed good structural homogeneity and crystallinity,broadband optical absorption as well as excellent photothermal properties.Femtosecond-resolved transient absorption further revealed the short carrier relaxation time of BQDs.Inspired by the outstanding photothermal properties and ultrafast carrier dynamic of BQDs,we fabricated BQDsbased all-optical modulator.The phase shift with a slope efficiency of 0.032π/m W and response time of 0.97 ms can be achieved.The modulator was used in laser resonance cavity to achieve all-optical actively Q-switched laser operation with control repetition rate.This prototypical BQDs-based all-optical modulator shows a great potential to be applied in all-optical information processing and communication. 展开更多
关键词 boron quantum dots all-optical modulator photothermal conversion actively Q-switched laser
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Controllable all-optical stochastic logic gates and their delay storages based on the cascaded VCSELs with optical-injection 被引量:5
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作者 钟东洲 罗伟 许葛亮 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期342-354,共13页
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 ve... 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. 展开更多
关键词 all-optical stochastic logic gates delay storage polarization bistable success probability
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Setup of a dipole trap for all-optical trapping 被引量:1
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作者 Miao Wang Zheng Chen +2 位作者 Yao Huang Hua Guan Ke-Lin Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期362-366,共5页
Micromotion induced by the radio-frequency field contributes greatly to the systematic frequency shifts of optical frequency standards.Although different strategies for mitigating this effect have been proposed,trappi... Micromotion induced by the radio-frequency field contributes greatly to the systematic frequency shifts of optical frequency standards.Although different strategies for mitigating this effect have been proposed,trapping ions optically has the potential to provide a generic solution to the elimination of micromotion.This could be achieved by trapping a single ion in the dipole trap composed of a highpower laser field.Here,we present the setup of the dipole trap composed of a 532 nm laser at a power of 10 W aiming to optically trap a single^(40)Ca^(+)and we observe an AC-Stark shift of the fluorescence spectrum line of~22 MHz caused by the 532 nm dipole beam.The beam waist of the dipole laser is several microns,which would provide a dipole potential strong enough for all-optical trapping of a single^(40)Ca^(+)ion. 展开更多
关键词 dipole trap AC-Stark shift trap depth all-optical trapping
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All-Optical Vector Cesium Magnetometer 被引量:2
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作者 孙伟民 黄强 +2 位作者 黄宗军 王平稳 张军海 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期124-127,共4页
Based on power modulation of a pump laser and precessional projection detection, we present an all-optical vector magnetometer of cesium, which has a demonstrated magnitude sensitivity of 80fF/Hz^1/2 and an orientatio... Based on power modulation of a pump laser and precessional projection detection, we present an all-optical vector magnetometer of cesium, which has a demonstrated magnitude sensitivity of 80fF/Hz^1/2 and an orientation sensitivity of 0.1°/Hz^1/2. In the device, four main factors are measured experimentally, which are the Larmor precession frequency of a polarized magnetic moment that depends on the modulus of the measured m^gnetic field only, two phase shifts and amplitude ratio of the precession projection in the two probe directions relative to the magnetic field orientation. This kind of magnetometer with high sensitivity in the range of the spatial angle is suitable for solving the inverse problem and geomagnetic navigation. 展开更多
关键词 all-optical Vector Cesium Magnetometer
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Enhancement of modulation depth of an all-optical switch using an azo dye-ethyl red film 被引量:1
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作者 陆文强 陈桂英 +3 位作者 郝召锋 许京军 田建国 张春平 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期429-436,共8页
The polymethyl methacrylate (PMMA) film doped with an azo dye ethyl-red (ER) film is employed to demonstrate the properties of an all-optical switch by its photoinduced dichroism and birefringence. We show how to ... The polymethyl methacrylate (PMMA) film doped with an azo dye ethyl-red (ER) film is employed to demonstrate the properties of an all-optical switch by its photoinduced dichroism and birefringence. We show how to enhance remarkably the modulation depth of all-optical switches almost to 100% by using two linear polarization beams: one beam is inclined at 45° with respect to the probing beam and serves as a pumping beam, and the other beam is perpendicular to the probing beam and used as an erasing beam. Furthermore, a maximum-to-minimum output intensity ratio of 2000:1 is achieved in experiment, which is very useful and important for optical storages and image displays. 展开更多
关键词 all-optical switch azo dye ethyl-red film modulation depth
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Six-bit all-optical quantization using photonic crystal fiber with soliton self-frequency shift and pre-chirp spectral compression techniques 被引量:1
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作者 康哲 苑金辉 +4 位作者 李莎 解松霖 颜玢玢 桑新柱 余重秀 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期345-349,共5页
In this paper, we propose an optical quantization scheme for all-optical analog-to-digital conversion that facilitates photonics integration. A segment of 10-m photonic crystal fiber with a high nonlinear coefficient ... In this paper, we propose an optical quantization scheme for all-optical analog-to-digital conversion that facilitates photonics integration. A segment of 10-m photonic crystal fiber with a high nonlinear coefficient of 62.8 W-1/kin is utilized to realize large scale soliton self-frequency shift relevant to the power of the sampled optical signal. Furthermore, a 100-m dispersion-increasing fiber is used as the spectral compression module for further resolution enhancement. Simulation results show that 317-nm maximum wavelength shift is realized with 1550-nm initial wavelength and 6-bit quantization resolution is obtained with a subsequent spectral compression process. 展开更多
关键词 all-optical analog-to-digital conversion photonic crystal fiber soliton self-frequency shift spectralcompression
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Research on Fault Repair Method of All-Optical Network Based on SDN 被引量:1
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作者 Zhongnan Zhao Huiqiang Wang +1 位作者 Jian Wang Hongwei Guo 《China Communications》 SCIE CSCD 2020年第6期180-195,共16页
All-optical network,as a new backbone network,is featured with high speed and large capacity transmission.It may be out of order due to various faults while providing high-performance transmission service,thus more ef... All-optical network,as a new backbone network,is featured with high speed and large capacity transmission.It may be out of order due to various faults while providing high-performance transmission service,thus more effective fault repairing methods are required.A routing and wavelength assignment method based on SDN is designed and analyzed from the perspective of service function chaining in this paper.A multi-objective integer linear programming model based on impairment-aware and scheduling time is constructed by combining the unified control of control plane with the resource allocation mode of service function virtualization.Meanwhile,an improved Firefly Algorithm is adopted to solve the model for obtaining a better scheduling scheme,so as to the resources are allocated on-demand in a more flexible and efficient way,which effectively improved the self-recovery capability of the network.In the simulation experiments,Through the comparison between the method proposed and methods based on centralization and distribution,method proposed in the paper is superior to the compared ones in the indexes of survivability,blocking probability,link recovery time,and presents a better scheduling performance,makes the system has stronger ability of self-healing in the face of failure. 展开更多
关键词 SDN all-optical network fault repair routing and wavelength assignment
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Optimizational 6-bit all-optical quantization with soliton self-frequency shift and pre-chirp spectral compression techniques based on photonic crystal fiber 被引量:1
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作者 李莎 王建萍 +1 位作者 康哲 余重秀 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期381-385,共5页
In this paper, we optimize a proposed all-optical quantization scheme based on soliton self-frequency shift(SSFS)and pre-chirp spectral compression techniques. A 10m-long high-nonlinear photonic crystal fiber(PCF) is ... In this paper, we optimize a proposed all-optical quantization scheme based on soliton self-frequency shift(SSFS)and pre-chirp spectral compression techniques. A 10m-long high-nonlinear photonic crystal fiber(PCF) is used as an SSFS medium relevant to the power of the sampled optical pulses. Furthermore, a 10m-long dispersion flattened hybrid cladding hexagonal-octagonal PCF(6/8-PCF) is utilized as a spectral compression medium to further enhance the resolution. Simulation results show that 6-bit quantization resolution is still obtained when a 100m-long dispersion-increasing fiber(DIF)is replaced by a 6/8-PCF in spectral compression module. 展开更多
关键词 all-optical analog-to-digital conversion soliton self-frequency shift spectral compression photonic crystal fiber
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Novel Scheme of All-optical AND Gate Based on Fabry-Perot Semiconductor Optical Amplifier
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作者 ZHANG Wei QIU Kun LING Yun PANG Ying 《Semiconductor Photonics and Technology》 CAS 2007年第1期63-68,共6页
A novel scheme of all-optical AND gate based on a Fabry-Perot semiconductor optical amplifier(FP-SOA) is proposed and its feasibility is verified by simulation. Using this scheme, all-optical AND gate can be realized ... A novel scheme of all-optical AND gate based on a Fabry-Perot semiconductor optical amplifier(FP-SOA) is proposed and its feasibility is verified by simulation. Using this scheme, all-optical AND gate can be realized with the extinction ratio of 10 dB. The influence of pulse interval and pulse width on the extinction ratio is also investigated. 展开更多
关键词 all-optical packet switching all-optical signal processing all-optical AND gate FP-SOA
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All-optical switchings of 3-hydroxyflavone in different solvents
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作者 吴峰 林列 +3 位作者 李向平 于雅鑫 张桂兰 陈文驹 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第4期1461-1466,共6页
3-hydroxyflavone (3-HF) is an organic molecule with an excited-stated intramolecular proton transfer (ESIPT) effect. All-optical switchings and beam deflections of 3-HF in three kinds of solvents (cyclohexane, et... 3-hydroxyflavone (3-HF) is an organic molecule with an excited-stated intramolecular proton transfer (ESIPT) effect. All-optical switchings and beam deflections of 3-HF in three kinds of solvents (cyclohexane, ethanol and dimethyl sulfoxide) have been investigated by using the third-harmonic generation (355 nm) of a mode-locked Nd:YAG laser as a pump beam and a continuous-wave (cw) He-Ne laser (632.8 nm) as a probe beam. The nonlinear refractive indices of 3-HF in the three different solvents are determined by using the Z-scan technique under an ultraviolet (UV) pump beam at a wavelength of 355 nm. It has been found that the optical switching and beam deflection effects result from the change in refractive index of 3-HF under the irradiation of the pump beam. On the basis of the analyses of absorption spectra and fluorescence spectra, we conclude that the change in refractive index of 3-HF is due to not the thermal effect but the ESIPT effect of 3-HF under the pump beam. As the ESIPT is exceedingly fast, 3-HF might be an excellent candidate for high-speed optical switching. 展开更多
关键词 all-optical switching 3-hydroxyflavone ESIPT NONLINEAR
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