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一种新的双光系统透明电极电池
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作者 毕只初 钱越英 《感光科学与光化学》 CSCD 1989年第1期73-76,共4页
植物光合作用在其叶绿体的光合作用膜上进行。它有两个串联着的光系统(PSII和PSI)。PSII在膜的一侧,吸收波长相当于680nm的光子激发电子并产生空穴,空穴将水氧化得氧。电子经过一系列的下坡传送,暗反应合成ATP,到处于膜另一侧的PSI。PS... 植物光合作用在其叶绿体的光合作用膜上进行。它有两个串联着的光系统(PSII和PSI)。PSII在膜的一侧,吸收波长相当于680nm的光子激发电子并产生空穴,空穴将水氧化得氧。电子经过一系列的下坡传送,暗反应合成ATP,到处于膜另一侧的PSI。PSI吸收波长相当于700nm的光子,再次将电子激发,经过第二个系列的下坡传送,暗反应将NADP还原为NADHP。NADHP和ATP最终将CO_2还原为碳水化合物。 展开更多
关键词 光电化电池 透明 电极 双光系统
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双光瞳系统的光学传递函数和扫描全息术 被引量:6
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作者 梁万国 谢敬辉 +1 位作者 赵达尊 赵业玲 《北京理工大学学报》 EI CAS CSCD 1997年第2期226-229,共4页
在单光瞳图像处理系统中,扫描系统与非相干成像系统具有等价性,在此基础上设计了图像处理系统中的双光瞳处理系统,并推导了该系统在聚焦和离焦时的光学传递函数,提出了离焦时该系统在光学扫描全息术中的应用.
关键词 双光系统 光学传递函数 扫描全息术
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双光腔光机械系统的动力学相变和选择性能量交换 被引量:1
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作者 刘妮 张小芳 梁九卿 《物理学报》 SCIE EI CAS CSCD 北大核心 2021年第14期17-29,共13页
本文探究了单腔和双腔光机械装置的动力学相变和选择性能量交换.发现系统会经历类似于Dicke-Hepp-Lieb超辐射型的动力学相变,且两光场间的正交动量耦合出现一个新的动力学临界点.两光场间的正交动量耦合等价于单(双)模光机械系统的外场... 本文探究了单腔和双腔光机械装置的动力学相变和选择性能量交换.发现系统会经历类似于Dicke-Hepp-Lieb超辐射型的动力学相变,且两光场间的正交动量耦合出现一个新的动力学临界点.两光场间的正交动量耦合等价于单(双)模光机械系统的外场驱动.通过耦合参数的调控,系统可以实现任意两模间的选择性能量交换,且临界耦合点与选择性能量交换对应.模压缩是能量转换的标志,且任何两模的正交压缩由特定玻色模间的能量交换决定. 展开更多
关键词 双光腔光机械系统 相变 选择性能量交换 模压缩
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智能移动双光监测系统在泛在电力物联网中的应用研究 被引量:4
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作者 余敏 李永腾 +2 位作者 葛志峰 郭鹏程 柏帆 《电子设计工程》 2020年第13期179-183,共5页
在泛在电力物联网的环境下,电力工程领域对红外检测与视频捕捉等技术提出了更高的要求。文中设计开发了一种联合红外热成像与可见光视频的智能移动双光检测系统。该系统基于5G通信技术,将温度监测与视频控制功能相结合,采集电路把光信... 在泛在电力物联网的环境下,电力工程领域对红外检测与视频捕捉等技术提出了更高的要求。文中设计开发了一种联合红外热成像与可见光视频的智能移动双光检测系统。该系统基于5G通信技术,将温度监测与视频控制功能相结合,采集电路把光信号转换成电信号,并进行红外热辐射的数模转换,综合具有设备管理功能、温度监测功能、电子地图等功能。软件终端控制系统由硬件驱动层、功能模块层、业务逻辑层组成,总体采用C/S构架,以多线程的方式为监控单元提供服务。应用测试结果表明,该系统运行稳定、性能良好,可以广泛应用于泛在电力物联网中。 展开更多
关键词 泛在电力物流网 红外热成像 视频监控 双光监测系统
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双光楔光轴指向调整技术 被引量:5
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作者 高飞 王苗 《光电工程》 CAS CSCD 北大核心 2018年第11期57-63,共7页
由于双光楔系统可以精确调整光轴的指向,而且具有结构简单紧凑、调整速度快、偏转角度大的优点。为了满足某产品的需要,实现同心圆和Z字型的光轴调整轨迹。本文根据现有理论,通过建立光轴偏转角度与双光楔转动角度关系模型,推导出对应公... 由于双光楔系统可以精确调整光轴的指向,而且具有结构简单紧凑、调整速度快、偏转角度大的优点。为了满足某产品的需要,实现同心圆和Z字型的光轴调整轨迹。本文根据现有理论,通过建立光轴偏转角度与双光楔转动角度关系模型,推导出对应公式,并结合Matlab仿真、拟合和实际的产品测试,设计出了利用ARM与计算机控制双光楔来调整光轴指向的方案。结果表明,该方案光轴指向调整的误差小于0.5°,能够实现预期的轨迹,满足实际产品的需求。 展开更多
关键词 光轴指向调整 双光系统 双光楔扫描 ARM
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Spectra of Free Diquark in the Bethe-Salpeter Approach 被引量:1
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作者 YU Yan-Ming KE Hong-Wei +5 位作者 DING Yi-Bing GUO Xin-Heng JIN Hong-Ying LI Xue-Qian SHEN Peng- Nian WANG Guo-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6X期1031-1039,共9页
In this work, we employ the Bethe-Salpeter (B-S) equation to investigate the spectra of free diquarks and their B-S wave functions. We find that the B-S approach can be consistently applied to study the diqaurks wit... In this work, we employ the Bethe-Salpeter (B-S) equation to investigate the spectra of free diquarks and their B-S wave functions. We find that the B-S approach can be consistently applied to study the diqaurks with two heavy quarks or one heavy and one light quarks, but for two light-quark systems, the results are not reliable. There are a few free parameters in the whole scenario which can only be fixed phenomenologically. Thus, to determine them, one has to study baryons which are composed of quarks and diquarks. 展开更多
关键词 Bethe-Salpeter equation DIQUARK SPECTRA
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Observation of interface of two kinds of bi-metal composite parts prepared by thixo-forging 被引量:4
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作者 杨昭 周丽 董建雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1579-1584,共6页
Two kinds of bi-metal composite parts (Sn-15%Pb and Pb-22%Sn bi-metal system, and Al-7%Si and SiCp/6061 MMC bi-metal system) were prepared by the strain-induced melt activated thixo-forging. The interfaces of the bi... Two kinds of bi-metal composite parts (Sn-15%Pb and Pb-22%Sn bi-metal system, and Al-7%Si and SiCp/6061 MMC bi-metal system) were prepared by the strain-induced melt activated thixo-forging. The interfaces of the bi-metal composites were observed by OM and SEM. The observations show that the semisolid metals keep independence during thixo-forging. The solid phases in the semisolid slurries maintain their original morphologies after thixo-forging. The liquid phases near the interface mix together and form a thin layer. The interfaces are bonded firmly with the metallurgical bonding. No oxide layers are found at the interfaces. Strengths of the interfaces were investigated by the micro-hardness test. The experimental results show that the composite interfaces have high strength. However, the agglomerated enhancing particles cause fine defect on the interface of the Al-7%Si and SiCr/6061 MMC bi-metal composite. 展开更多
关键词 semisolid metal processing bi-metal composite thixo-forming die-forging metal matrix composite
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A High Spectral Efficiency System Enabled by Free Window with Full Duplex 被引量:1
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作者 Feng Cheng Cui Hongyu +1 位作者 Ma Meng Jiao Bingli 《China Communications》 SCIE CSCD 2015年第9期93-99,共7页
This paper studies the capacity issues of a wireless communication system that implements single channel full duplex(SCFD) communication at the base station(BS), thereby the mobile stations share the channel via time ... This paper studies the capacity issues of a wireless communication system that implements single channel full duplex(SCFD) communication at the base station(BS), thereby the mobile stations share the channel via time division duplex(TDD). The system makes use of the same setup as has been used in previous studies of SCFD, but unlike these previous systems, the new system uses water-filling to maximize the spectral efficiency of the uplink channel. The concept of a free window is introduced to the duplex model for measuring, intuitively, the effective bandwidth of the bi-directional communication. The capacity gain is calculated and numerical results show the advantage of the proposed system over that of conventional TDD. 展开更多
关键词 spectral efficiency free window time division duplex full duplex water-filling
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Roll-to-roll imprint for high precision grating manufacturing 被引量:3
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作者 Liu Hongzhong Shi Yongsheng +2 位作者 Yin Lei Jiang Weitao Lu Bingheng 《Engineering Sciences》 EI 2013年第1期39-43,共5页
In this paper,a novel roll-to-roll imprint process is proposed to fabricate gratings in large area. The key challenges in roll-to-roll imprint process,such as the roller mold preparation,imprint system,misalignment of... In this paper,a novel roll-to-roll imprint process is proposed to fabricate gratings in large area. The key challenges in roll-to-roll imprint process,such as the roller mold preparation,imprint system,misalignment of imprint roller and backup roller,and also the imprint pressure,are investigated. Various gratings with different periods and profiles are obtained by the roll-to-roll process. To calibrate the measuring ability of the self-made grating by imprint,a calibration system is built with a dual-frequency laser interferometer. By the calibration,the self-made gratings can achieve ±4μm accuracy in 45mm measuring distance. 展开更多
关键词 high-precision gratings roll-to-roll imprint MISALIGNMENT roller mold
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Two-function light source in a FBG multi-point sensing system
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作者 HE Shi-ya DENG Yan-hao YU Yang HU Shu-yang GUAN Zheng 《Optoelectronics Letters》 EI 2007年第3期219-221,共3页
In this paper,a two-function light source is recommended. It can both amplify the light power and demodulate the wave-length signal. Its output power is 1000 times as high as traditional broadband light source(BBS) an... In this paper,a two-function light source is recommended. It can both amplify the light power and demodulate the wave-length signal. Its output power is 1000 times as high as traditional broadband light source(BBS) and it can demodulate the signal by scanning wavelength in 30 nm of bandwidth range in the situation of 1550 nm central wavelength. This kind of light source effectively solves the problem of light energy supply in more-point measurement of FBG and simplifies the structure of sensing measurement. 展开更多
关键词 双功能光源 FBG 多点传感系统 光纤光栅 波分复用
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Influence of a Single Frequency Electromagnetic Wave on Energy Spectrum of Nonpolariton System in a Kerr Nonlinear Blackbody
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作者 曾奇军 成泽 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1149-1154,共6页
In a Kerr nonlinear blackbody, bare photons with opposite wave vectors and helieities are bound into pairs and unpaired photons are transformed into a different kind of quasiparticle, the nonpolariton. The present pap... In a Kerr nonlinear blackbody, bare photons with opposite wave vectors and helieities are bound into pairs and unpaired photons are transformed into a different kind of quasiparticle, the nonpolariton. The present paper investigates the influence of a single frequency electromagnetic wave on the energy spectrum of the nonpolariton system. We find that the wave can lead to an energy shift of nonpolaritons. Moreover, we calculate the first-order energy shift on certain conditions. 展开更多
关键词 Kerr nonlinear blackbody nonpolariton PERTURBATION energy shift
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Entanglement for a Bimodal Cavity Field Interacting with a Two-Level Atom
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作者 LIU Jia CHEN Zi-Yu BU Shen-Ping ZHANG Guo-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期133-136,共4页
Negativity has been adopted to investigate the entanglement in a system composed of a two-level atom anda two-mode cavity field.Effects of Kerr-like medium and the number of photon inside the cavity on the entanglemen... Negativity has been adopted to investigate the entanglement in a system composed of a two-level atom anda two-mode cavity field.Effects of Kerr-like medium and the number of photon inside the cavity on the entanglementare studied.Our results show that atomic initial state must be superposed,so that the two cavity field modes can beentangled.Moreover,we also conclude that the number of photon in the two cavity mode should be equal.The interactionbetween modes,namely,the Kerr effect,has a significant negative contribution.Note that the atom frequency and thecavity frequency have an indistinguishable effect,so a corresponding approximation has been made in this article.Theseresults may be useful for quantum information in optics systems. 展开更多
关键词 NEGATIVITY Kerr-like medium Jaynes-Cummings model
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Comparison of Solar Trackers and Application of a Sensor Less Dual Axis Solar Tracker
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作者 Ceyda Aksoy Tirmikci Cenk Yavuz 《Journal of Energy and Power Engineering》 2015年第6期556-561,共6页
In the 21th century, one of the biggest problems that the world faces is energy provision. Today, the way that most countries use for energy production is not clean and continuous. The most obvious proof for that is t... In the 21th century, one of the biggest problems that the world faces is energy provision. Today, the way that most countries use for energy production is not clean and continuous. The most obvious proof for that is the change in the climate. The amount of CO2 (carbon dioxide) that is caused by fossil fuel burning increases day by day and this situation creates the greenhouse effect and change in the climate. The sun is one of the best solutions to this problem. It is not only clean and continuous, but also available anywhere, anytime. However, the efficiency of a photovoltaic system is directly related to the amount of solar energy acquired by the system which means that, it is necessary to follow the sun to have a high efficient system. There are two types of trackers that follow the sun and there are several ways to build them. In this paper, solar tracker designs are examined and a new dual axis solar tracker design is given. 展开更多
关键词 Solar energy sensorless solar tracker solar math linear actuators efficiency low cost.
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Inhibition of Two-Photon Absorption in a Four-Level Atomic System with Closed-Loop Configuration
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作者 JIN Li-Xia LI Jia-Hua QI Chun-Chao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5期916-920,共5页
We theoretically investigate the features of two-photon absorption in a coherently driven four-level atomic system with closed-loop configuration. It is found that two-photon absorption can be completely suppressed ju... We theoretically investigate the features of two-photon absorption in a coherently driven four-level atomic system with closed-loop configuration. It is found that two-photon absorption can be completely suppressed just by properly adjusting the relative phase of four coherent low-intensity driving fields and the atomic system becomes trans- parent against two-photon absorption. From a physical point of view, we explicitly explain these results in terms of quantum interference induced by two different two-photon excitation channels. 展开更多
关键词 two-photon absorption quantum interference closed-loop configuration
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Local Control of Two-Photon Absorption in a Six-Level Atomic System by Using a Coherent Perturbation Field
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作者 JIA Wen-Zhi WANG Shun-Jin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期929-935,共7页
If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-level K-type atom with another higher excited level, the two-photon electromagnetically induced transparency ... If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-level K-type atom with another higher excited level, the two-photon electromagnetically induced transparency can be locally modulated by altering the parameters of the additional perturbation field. With different detunings of the coherent perturbation field, the absorption peak or transparency window with sharp and high-contrast speetrM feature can be generated in the two-photon absorption spectrum. The physical interpretation of these phenomena is given in terms of the dressed states. 展开更多
关键词 dressed states electromagnetically induced transparency coherent perturbation field
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Development of Fiber-Optic Current Sensing Technique and Its Applications in Electric Power Systems 被引量:10
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作者 Kiyoshi Kurosawa (1) 《Photonic Sensors》 SCIE EI CAS 2014年第1期12-20,共9页
This paperdescribes the development and applications of a fiber-optic electric current sensing technique with the stable properties and compact, simple, and flexible structure of the sensing device. The special charac... This paperdescribes the development and applications of a fiber-optic electric current sensing technique with the stable properties and compact, simple, and flexible structure of the sensing device. The special characteristics of the sensors were achieved by use of the special low birefringence fiber as the Faraday-effect sensing element and were also achieved with creation of sensing schemes which matched with the features of the fiber. Making use of the excellent features of the sensing technique, various current monitoring devices and systems were developed and applied practically for the control and maintenance in the electric power facility. In this paper, the design and performance of the sensing devices are introduced first. After that, examples of the application systems practically applied are also introduced, including fault section/point location systems for power transmission cable lines. 展开更多
关键词 CURRENT SENSOR FIBER Faraday-effect POWER application
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Local Smooth Solutions to the 3-Dimensional Isentropic Relativistic Euler equations 被引量:3
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作者 Yongcai GENG Yachun LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第2期301-318,共18页
The authors consider the local smooth solutions to the isentropic relativistic Euler equations in(3+1)-dimensional space-time for both non-vacuum and vacuum cases.The local existence is proved by symmetrizing the syst... The authors consider the local smooth solutions to the isentropic relativistic Euler equations in(3+1)-dimensional space-time for both non-vacuum and vacuum cases.The local existence is proved by symmetrizing the system and applying the FriedrichsLax-Kato theory of symmetric hyperbolic systems.For the non-vacuum case,according to Godunov,firstly a strictly convex entropy function is solved out,then a suitable symmetrizer to symmetrize the system is constructed.For the vacuum case,since the coefficient matrix blows-up near the vacuum,the authors use another symmetrization which is based on the generalized Riemann invariants and the normalized velocity. 展开更多
关键词 Isentropic relativistic Euler equations local-in-time smooth solutions Strictly convex entropy Generalized Riemann invariants
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An ultra-sensitive dual-mode imaging system using metal-enhanced fluorescence in solid phantoms 被引量:4
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作者 Eran A. Barnoy Dror Fixler +2 位作者 Rachela Popovtzer Tsviya Nayhoz Krishanu Ray 《Nano Research》 SCIE EI CAS CSCD 2015年第12期3912-3921,共10页
In this study, we developed a highly sensitive dual-mode imaging system using gold nanoparticles (GNPs) conjugated to various fluorophores in solid phantoms. The system consists of fluorescence-lifetime imaging micr... In this study, we developed a highly sensitive dual-mode imaging system using gold nanoparticles (GNPs) conjugated to various fluorophores in solid phantoms. The system consists of fluorescence-lifetime imaging microscopy (FLIM) for surface imaging, diffusion reflection (DR) for deep-tissue imaging (up to 1 cm), and metal-enhanced fluorescence (MEF). We detected quenching in the fluorescent intensity (FI) for the conjugation of both gold nanospheres (GNS) and gold nanorods (GNRs) to Fluorescein, which has an excitation peak at a wavelength shorter than the surface plasmon resonance (SPR) of both types of GNPs. Enhanced FI was detected in conjugation to Rhodamine B (RhB) and Sulforhodamine B (SRB), both with excitation peaks in the SPR regions of the GNPs. The enhanced FI was detected both in solution and in solid phantoms by the FLIM measurements. DR measurements detected the presence of GNRs within the solid phantoms by recording the dropped rates of light scattering in wavelengths corresponding to the absorption spectra of the GNRs. With the inclusion of MEF, this promising dual-mode imaging technique enables efficient and sensitive molecular and functional imaging. 展开更多
关键词 gold nanoparticles biomolecular imaging noninvasive detection diffusion reflection fluorescence lifetimeimaging metal-enhanced fluorescence
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A full-duplex optical access system with hybrid 64/16/4QAM-OFDM downlink 被引量:2
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作者 贺超 谭泽富 +5 位作者 邵宇丰 蔡黎 蒲鹤升 朱云乐 黄思斯 刘毓 《Optoelectronics Letters》 EI 2016年第5期361-365,共5页
A full-duplex optical passive access scheme is proposed and verified by simulation, in which hybrid 64/16/4-quadrature amplitude modulation(64/16/4QAM) orthogonal frequency division multiplexing(OFDM) optical signal i... A full-duplex optical passive access scheme is proposed and verified by simulation, in which hybrid 64/16/4-quadrature amplitude modulation(64/16/4QAM) orthogonal frequency division multiplexing(OFDM) optical signal is for downstream transmission and non-return-to-zero(NRZ) optical signal is for upstream transmission. In view of the transmitting and receiving process for downlink optical signal, in-phase/quadrature-phase(I/Q) modulation based on Mach-Zehnder modulator(MZM) and homodyne coherent detection technology are employed, respectively. The simulation results show that the bit error ratio(BER) less than hardware decision forward error correction(HD-FEC) threshold is successfully obtained over transmission path with 20-km-long standard single mode fiber(SSMF) for hybrid downlink modulation OFDM optical signal. In addition, by dividing the system bandwidth into several subchannels consisting of some continuous subcarriers, it is convenient for users to select different channels depending on requirements of communication. 展开更多
关键词 downlink duplex multiplexing quadrature transmitting modulator bandwidth correction transmitter hardware
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Ultra-Low Threshold Optical Bistability and Multi-Stability in Dielecrtric Slab Doped with Semiconductor Quantum Well
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作者 R.Nasehi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第7期129-132,共4页
A scheme for switching of the optical bistability(OB) and multi-stability(OM) in a dielectric slab doped with a three-level ladder-configuration n-doped semiconductor quantum well is simulated. It is shown that the bi... A scheme for switching of the optical bistability(OB) and multi-stability(OM) in a dielectric slab doped with a three-level ladder-configuration n-doped semiconductor quantum well is simulated. It is shown that the bistable behavior of the system in dielectric slab can be controlled via amplitude or relative phase of applied fields. This optical system may provide some new possibilities for test the switching process. 展开更多
关键词 optical bistability quantum well dielectric slab
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