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A transceiver frequency conversion module based on 3D micropackaging technology 被引量:4
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作者 LIU Boyuan WANG Qingping +1 位作者 WU Weiwei YUAN Naichang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期899-907,共9页
The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-... The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-band is realized by combining with the local oscillator and the power control circuit to complete functions such as amplification, filtering and gain. In order to achieve the performance optimization and a high level of integration of the Ku-band monolithic microwave integrated circuits(MMIC) operating chip, the 3 D vertical interconnection micro-assembly technology is used. By stacking solder balls on the printed circuit board(PCB), the technology decreases the volume of the original transceiver to a miniaturized module. The module has a good electromagnetic compatibility through special structure designs. This module has the characteristics of miniaturization, low power consumption and high density, which is suitable for popularization in practical application. 展开更多
关键词 KU-BAND frequency conversion 3D packaging CHIP electromagnetic compatibility
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Quantum frequency down-conversion of single photons at 1552 nm from single InAs quantum dot 被引量:2
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作者 Ben Ma Si-Hang Wei +3 位作者 Ze-Sheng Chen Xiang-Jun Shang Hai-Qiao Ni Zhi-Chuan Niu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期595-599,共5页
Near-infrared single photon sources in telecommunication bands, especially at 1550 nm, are required for long-distance quantum communication. Here a down-conversion quantum interface is implemented, where the single ph... Near-infrared single photon sources in telecommunication bands, especially at 1550 nm, are required for long-distance quantum communication. Here a down-conversion quantum interface is implemented, where the single photons emitted from single In As quantum dot at 864 nm is down converted to 1552 nm by using a fiber-coupled periodically poled lithium niobate(PPLN) waveguide and a 1.95 μmm pump laser, and the frequency conversion efficiency is ~40%. The singlephoton purity of quantum dot emission is preserved during the down-conversion process, i.e., g^((2))(0), only 0.22 at 1552 nm.This present technique advances the Ⅲ-Ⅴ semiconductor quantum dots as a promising platform for long-distance quantum communication. 展开更多
关键词 quantum frequency down-conversion quantum dot telecommunication band single photon
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Noise-free frequency conversion of quantum states
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作者 白云飞 翟淑琴 +1 位作者 郜江瑞 张俊香 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期252-256,共5页
In this paper, the frequency conversion of quantum states based on the intracavity nonlinear interaction is proposed. The fidelity of an input state after frequency conversion is calculated, and it is shown the noise-... In this paper, the frequency conversion of quantum states based on the intracavity nonlinear interaction is proposed. The fidelity of an input state after frequency conversion is calculated, and it is shown the noise-free frequency conversion of a quantum state can be achieved by injecting a strong signal field. The dependences of conversion efficiency on the pump parameter, extra losses and input state amplitude are also analysed. 展开更多
关键词 frequency conversion quantum state FIDELITY
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Quantum frequency up-conversion with a cavity
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作者 白云飞 翟淑琴 +1 位作者 郜江瑞 张俊香 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期237-241,共5页
The quantum state transfer from subharmonic frequency to harmonic frequency based on asymmetrically pumped second harmonic generation in a cavity is investigated theoretically. The performance of noise-free frequency ... The quantum state transfer from subharmonic frequency to harmonic frequency based on asymmetrically pumped second harmonic generation in a cavity is investigated theoretically. The performance of noise-free frequency up- conversion is evaluated by the signal transfer coefficient and the conversion efficiency, in which both the quadrature fluctuation and the average photon number are taken into consideration. It is shown that the quantum property can be preserved during frequency up-conversion via operating the cavity far below the threshold. The dependences of the transfer coefficient and the conversion efficiency on pump parameter, analysing frequency, and cavity extra loss are also discussed. 展开更多
关键词 frequency up-conversion signal transfer coefficient conversion efficiency
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Multiple frequency conversion via atomic spin coherence of storing a light pulse
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作者 王磊 罗梦希 +6 位作者 孙家翔 孙远航 陈怡 魏小刚 康智慧 王海华 高锦岳 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期341-346,共6页
We experimentally demonstrate multiple frequency conversion via atomic spin coherence of storing a light pulse in a doped solid. The essence of this multiple frequency conversion is four-wave mixing based on stored at... We experimentally demonstrate multiple frequency conversion via atomic spin coherence of storing a light pulse in a doped solid. The essence of this multiple frequency conversion is four-wave mixing based on stored atomic spin coherence. Through electromagnetically induced transparency, an input probe pulse is stored into atomic spin coherence by modulating the intensity of the control field. By using two different control fields to interact with the coherently prepared medium, the stored atomic spin coherence can be transformed into three different information channels. Multiple frequency conversion is implemented efficiently by manipulating the spectra of the control fields to scatter atomic spin coherence. This multiple frequency conversion is expected to have potential applications in information processing and communication network. 展开更多
关键词 frequency conversion atomic spin coherence light storage electromagnetically induced trans-parency
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Advanced Power Module Packaging and Integration Structures for High Frequency Power Conversion:From Silicon to GaN 被引量:1
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作者 Fang LUO Lin LIANG +1 位作者 David Huitink Silke Spiesshoefer 《电力电子技术》 CSCD 北大核心 2018年第8期9-18,共10页
The emerging of commercial high-voltage gallium nitride(GaN) power devices provides extraordinary switching performance over silicone devices, which enables high-voltage power conversion switching at megahertz range.S... The emerging of commercial high-voltage gallium nitride(GaN) power devices provides extraordinary switching performance over silicone devices, which enables high-voltage power conversion switching at megahertz range.Such outstanding features also pose strong challenges for device packaging design since the package parasitics can significantly influence the device switching characteristics, and thus can shadow the advantages brought by GaN devices. Designers have been dealing with these challenges brought by high du/dt and high-frequency switching operation even since the silicon(Si) era when fast switching Si MOSFET is first developed and came up with lots of inspiring advanced power module packaging structures to mitigate the problems.This paper presents a review of advanced power module packaging and integration structures that are suitable for high frequency power conversion.The review covers the heritage from the high frequency Si MOSFET packaging to the state-of-the-art for GaN devices. 展开更多
关键词 电力行业 电力技术 电子产品 电力管理
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Decoupled estimation of frequency-dependent IQI and channel for OFDM systems with direct-conversion transceivers 被引量:1
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作者 Yan Liang Rongfang Song +2 位作者 Fei Li Xueyun He Lihua Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期435-441,共7页
The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the t... The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the transmission of the communication signal, the impact of IQI is coupled with channel impulse responses (CIR), which makes the traditional channel estimation schemes ineffective. A decoupled estimation scheme is proposed to separately estimate the frequency-dependent IQI and wireless channel. Firstly, the generalized channel model is built to separate the parameters of IQI and wireless channel. Then an iterative estimation scheme of frequency-dependent IQI is designed at the initial stage of communication. Finally, based on the estimation result of IQI, the least square algorithm is utilized to estimate the channel-related parameters at each time of channel variation. Compared with the joint estimation schemes of IQI and channel, the proposed decoupled estimation scheme requires much lower training overhead at each time of channel variation. Simulation results demonstrate the good estimation performance of the proposed scheme. 展开更多
关键词 direct-conversion transceivers frequency-dependent in-phase and quadrature-phase imbalance (IQI) orthogonal frequency division multiplexing (OFDM) decoupled estimation
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Frequency Up-conversion Luminescence Properties and Mechanism of Tm^(3+) /Er^(3+)/Yb^(3+) Co-doped Oxyfluorogermanate Glasses 被引量:1
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作者 胡曰博 周大利 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期393-397,共5页
Oxyfluoride glasses were developed with composition 60GeO 2 ·10AlF 3 ·25BaF 2 ·(1.95-x)GdF 3 · 3YbF 3 ·0.05TmF 3 ·xErF 3 (x=0.02,0.05,0.08,0.11,0.14,0.17)in mole percent.Intense blue... Oxyfluoride glasses were developed with composition 60GeO 2 ·10AlF 3 ·25BaF 2 ·(1.95-x)GdF 3 · 3YbF 3 ·0.05TmF 3 ·xErF 3 (x=0.02,0.05,0.08,0.11,0.14,0.17)in mole percent.Intense blue(476 nm),green(524 and 546 nm)and red(658 nm)emissions which identified from the 1G 4 →3H 6 transition of Tm3+and the(2H 11/2 ,4S 3/2 )→4I 15/2 ,4F 9/2 →4I 15/2 transitions of Er3+,respectively,were simultaneously observed under 980 nm excitation at room temperature.The results show that multicolor luminescence including white light can be adjustably tuned by changing doping concentrations of Er3+ion or the excitation power.In addition,the energy transfer processes among Tm3+,Er3+and Yb3+ions,and up-conversion mechanisms are discussed. 展开更多
关键词 frequency up-conversion luminescence oxyfluorogermanate glasses Tm3+/Er3+/Yb3+co- doped optical properties energy transfer
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Nonreciprocal Single Photon Frequency Conversion via Chiral Coupling between a V-Type System and a Pair of Waveguides
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作者 Ce Shi Mu-Tian Cheng +4 位作者 Xiao-San Ma Dong Wang Xianshan Huang Bing Wang Jia-Yan Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期34-38,共5页
The single photon frequency conversion is investigated theoretically in the system composed of a V-type system chiral coupling to a pair of waveguides. The single photon scattering amplitudes are obtained using the re... The single photon frequency conversion is investigated theoretically in the system composed of a V-type system chiral coupling to a pair of waveguides. The single photon scattering amplitudes are obtained using the real-space Hamiltonian. The calculated results show that the probability of single photon frequency down-or up-conversion can reach a unit by choosing appropriate parameters in the non-dissipative system with perfect chiral coupling.We present a nonreciprocal single photon beam splitter whose frequency of the output photon is different from that of the input photon. The influences of dissipations and non-perfect chiral coupling on the single frequency conversion are also shown. Our results may be useful in designing quantum devices at the single-photon level. 展开更多
关键词 Nonreciprocal Single Photon frequency conversion via Chiral Coupling between a V-Type System and a Pair of Waveguides
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Scheme for implementing frequency up-conversion between two collective atomic modes
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作者 林丽华 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3890-3892,共3页
This paper presents a scheme for realizing the frequency up-conversion between two collective atomic modes. In the scheme two atomic samples are coupled to a cavity mode. Under the large detuning condition, the two co... This paper presents a scheme for realizing the frequency up-conversion between two collective atomic modes. In the scheme two atomic samples are coupled to a cavity mode. Under the large detuning condition, the two collective atomic modes are coupled via the virtual excitation of the cavity mode and the effective Hamiltonian corresponds to the frequency up-conversion. In the scheme the cavity mode is only virtually excited and thus the process is insensitive to cavity decay. 展开更多
关键词 frequency up-conversion collective atomic mode virtual excitation
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Conversion of Kinetic Energy from Synoptic Scale Disturbance to Low-Frequency Fluctuation over the Yangtze River Valley in the Summers of 1997 and 1999
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作者 李跃凤 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期591-598,共8页
In order to investigate the conversion of kinetic energy from a synoptic scale disturbance (SSD; period≤seven days) to a low-frequency fluctuation (LFF; period〉seven days), the budget equation of the LFF kinetic... In order to investigate the conversion of kinetic energy from a synoptic scale disturbance (SSD; period≤seven days) to a low-frequency fluctuation (LFF; period〉seven days), the budget equation of the LFF kinetic energy is derived. The energy conversion is then calculated and analyzed for the summers of 1997 and 1999. The results show that the energy conversion from the SSD to the LFF is obviously enhanced in the middle and lower troposphere during the heavy rainfall, suggesting this to be one of mechanisms inducing the heavy rainfall, although the local LFF kinetic energy may not be enhanced. 展开更多
关键词 kinetic energy conversion synoptic scale disturbance low-frequency fluctuation heavy rainfall Yangtze River valley
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Time-Frequency Bandwidth Product Estimation of Sinusoidal Non-Linear Chirp Keying Scheme 被引量:1
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作者 Zhiguo Sun Xiaoyan Ning Danyang Tian 《China Communications》 SCIE CSCD 2017年第8期184-194,共11页
Sine Non-linear Chirp Keying(SNCK) is a kind of high-efficient modulation scheme, which provides a potential new beamforming method in communication and radar systems. It has been proved to have advantages in some par... Sine Non-linear Chirp Keying(SNCK) is a kind of high-efficient modulation scheme, which provides a potential new beamforming method in communication and radar systems. It has been proved to have advantages in some parameter estimation issues over conventional modulation schemes. In this paper, a novel transform termed as Discrete Sinusoidal Frequency Modulation transform(DSFMT) is proposed. Then, the DSFMT of SNCK signal is deduced and classified into three types, based on which, the time-bandwidth product is estimated by the proposed algorithm. Simulation results show that the noise has a signifi cant impact on the localization of the peak value and the time-bandwidth product can be estimated by using local ratio values when. 展开更多
关键词 parameter estimation time-bandwidth product sine non-linear chirp keying(SNCK) discrete sinusoidal frequency modulation transform(DSFMT)
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Load Frequency Control of Small Hydropower Plants Using One-Input Fuzzy PI Controller with Linear and Non-Linear Plant Model 被引量:2
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作者 Derek Ajesam Asoh Edwin Nyuysever Mbinkar Albert Nouck Moutlen 《Smart Grid and Renewable Energy》 2022年第1期1-16,共16页
<span style="font-family:Verdana;">This study presents an intelligent approach for load frequency control (LFC) of small hydropower plants (SHPs). The approach which is based on fuzzy logic (FL), takes... <span style="font-family:Verdana;">This study presents an intelligent approach for load frequency control (LFC) of small hydropower plants (SHPs). The approach which is based on fuzzy logic (FL), takes into account the non-linearity of SHPs—something which is not possible using traditional controllers. Most intelligent methods use two-</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">input fuzzy controllers, but because such controllers are expensive, there is </span><span style="font-family:Verdana;">economic interest in the relatively cheaper single-input controllers. A n</span><span style="font-family:Verdana;">on-</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">linear control model based on one-input fuzzy logic PI (FLPI) controller was developed and applied to control the non-linear SHP. Using MATLAB/Si</span><span style="font-family:Verdana;">- </span><span style="font-family:Verdana;">mulink SimScape, the SHP was simulated with linear and non-linear plant models. The performance of the FLPI controller was investigated and compared with that of the conventional PI/PID controller. Results show that the settling time for the FLPI controller is about 8 times shorter;while the overshoot is about 15 times smaller compared to the conventional PI/PID controller. Therefore, the FLPI controller performs better than the conventional PI/PID controller not only in meeting the LFC control objective but also in ensuring increased dynamic stability of SHPs.</span> 展开更多
关键词 Small Hydropower Plant Linear and non-linear Model Load frequency Control non-linear Control Fuzzy Logic Controller Renewable Energy
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Power Allocation for Wireless Powered MIMO Transmissions with Non-Linear RF Energy Conversion Models
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作者 Liqin Shi Liqiang Zhao Kai Liang 《China Communications》 SCIE CSCD 2017年第2期57-64,共8页
We study a radio frequency(RF) wireless energy transfer(WET) enabled multiple input multiple output(MIMO) system. A time slotted transmission pattern is considered. Each slot can be divided into two phases, downlink(D... We study a radio frequency(RF) wireless energy transfer(WET) enabled multiple input multiple output(MIMO) system. A time slotted transmission pattern is considered. Each slot can be divided into two phases, downlink(DL) WET and uplink(UL) wireless information transmission(WIT). Since energy conversion efficiency of the energy harvesting circuits are non.linear, the conventional linear model leads to a mismatch for resource allocation. In this paper, the power allocation algorithm considering the practical non.linear energy harvesting circuits is studied. The optimization problem is formulated to maximize the energy efficiency of system with multiple constraints, i.e., the transmission power, the received power and the minimum harvested energy, which is a non.convex problem. We transform the objective function from fractional form into an equivalent objective function in subtractive form and provide an iterative power allocation algorithm to achieve the optimal solution. Numerical results show that our proposed algorithm with the non.linear RF energy conversion models can achieve much better performance than the algorithm with the conventional linear model. 展开更多
关键词 WET MIMO non-linear energy conversion model energy efficiency power allocation
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ON USING NON-LINEAR CANONICAL CORRELATION ANALYSIS FOR VOICE CONVERSION BASED ON GAUSSIAN MIXTURE MODEL
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作者 Jian Zhihua Yang Zhen 《Journal of Electronics(China)》 2010年第1期1-7,共7页
Voice conversion algorithm aims to provide high level of similarity to the target voice with an acceptable level of quality.The main object of this paper was to build a nonlinear relationship between the parameters fo... Voice conversion algorithm aims to provide high level of similarity to the target voice with an acceptable level of quality.The main object of this paper was to build a nonlinear relationship between the parameters for the acoustical features of source and target speaker using Non-Linear Canonical Correlation Analysis(NLCCA) based on jointed Gaussian mixture model.Speaker indi-viduality transformation was achieved mainly by altering vocal tract characteristics represented by Line Spectral Frequencies(LSF).To obtain the transformed speech which sounded more like the target voices,prosody modification is involved through residual prediction.Both objective and subjective evaluations were conducted.The experimental results demonstrated that our proposed algorithm was effective and outperformed the conventional conversion method utilized by the Minimum Mean Square Error(MMSE) estimation. 展开更多
关键词 Speech processing Voice conversion non-linear Canonical Correlation Analysis(NLCCA) Gaussian Mixture Model(GMM)
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Efficient collinear frequency tripling of femtosecond laser with compensation of group velocity delay 被引量:1
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作者 王燕玲 周绪桂 +1 位作者 吴洪 丁良恩 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4308-4313,共6页
This paper demonstrates an approach that negative uniaxial crystal has a relative anomalous dispersion effect which can compensate group velocity delay, and applies this approach to nonlinear frequency conversion of a... This paper demonstrates an approach that negative uniaxial crystal has a relative anomalous dispersion effect which can compensate group velocity delay, and applies this approach to nonlinear frequency conversion of an ultrafast laser field. High efficiency of the third harmonic generation is experimentally fulfilled by adopting a collinear configuration of doubing-compensation-tripling system. Through finely adjusting the incident angle and optical axis direction of the compensation plate, it obtains ultraviolet (UV) output energy of 0.32 mJ centered at 270 nm with spectral bandwidth of 2 nm when input beam at 800 nm was 70 fs pulse duration and 6 mJ pulse energy which was extracted from Ti:sapphire laser system by a diaphragm, corresponding to an 800-to-270 nm conversion efficiency of 5.3% and a factor-of-l.6 improvement in the third harmonic generation of UV band in comparison with a general conventional configuration. Furthermore, when the full energy of 18 mJ from a Ti:sapphire laser system was used and optimized, the UV emission could reach 0.83 mJ. 展开更多
关键词 nonlinear frequency conversion ultrafast laser SUM-frequency
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Analytic approach to the small-signal frequency response of saturated semiconductor optical amplifiers using multisection model
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作者 周恩波 张新亮 黄德修 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2998-3003,共6页
An analytic solution derived by multisection model to the small-signal frequency response (SSFR) of wavelength conversion based on cross-gain modulation (XGM) in semiconductor optical amplifiers (SOAs) is presen... An analytic solution derived by multisection model to the small-signal frequency response (SSFR) of wavelength conversion based on cross-gain modulation (XGM) in semiconductor optical amplifiers (SOAs) is presented. The result contains details that can affect the characteristics of SSFR significantly more than previous ones. 展开更多
关键词 wavelength conversion cross-gain modulation frequency response semiconductor optical amplifiers
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Quantum frequency doubling based on tripartite entanglement with cavities
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作者 郭娟 魏志峰 张素英 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期62-65,共4页
We analyze the entanglement characteristics of three harmonic modes, which are the output fields from three cav- ities with an input tripartite entangled state at fundamental frequency. The entanglement properties of ... We analyze the entanglement characteristics of three harmonic modes, which are the output fields from three cav- ities with an input tripartite entangled state at fundamental frequency. The entanglement properties of the input beams can be maintained after their frequencies have been up-converted by the process of second harmonic generation. We have calculated the parametric dependences of the correlation spectrum on the initial squeezing factor, the pump power, the trans- naission coefficient, and the normalized analysis frequency of cavity. The numerical results provide references to choose proper experimental parameters for designing the experiment. The frequency conversion of the multipartite entangled state can also be applied to a quantum communication network. 展开更多
关键词 tripartite entanglement frequency conversion quantum communication network
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Influence of laser linewidth on external-cavity frequency doubling efficiency of a 1.56 μm master oscillator fiber power amplifier
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作者 田秀桃 李永民 +1 位作者 刘勤 张宽收 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2324-2327,共4页
By using an external-cavity frequency-doubling master oscillator fiber power amplifier (MOPA), a 700 mW continuous-wave single-frequency laser source at 780 nm is produced. It is shown that the frequency doubling ef... By using an external-cavity frequency-doubling master oscillator fiber power amplifier (MOPA), a 700 mW continuous-wave single-frequency laser source at 780 nm is produced. It is shown that the frequency doubling efficiency is improved when the seed diode laser is optically locked to a resonant frequency of a confocal Fabry-Perot (F-P) cavity. This phenomenon can be attributed to the narrowing of the 1.56 μm laser linewidth and explained by our presented theoretical model. The experimental results are found to be in good agreement with the theoretical predictions. 展开更多
关键词 laser linewidth external-cavity frequency doubling conversion efficiency
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NONLINEAR NATURAL FREQUENCY OF SHALLOW CONICAL SHELLS WITH VARIABLE THICKNESS
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作者 王新志 韩明君 +1 位作者 赵永刚 叶开沅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第3期277-282,共6页
The nonlinear dynamical variation equation and compatible equation of the shallow conical shell with variable thickness are obtained by the theory of nonlinear dynamical variation equation and compatible equation of t... The nonlinear dynamical variation equation and compatible equation of the shallow conical shell with variable thickness are obtained by the theory of nonlinear dynamical variation equation and compatible equation of the circular thin plate with variable thickness. Assuming the thin film tension is composed of two items. The compatible equation is transformed into two independent equations. Selecting the maximum amplitude in the center of the shallow conical shells with variable thickness as the perturbation parameter, the variation equation and the differential equation are transformed into linear expression by theory of perturbation variation method. The nonlinear natural frequency of shallow conical shells with circular bottom and variable thickness under the fixed boundary conditions is solved. In the first approximate equation, the linear natural frequency of shallow conical shells with variable thickness is obtained. In the third approximate equation, the nonlinear natural frequency of it is obtained. The figures of the characteristic curves of the natural frequency varying with stationary loads, large amplitude, and variable thickness coefficient are plotted. A valuable reference is given for dynamic engineering. 展开更多
关键词 variable thickness natural frequency non-linearity perturbation variation method
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