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491.
Hong-yi Fan Yue Fan 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(2):233-238
Starting from the Einstein-Podolsky-Rosen entangled state representations of continuous variables we derive a new formulation
of complex fractional Fourier transformation (CFFT). We find that two-variable Hermite polynomials are just the eigenmodes
of the CFFT. In this way the CFFT is linked to the appropriate operator transformation between two kinds of entangled states
in the context of quantum mechanics. In so doing, the CFFT of quantum mechanical wave functions can be derived more directly
and concisely.
Received 21 February 2002 / Received in final form 1st June 2002 Published online 24 September 2002
RID="*"
ID="*"Work supported by National Natural Science Foundation of China under grant 10175057 and the President Foundation of
Chinese Academy of Science.
RID="a"
ID="a"e-mail: fhym@ustc.edu.cn 相似文献
492.
调制对磁共振谱的线宽,线形及幅值的影响 总被引:2,自引:2,他引:0
用付里叶分析方法从理论上分析计算了磁场调制对谱线(单一或重迭的)的线宽、线形及幅值的影响,并将理论计算结果与激光磁共振谱的调制效应的实验结果作了比较,两者符合得很好。据此作者提出了对于采用调制相检技术的磁共振谱技术普遍适用的选择调制参数的方法、步骤和原则。 相似文献
493.
This paper describes the evolution history of the Photonic Network, and highlights our recent research activities on Photonic Multi-Protocol Label Switching and ultra-wideband transmission technologies. The Photonic Multi-protocol Label Switching technology, one of the hottest research area, can be extended to provide optical burst-by-burst data switching. The novel optical modulation technology and multi-optical carrier generation technology based on Supercontinuum light sources will be the key to create bandwidth abundant ultra-large capacity wavelength-division multiplexing (WDM) transmission. 相似文献
494.
Summary A numerical procedure, partly based on the Monte Carlo method, is employed to examine the effect of inhomogeneity of a turbid
medium on the Modulation Transfer Function of an optical system. The results, both for a particulate of small size and of
size comparable with wavelength, show a general effect of the ?shower curtain? type. 相似文献
495.
M. Li S. Zhao G. Q. Li K. Yang D. Li J. Wang J. An 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(1):181-186
A diode-pumped passively Q-switched mode-locked (QML)
intracavity frequency doubled c-cut Nd:GdVO4/KTP green laser with a
LT-GaAs saturable absorber is presented. More than 90% modulation depth
for the mode-locked green pulses has been achieved. Using the hyperbolic
secant function methods, a developed rate equation model for Q-switched and
mode-locked lasers considering the Gaussian spatial distribution of the
intracavity photon intensity, the influences of continuous pump rate, the
upper state lifetime of the active medium, and the excited-state lifetime of
the saturable absorber, was proposed. With this developed model, the
theoretical results are in good agreement with the experimental results and
the width of the mode-locked green pulse was estimated to be about 380 ps. 相似文献
496.
用重复旋转涂膜法制备了乙基红(ER)偶氮染料与聚甲基丙烯酸甲酯(PMMA)掺杂聚合物薄膜和乙基橙(EO)与聚乙烯醇(PVA)掺杂聚合物薄膜.测量了两种聚合物薄膜样品全光开关特性,比较分析了薄膜样品的掺杂浓度和溶剂对全光开关效应的影响,实验结果表明:增加掺杂浓度和溶剂,极性薄膜样品的全光开关效应增强且开关的本底信号增大,但对开关的响应速度影响很小;选择合适的掺杂浓度和强极性溶剂,在室温和几个mW的弱功率控制光条件下聚合物薄膜具有毫秒级开关响应时间和40%以上的开关调制深度,最大的调制深度达72%以上. 相似文献
497.
498.
The transmission of 40 Gb/s wavelength multiplexed channels under vestigial single side band modulation format is transmitted over long haul optically amplified fiber systems. Bit-error-rate (BER) of 10−12 or better can be achieved across all channels. Optical filters are designed with asymmetric roll-off bands. Simulations of the transmission performance, BER versus receiver sensitivity are demonstrated with wavelength channel spacing of 20–40 GHz. An optical filter, whose passband is 28 GHz and 20 dB cut-off band, performs best for 40 Gb/s bit rate due to optimum filtering and minimum noise contribution. Furthermore the single-sideband property of VSB format can assist linear equalization by electronic processing. The transmission performance is accurately evaluated based on the eye opening using a fast statistical method based on an equivalent Gaussian probability density distribution (pdf) which is derived from multiple peaks pdf of distorted eye diagram. 相似文献
499.
Jiu-sheng Li 《Optik》2008,119(1):19-22
A novel optical modulator using SiO2 waveguides on a silicon substrate is proposed. The modulator is analyzed and designed with the finite element method. The numerical results have shown that an optimally designed modulator can give a broad bandwidth, good impedance match, and low cost. The proposed modulator can be fabricated easily using Si-based very large-scale integrated technology, and it is very suitable for opto-electronic integrated circuits. 相似文献
500.