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反射相移色散对OCS灵敏度影响的理论研究 总被引:5,自引:3,他引:2
以琼斯矩阵为数学工具,利用理论分析和计算机仿真的方法研究了单层保偏反射膜反射相移的色散特性及其对光学电流传感器灵敏度的影响.在光学电流传感器系统中,光源的驱动电流与环境温度改变,都会造成光源峰值波长移动.由于反射膜上产生的反射相移的色散特性,会使光学电流传感器的灵敏度随光源波长的变化而改变.研究结果表明,反射相移的色散特性会对输出曲线的尺度因子产生明显的影响.因此,光源的恒温控制与光源驱动电流的恒流控制是必要的. 本研究结果可为光学电流传感器的研究设计人员提供有用的参考. 相似文献
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在单层保偏膜式光学玻璃电流传感系统中,费尔德(Verdet)常数、线性双折射和反射相移都是光波长的函数即存在色散特性,因此在采用宽带光源时系统中会产生波长积累效应。先给出了三者的色散特性公式,再对其波长积累效应进行理论分析和计算机仿真。研究结果表明,在所考虑的线性双折射和反射相移的量值范围内,波长积累效应对光学玻璃电流传感系统影响甚微,用单色光模型处理宽带系统的做法是合理的与可行的;光源谱宽变化对系统输出的影响小于0.025%,在考虑三者的联合影响时,Verdet常数色散的影响占主导地位,而且整体上系统输出随光源谱宽的增加而有微弱增加。 相似文献
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以琼斯矩阵为数学工具,利用理论分析和计算机仿真的方法研究了块状玻璃光学电流互感器传感头的色散特性对系统灵敏度的影响,并进行了实验验证.在光学电流互感器系统中,光源的驱动电流与环境温度改变,都会造成光源峰值波长移动.而在传感头中主要是由单层保偏反射膜的反射相移、光学玻璃的Verdet常数以及光学玻璃内的线性双折射这三个因素的色散特性,使得光学电流互感器的灵敏度随光源波长的变化而改变.研究结果表明,这种色散特性会对输出曲线的尺度因子产生明显的影响.因此,光源的恒温控制与光源驱动电流的恒流控制是必要的.本研究结果可为光学电流互感器的研究设计人员提供有用的参考. 相似文献
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应用特征矩阵法研究了非均匀渐变界面Al0.9Ga0.1As/AlyGa1-yAs/GaAs/AlxGa1-xAs DBR的光学特性.建立了非均匀渐变界面AlyGa1-yAs的折射率模型,并得到了渐变界面特征矩阵的解析解,通过特征矩阵法分别计算了突变GaAs/Al0.9Ga0.1As DBR和渐变DBR的反射谱和反射相移,分析了非均匀渐变层对DBR光学特性的影响,对渐变DBR,需要在DBR前面再增加一定厚度的非均匀渐变相位匹配层才能使整个DBR满足中心波长相位匹配条件,并通过光学厚度近似方法求出相位匹配层厚度.
关键词:
DBR
反射谱
反射相移
特征矩阵法 相似文献
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提出了基于旋转λ/2波片无色散相移器的理论模型,和实施该相移器功能的全场光学相干层析成像(Optical coherence tomography,OCT)系统,为实现快速、高分辨光学相干层析成像提供了一种有效方法。该相移器能在宽光谱范围内无色散地获得八倍于λ/2波片旋转角的相移量,避免了利用单色光相移算法提取信号时存在的系统误差。针对修正Carré算法和三步相移算法所要求的不同相移量,在240 nm波长范围内,对相移器的性能进行了数值分析。结果表明,在给定光谱范围内,相移量越大,相移误差的绝对值也越大,幅值比变化范围也越大。用于实施无色散相移器功能的全场光学相干层析成像系统结构,与现有结构相比,具有一些有益的特点。 相似文献
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Nonlinear intrachannel interactions responsible for timing shifts in a transmission system with strong periodic dispersion management are investigated. Formulas describing the evolution of the timing shift are obtained for general bit patterns. When average dispersion is negligible, the timing shift is shown to grow linearly in distance in a system with loss and lumped amplification, whereas in a lossless system the timing shift is sufficiently small at every chirp-free point. The analysis agrees with direct numerical simulations. 相似文献
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Ahmed Salah A. S. Abdel-Rady Abdel-Nasser A. Osman Samia S. A. Hassan 《Journal of Russian Laser Research》2018,39(1):28-36
We present a two-level atomic Bose–Einstein condensate (BEC) with dispersion, which is coupled to a high-finesse optical cavity. We call this model the extended Jaynes–Cummings–Dicke (JC-Dicke) model and introduce an effective Hamiltonian for this system. From the direct product of Heisenberg–Weyl (HW) coherent states for the field and U(2) coherent states for the matter, we obtain the potential energy surface of the system. Within the framework of the mean-field approach, we evaluate the variational energy as the expectation value of the Hamiltonian for the considered state. We investigate numerically the quantum phase transition and the Berry phase for this system. We find the influence of the atom–atom interactions on the quantum phase transition point and obtain a new phase transition occurring when the microwave amplitude changes. Furthermore, we observe that the coherent atoms not only shift the phase transition point but also affect the macroscopic excitations in the superradiant phase. 相似文献
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Measurements of dc conductivity and dielectric constant show that deuteration causes an upward shift of the high temperature phase transition point from 186.5 to 191°C and a downward shift of the low temperature transition point from 10 to -1.5°C in LiNH4SO4. Mechanisms of phase transitions and of electrical transport in the crystal are discussed. 相似文献
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圆形双芯微结构色散补偿光纤的色散特性分析 总被引:1,自引:0,他引:1
提出了一种圆形双芯微结构光纤,用频域有限差分法(FDFD),并对其色散特性进行了分析,并与前人提出的六边形双芯微结构色散补偿光纤进行了比较。结果表明:当圆形双芯微结构色散补偿光纤的高折射率区半径保持不变时,改变沿水平直径方向相邻空气洞中心点间的距离和空气洞的直径,能够控制有效模折射率的转折点,并在该处产生较大的负色散。由于圆形双芯微结构色散补偿光纤比六边形双芯微结构色散补偿光纤的有效模折射率对参数变化较为敏感,故前者更易于精确地控制转折点,达到色散补偿的目的。 相似文献
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E. G. Brutan G. T. Voronina N. I. Dvorovenko A. A. Kolesnikova A. V. Sechkarev 《Russian Physics Journal》1967,10(2):80-80
Raman spectra are reported for 32 compounds in the vapor and liquid states at various temperatures, and also in the crystalline state. It is found that the frequencies of the C-H modes show a shift on phase transition; the magnitude and direction of this are not dependent on the polarity. The effect is assumed to be due to London dispersion forces. 相似文献
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Mahmoud A. Khaskan 《Optics Communications》1973,8(3):220-221
The work reported here concerns concentric rings whose centre serves as a fiduciary point and a compensation method is applicable. The applications to dispersion, refraction, length or phase shift measurements are pointed out. 相似文献
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The dispersion relation of the intersurfacedband plasmon, i.e., collective excitation of the surface electrons of the clean or adsorbed surfaces, is investigated by the self-consistent field approach. The dispersion is predicted to start with the linear term in the wave number parallel to the surface, which will be helpful to distinguish the plasmon from the individual excitations. The sign of the dispersion and the depolarization shift depend on the polarization of the interband transition. The contribution of the plasmon to the electron energy loss cross section is given. 相似文献