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Effects of Correlations Between the Real and Imaginary Parts of Quantum Noise on Intensity Fluctuation for a Single-Mode Laser 总被引:1,自引:0,他引:1 下载免费PDF全文
We study the effects of correlations between the real and imaginary parts of quantum noise on the intensity fluctuation for a single-mode laser. The analytic expressions of the intensity correlation function C(r) and the associated relaxation time Tc in the case of a stable locked phase resulting from the cross-correlation λq between the real and imaginary parts of quantum noise are derived by means of projection operator method. Based on numerical computations it is found that the presence of cross-correlations between the real and imaginary parts of quantum noise causes the intensity fluctuation to increase. A slowing-down phenomenon exists in the sense that Tc increases as a function of |λq|. Thus the decay o[ intensity fluctuation becomes slower. 相似文献
994.
Broad Omnidirectional Reflection Band Forming using the Combination of Fibonacci Quasi-Periodic and Periodic One-Dimensional Photonic Crystals 下载免费PDF全文
By combining two Fibonacci quasi-periodic structures and a periodic structure to form a heterostructure, abroad omnidirectional reflection band is obtained. From the numerical results performed by the transfer matrixmethod, it is found that the reflection bands of the two Fibonacci quasi-periodic sub-structures and the periodicsub-structure can be compensated for each other. This method is expected to be useful in constructing a one-dimensional quasi-periodic photonic crystal structure with a broad omnidirectional reflection band. 相似文献
995.
Direct Measurement of Evanescent Wave Interference with a Scanning Near-field Optical Microscope 下载免费PDF全文
Evanescent wave interference is studied theoretically and experimentally. The interference patterns were directly measured with a scanning near-field optical microscope. The acquired image of the interference pattern is clear and has better contrast than that previously acquired with a photon-scanning tunnelling microscope or lasertrapped particles. The spatial period of the interference fringes is 180 nm, which agrees with the theoretical value. The results indicate that the probe of the scanning near-field optical microscope has a resolution beyond 100nm. The relation between the evanescent field intensity and the distance is also measured. When the separation between the probe and the interface is up to 18Ohm, the intensity can decrease to 1/e of the maximum. 相似文献
996.
光子扫描隧道显微镜球形样品二维近场强度分析 总被引:6,自引:2,他引:4
采用时域有限差分方法计算全内反射和光子扫描隧道显微镜系统。光子扫描隧道显微镜的基本工作原理是隐失波的产生和探测,当入射光在两种介质的分界面上发生全内反射,并在界面处产生非辐射的电磁波——隐失波时,采取对两界面入射光进行分别设置的方法即“三波法”设置入射激励元。分别计算一个球和两个球形样品的近场分布,并计算散射小球为探针,一个球为样品的扫描图像。结果表明:采用二维时域有限差分方法计算能较直观地显示样品表面的近场分布。表明时域有限差分方法在光子扫描隧道显微镜理论研究中具有很大潜力。 相似文献
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Large Bandwidth Optical Limiting by Kerr Medium Doped One-Dimensional Coupled Cavity Optical Waveguides 总被引:2,自引:0,他引:2 下载免费PDF全文
We present a new method to realize large bandwidth optical limiting using Kerr nonlinearity doped one-dimensional coupled cavity optical waveguides (CCOWs). When the incident intensity is weak, the structure is a perfect CCOW that supports a high transmission band. When the intensity is increased, the Kerr effects change the refractive index of the Kerr cavity which results in a large decrease of transmission coefficients in the whole band. We numerically analyse the limiter using the nonlinear transfer matrix method and nonlinear finite difference in time domain method. Optical limiting effects are observed in the whole transmission band, and optimization methods are also discussed. 相似文献
1000.
全带隙光子晶体中依赖原子位置的衰减动力学性质 总被引:2,自引:0,他引:2
介绍一个二能级原子在全带隙光子晶体带边附近的衰减动力学行为 .发现原子位置的变化会根本地改变激发原子的衰减特性 :由于光场和原子之间局域耦合强度的巨大差异 ,导致Weisskopf Wigner和非Weisskopf Wigner衰减现象 .预言可通过控制原子的位置来实现人工剪裁荧光光谱 相似文献