Pancharatnam's Phase for Polarized Light

Abstract

This paper presents a classical theoretical analysis of the geometric phase arising in a cyclic change of the polarization state of light beams. We compare the results obtained this way with the quantum mechanical analysis.     

Phase Properties of Elliptically Polarized Light Propagating in a Kerr Medium

Abstract

Phase properties of elliptically polarized light propagating through a nonlinear Kerr medium are considered within the framework of the Pegg-Barnett Hermitian phase formalism. The joint phase probability distribution function for the phases of two orthogonal modes describing elliptical polarization of the field is calculated and its evolution discussed and illustrated graphically. The marginal phase probability distribution for the individual phases are also calculated and discussed. Analytical formulae for phase expectation values and variances are derived for the individual phases as well as for the phase difference. It is shown that in the course of propagation the correlation between the phases of the two modes builds up. This correlation is responsible for lowering phase difference variance. The expressions for the sine and cosine functions and their variances of the individual phases as well as the phase difference are obtained and discussed. The effect of randomization of individual phases and the phase difference, which is a purely quantum effect, is shown to appear during propagation. The relation between phase randomization and degradation of the degree of polarization of the light is established.     

Approximate Formulae for Mixed Modulated Coherent and Partially Polarized Chaotic Light

Exact and approximate formulae are obtained for the counting statistics of mixed cosine-modulated coherent and partially polarized chaotic light, particularly with Lorentzian spectrum, for one-photon as well as multiphoton absorption. They are numerically analysed and the accuracy of the approximate formulae is discussed. As a special case chaotic light is investigated. A closer relation to recent papers is outlined.     

A Measurement Method for Birefringent Plate using Elliptically Polarized Light

Abstract:  The principal axis ψ and total relative phase retardation ρ _tot of a birefringent plate are obtained automatically using an elliptically polarized incident light source and a phase unwrapping technique. The technique overcomes the error associated with the quarter-wave plate by making use of incident light of different wavelengths, and the unwrapping technique allows ψ and ρ _tot to be determined using an arctangent function without interpolation or construction of a calibration table. The proposed method is validated analytically and experimentally for a circular disk under diametral compressive load.     

High-precision Tunable Retardation Plate for Use with Visible and Ultra-violet Polarized Light

A variable retardation plate suitable for polarizing optics in the visible and ultra-violet has been developed. It is based on the photoelastic effect induced by lateral compression of a rectangular plate of fused silica. A special pressure frame employing hydraulic pressure gives very even compression, and the stress pattern induced is uniform to within 1 per cent over most of the plate area. A pneumatic ballast system has also been developed to stabilize the pressure, which maintains the retardation constant to within ½ per cent over a period of hours. Possible applications of the retardation plate in optical instrumentation and in the accurate measurement of pressure are discussed.     

基于正交偏振光的瓦斯浓度传感器研究

介绍了瓦斯浓度传感器系统的基本原理,提出了基于正交偏振光的差分吸收式瓦斯浓度检测模型,建立了瓦斯浓度传感器的数学模型,设计了传感器系统结构以及光路和气室结构,并对传感器进行了实验研究.传感器系统利用起偏器将两束不同波长的单色光转变为正交偏振光,然后让这两束正交偏振光同时通过检测气室,最后用渥拉斯顿棱镜将两束单色光分开,...     

超微细光刻中偏振光成像研究

在大数值孔径、短波长的投影光学光刻系统中,对S偏振光、P偏振光和非偏振光在硅片上的成像进行了研究,发现S偏振光成像具有最高的光强对数斜率值和最大的对比度;模拟了S偏振光通过掩模的电场分布机理,结果表明,可以通过调制照明光的偏振性来提高成像对比度和分辨力。     

关于圆偏振光在3D立体影像显示中的应用——对《3D立体影像显示方法丛谈》的补充诠释

本文阐述了圆偏振光的生成机理,旋转方向的控制方法与相关切换装置,圆偏振眼镜的结构以及圆偏振光应用于3D立体影像显示的优越性。     

浅谈偏振光照相在现代刑事技术中的应用

偏振光照相技术在现代刑事科学技术领域运用广泛,发挥着重要的作用。本文阐述了偏振光照相的原理、操作的一般方法以及在指纹等痕迹物证检验、法医检验、微量物证检验中的应用。     

球形粒子对平面偏振光散射的数值计算与分析

论文在Mie理论基础上,给出了球形粒子对平面偏振光的散射强度和散射系数公式,利用连分式递推算法进行了编程计算,重点对1.06μm激光的模拟结果进行了分析.从得到的散射图像可以看出,散射强度角分布与散射粒子尺度有密切关系,随着粒子尺度的逐渐增大,散射光强主要集中到前、后向散射方向,集中的角度越来越窄,模拟结果明显出现了散射强度最弱的极值角,且该极值角随粒径的增大而增大,最后逼近90°方向.散射强度角分布与波长有关,当它们在同一数量级时达到最大值,与散射粒子折射率无关.该递推算法因为每一步计算都是独立的,与前后项的准确性没有关系,不存在不稳定、发散等情况,能够计算粒径参数范围从10-4开始,对上限不受任何限制.     

Interaction of Counter-propagating Elliptically Polarized Light Waves in Isotropic Nonlinear Media

Abstract

The nonlinear interaction of elliptically polarized counter-propagating waves in an isotropic transparent medium is analysed. Self-induced changes in the polarization of the counter-propagating light waves, are described. Using these results, a new type of modulator giving self-induced rotation of the polarization ellipse (SIRPE) is studied. The transmission of counter-propagating waves in the SIRPE modulator is shown to exhibit saturation with increase in light intensity and to be a multiple-valued function of the light intensity.     

Adiabatic Phase Diagram of a Degenerate Fermi Gas with a Feshbach Resonance

We determine the adiabatic phase diagram of a resonantly-coupled system of Fermi atoms and Bose molecules confined in a harmonic trap by using the local density approximation. The key idea of our work is conservation of entropy through the adiabatic process. We also calculate the molecular conversion efficiency as a function of the initial temperature. Our work helps to understand recent experiments on the BCS-BEC crossover, in terms of the initial temperature measured before a sweep of the magnetic field.     

Measurements of Heat Capacity and Enthalpy of Phase Change Materials by Adiabatic Scanning Calorimetry

Phase change materials (PCMs) are substances exhibiting phase transitions with large latent heats that can be used as thermal storage materials with a large energy storage capacity in a relatively narrow temperature range. In many practical applications the solid–liquid phase change is used. For applications accurate knowledge of different thermal parameters has to be available. In particular, the temperature dependence of the enthalpy around the phase transition has to be known with good accuracy. Usually, the phase transitions of PCMs are investigated with differential scanning calorimetry (DSC) at fast dynamic scanning rates resulting in the effective heat capacity from which the (total) heat of transition can be determined. Here we present adiabatic scanning calorimetry (ASC) as an alternative approach to arrive simultaneously at the equilibrium enthalpy curve and at the heat capacity. The applicability of ASC is illustrated with measurements on paraffin-based PCMs and on a salt hydrate PCM.