光学学报, 1986, 6 (3): 212, 网络出版: 2011-09-16  

偏振调制双光子光谱理论计算

Theoretical calculation of polarization modulated two-photon spectroscopy
作者单位
华东师范大学物理系
摘要
本文从密度矩阵运动方程出发,推导出当各种不同偏振调制激光场与三能级粒子系统相互作用时,同核双原子分(具近共振中间能波)单重电子态之间的双光子跃迁所产生的荧光信号强度和线型.对比偏振调制的与光子强调制的信号强度和线型时,表明:偏振调制双光子光谱(PMTPS)不仅能消除由吸收同一光束的同向双光子所产生的多普勒加宽背景,极大地提高光谱分辨率;而且不同电子态之间跃迁的O、P、Q、R、S支谱线强度与激光偏振状态有关,可借以标识分子的高激发电子终态和转动能级,有选择地简化复杂的分子光谱.可以预期,PMTPS是研究分子光谱和高分辨率激光光谱极有用的一种技术.
Abstract
Based on the density matrix equations with 3-j symbol expression, we calculated the intensities and lineshapes of fluoresence signals for two-photon transitions between homonuclear diatomio molecular singlet electronic states, which have a near-resonant intermediate enhancing level. Calculations were made for interactions between a variety of polarization modulated laser fields with three level systems. Signals obtained by the phase-sensitive detection method showed that either the circular polarization modulated method (LPMTPS) could be used to eliminate the Doppler broadening background caused by the adsorption of two photons from one beam. In addition these methods could be used to identify the specific branches of the two photon lines from their ixregnler spectral strnotirres without the need of knowing the upper ΙθτθΙ constants. Signal ratios of eqnal-frequenoy two-photon transitions under circular polarization modulation condition to those with linear polarization modulation wore listed for all the branches with AJ =±2,±1 and 0. Differences of the results might be orders of magnitude fox a resonable large J value. On the other hand signal ratios of two-photon branches in the intensity modulated circulax polarization laser field to those in linear polarization fields (shown in another list) are all in the same order. Furthermore, a table is presented to show the relative signal intensities of unequal-frequency polarization modulated two-photon transitions between various eleotronio states. It might be useful for determining intermediate or upper electronic states of a resolved two-photon absorption line. PMTPS is thus expected to be a usefal method for ruoleonlax spectroscopy or highresolution laser spectroscopy.

蔡继光, 夏慧荣, 郑一善. 偏振调制双光子光谱理论计算[J]. 光学学报, 1986, 6(3): 212. CAI JIGUANG, XIA HUIRONG, CHENG ISHAN. Theoretical calculation of polarization modulated two-photon spectroscopy[J]. Acta Optica Sinica, 1986, 6(3): 212.

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!