摘要
Yuika等人利用偏振CARS技术可以准确地确定分子的拉曼退偏比.其方法是,首先对不同检偏角Фd所对应CARS谱峰的频率分布进行数学模拟,然后由所得系数随检偏角Фd的变化求得使CARS信号中共振项消失的偏振角Фd0,最后由消失条件ρ=-1/(tanθtanФ0d)求出退偏比ρ,θ为产生CARS光的Pump光与Stokes光偏振方向的夹角.本文提出的数据处理方法,即交点法.同Yuika等人处理数据的方法相比,交点法毋需关于谱峰频率分布的知识,做法也更为简便.
The Raman depolarization ratio ρ can be determined accurately by polarization-resolved coherent anti-stokes scattering （CARS） technique （J. Raman Spectrosc., 2000, 31：725 ）. The polarized CARS spectra are recorded at a series of polarization angles φd, and simulated by a Lorentz bandshape to obtain signal amplitude Hr of the resonant part. From the dependence of HR on polarization angle φd, the angle φd^0 corresponding to HR = 0 can be determined. So the Raman depolarization ratio can be obtained from the relationship ρ = - 1/（tanθtanφd^0 ）, where 0 is the polarization angle between Pump beam and Stokes beam. In this report, we introduce another method to process the data from polarized CARS spectrum, namely the method of intersecting point. Compared with the original method, our method needs not any knowledge of frequency distribution of the CARS spectrum, and is simpler.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第5期2699-2703,共5页
Acta Physica Sinica
基金
国家自然科学基金(20533070)资助的课题~~
关键词
CARS
拉曼退偏比
CARS, Raman depolarization ratio
