光学学报, 2010, 30 (5): 1434, 网络出版: 2010-05-11
对交叉偏振波滤波器能量转化效率和频谱相位的研究
Study on the Energy Conversion Efficiency and Spectral Phase of Cross-Polarized Wave Generation Filter
非线性光学 交叉偏振波 相位调制 三阶频谱相位 nonlinear optics cross-polarized wave phase modulation third-order spectral phase
摘要
交叉偏振波(XPW)滤波是一种简单灵活的非线性滤波技术,可以极大地提高超短超强飞秒激光脉冲信噪比。介绍了XPW滤波器原理,通过数值模拟得到以下结论:输入光偏振方向与晶体的[100]轴的夹角β、相位调制(PM)、注入光强和晶体长度以及不同的空间光束分布都会影响XPW的能量转化效率。其中PM是造成能量转化过早饱和,导致最大转化效率降低的主要原因。同时注入光的初始二阶和三阶频谱相位会导致XPW脉冲形状畸变,谱宽窄化,中心频移,能量转化效率减小。为 XPW非线性滤波装置能够有效地提高超强超短脉冲的信噪比提供了理论依据。
Abstract
Cross-polarized wave (XPW) generation is a simple and flexible nonlinear filter for the contrast improvement of ultra-intense femtosecond laser pulse,which could enhance signal-to-noise ratio(SNR) efficiently. The principle of XPW filter is introduced briefly. The results from numerical simulation indicate that the XPW energy conversion efficiency is determined by the angle β between the input polarization direction and its [100] axis,phase modulation (PM),input intensity,crystal length and spatial shape. Among them,PM is the main cause of shorting saturation length and decreasing maximum conversion efficiency. It also reveals that initial quadratic and third-order spectral phase induced XPW pulse shape distortion,spectrum narrowing,central spectral shift of the center and efficiency decline,which provides the theoretical basis for XPW nonlinear filter to enhance ultra-intense and ultra-short pulse effectively.
潘雪, 王艳海, 王江峰, 姜有恩, 李学春. 对交叉偏振波滤波器能量转化效率和频谱相位的研究[J]. 光学学报, 2010, 30(5): 1434. Pan Xue, Wang Yanhai, Wang Jiangfeng, Jiang Youen, Li Xuechun. Study on the Energy Conversion Efficiency and Spectral Phase of Cross-Polarized Wave Generation Filter[J]. Acta Optica Sinica, 2010, 30(5): 1434.