Influence of Two-Photon Absorption Anisotropy on Terahertz Emission Through Optical Rectification in Zinc-Blende Crystals

被引:0
作者
Federico Sanjuan
Gwenaël Gaborit
Jean-Louis Coutaz
机构
[1] Université Savoie-Mont-Blanc,IMEP
[2] Kapteos,LAHC, UMR C.N.R.S 5130
来源
Journal of Infrared, Millimeter, and Terahertz Waves | 2018年 / 39卷
关键词
Nonlinear optics; Anisotropic optical materials; Spectroscopy; Terahertz; Ultrafast lasers;
D O I
暂无
中图分类号
学科分类号
摘要
We report for the first time on the observation of an angular anisotropy of the THz signal generated by optical rectification in a < 111 > ZnTe crystal. This cubic (zinc-blende) crystal in the < 111 > orientation exhibits both transverse isotropy for optical effects involving the linear χ(1) and nonlinear χ(2) susceptibilities. Thus, the observed anisotropy can only be related to χ(3) effect, namely two-photon absorption, which leads to the photo-generation of free carriers that absorb the generated THz signal. Two-photon absorption in zinc-blende crystals is known to be due to a spin-orbit interaction between the valence and higher-conduction bands. We perform a couple of measurements that confirm our hypothesis, as well as we fit the recorded data with a simple model. This two-photon absorption effect makes difficult an efficient generation, through optical rectification in < 111 > zinc-blende crystals, of THz beams of any given polarization state by only monitoring the laser pump polarization.
引用
收藏
页码:378 / 386
页数:8
相关论文
empty
未找到相关数据