Gao Yu, Pei Yunhe, Xiang Tian, Cheng Liang, Qi Jingbo
State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.
iScience. 2022 Jun 2;25(7):104511. doi: 10.1016/j.isci.2022.104511. eCollection 2022 Jul 15.
In this work, broadband terahertz (THz) wave emissions have been detected from the trigonal layered PtBi on the excitation of the femtosecond laser pulses. Such THz generation is found to arise from the dominated linear photogalvanic effect, which is further discovered to strongly depend on the unique electronic structures of PtBi. Furthermore, an effective nonlinear susceptibility of PtBi is also obtained and is nearly two orders of magnitude larger than that of the traditional nonlinear crystal for THz generation.
在这项工作中，通过飞秒激光脉冲激发，从三角层状PtBi中检测到了宽带太赫兹（THz）波发射。发现这种太赫兹产生源于占主导地位的线性光电流效应，进一步发现该效应强烈依赖于PtBi独特的电子结构。此外，还获得了PtBi的有效非线性极化率，其比传统的太赫兹产生非线性晶体的非线性极化率大近两个数量级。
