Terahertz generation and detection of LT-GaAs thin film photoconductive antennas excited by lasers of different wavelengths  

作　　者：Xin Liu Qing-Hao Meng Jing Ding Zhi-Chen Bai Jia-Hui Wang Cong Zhang Bo Su Cun-Lin Zhang 刘欣;孟庆昊;丁晶;白志晨;王佳慧;张聪;苏波;张存林(Beijing Advanced Innovation Center for Imaging Theory and Technology,Beijing Key Laboratory for Terahertz Spectroscopy and Imaging;Key Laboratory of Terahertz Optoelectronics,Ministry of Education,Department of Physics,Capital Normal University,Beijing 100048,China)

机构地区：[1]Beijing Advanced Innovation Center for Imaging Theory and Technology,Beijing Key Laboratory for Terahertz Spectroscopy and Imaging [2]Key Laboratory of Terahertz Optoelectronics,Ministry of Education,Department of Physics,Capital Normal University,Beijing 100048,China

出　　处：《Chinese Physics B》2022年第2期677-680,共4页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.61575131)。

摘　　要：A new method of generating and detecting terahertz waves is proposed.Low-temperature-grown gallium arsenide(LT-Ga As)thin films are prepared by etching a sacrificial layer(Al As)in a four-layer epitaxial structure constituted with LT-Ga As,Al As,Ga As,and semi-insulating gallium arsenide(SI-Ga As).The thin films are then transferred to clean silicon for fabricating the LT-Ga As thin film antennas.The quality and transmission characteristics of the films are analyzed by an800-nm asynchronous ultrafast time domain spectroscopy system,and the degree of bonding between the film and silicon wafer is determined.Two LT-Ga As thin film antennas for generating and detecting the terahertz waves are tested with a1550-nm femtosecond laser.The terahertz signal is successfully detected,proving the feasibility of this home-made LTGa As photoconductive antennas.This work lays a foundation for studying the mechanism of terahertz wave generation in Ga As photoconductive antennas below the semiconductor band gap.

关 键 词：TERAHERTZ low-temperature-grown GaAs photoconductive antenna 1550-nm laser 

分 类 号：TN820[电子电信—信息与通信工程] O441.4[理学—电磁学] O484[理学—物理]