Broadband terahertz radiation from a biased two-dimensional electron gas in an AlGaN/GaN heterostructure  

作　　者：郑中信 孙建东 周宇 张志鹏 秦华 

机构地区：[1]Key Laboratory of Nanodevices and Applications,Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Journal of Semiconductors》2015年第10期55-59,共5页半导体学报（英文版）

基　　金：Project supported by the National Basic Research Program of China(No.G2009CB929303);the National Natural Science Foundation of China(No.61271157);the China Postdoctoral Science Foundation(No.2014M551678);the Jiangsu Planned Projects for Postdoctoral Research Funds(No.1301054B)

摘　　要：The broadband terahertz （THz） emission from drifting two-dimensional electron gas （2DEG） in an AI- GaN/GaN heterostructure at 6 K is reported. The devices are designed as THz plasmon emitters according to the Smith-Purcell effect and the ＇shallow water＇ plasma instability mechanism in 2DEG. Plasmon excitation is excluded since no signature of electron-density dependent plasmon mode is observed. Instead, the observed THz emission is found to come from the heated lattice and/or the hot electrons. Simulated emission spectra of hot electrons taking into account the THz absorption in air and Fabry-Pérot interference agree well with the experiment. It is confirmed that a blackbody-like THz emission will inevitably be encountered in similar devices driven by a strong in-plane electric field. A conclusion is drawn that a more elaborate device design is required to achieve efficient plasmon excitation and THz emission.The broadband terahertz （THz） emission from drifting two-dimensional electron gas （2DEG） in an AI- GaN/GaN heterostructure at 6 K is reported. The devices are designed as THz plasmon emitters according to the Smith-Purcell effect and the ＇shallow water＇ plasma instability mechanism in 2DEG. Plasmon excitation is excluded since no signature of electron-density dependent plasmon mode is observed. Instead, the observed THz emission is found to come from the heated lattice and/or the hot electrons. Simulated emission spectra of hot electrons taking into account the THz absorption in air and Fabry-Pérot interference agree well with the experiment. It is confirmed that a blackbody-like THz emission will inevitably be encountered in similar devices driven by a strong in-plane electric field. A conclusion is drawn that a more elaborate device design is required to achieve efficient plasmon excitation and THz emission.

关 键 词：two-dimensional electron gas hot electron blackbody radiation PLASMON Fabry-Pérot cavity 

分 类 号：O441[理学—电磁学]