Eur. Phys. J. B 29, 553-559 (2002)
https://doi.org/10.1140/epjb/e2002-00339-x

Balance-equation approach to impact ionization induced by an intense terahertz radiation: Application to InAs/AlSb heterojunctions

¹ State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, PR China
² Department of Physics, Shanghai Jiaotong University, 1954 Huashan Road, Shanghai, 200030, PR China, and State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, PR China

Corresponding author: ^a jccao8@hotmail.com

Received: 24 May 2002
Revised: 26 August 2002
Published online: 31 October 2002

Abstract

We have extended the balance equations to account for conduction-valence interband impact ionization (II) process induced by an intense terahertz (THz) electromagnetic irradiation in semiconductors, and applied them to study the II effect on electron transport and electron-hole pair generation-recombination rate in THz-driven InAs/AlSb heterojunctions (HJ). As many as needed multiphoton channels are self-consistently taken into account for yielding a given accuracy. The time evolution of transport state including THz-radiation-induced II process are monitored in details by an extensive time-dependent analysis. Two different physical stages, the quasi-steady state and the complete steady-state, are clearly identified from the present calculations. Intersubband electron transfer rate and net electron-hole generation rate are derived as functions of the THz radiation strength for various radiation frequencies from to 6 THz at lattice temperatures T=6 K. It's indicated that the THz radiation with a larger or a lower , has a stronger effect on electron transport and II process. Qualitative agreement is obtained between the calculated electron-hole generation rate and the available experimental data for InAs/AlSb HJ's at T=6 K.