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
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.
PACS: 73.50.Fq – High-field and nonlinear effects / 72.10.-d – Theory of electronic transport; scattering mechanisms / 72.20.-i – Conductivity phenomena in semiconductors and insulators
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002
