Field effect on the impact ionization rate in semiconductors

摘要: Impact ionization plays a crucial role for electron transport in semiconductors at high electric fields. We derive appropriate quantum kinetic equations within linear response theory. The field-dependent collision integral is evaluated the process of impact ionization. A known, essentially analytical result reproduced parabolic band approximation [W. Quade et al., Phys. Rev. B 50, 7398 (1994)]. Based on numerical results zero field strengths but realistic structures, fit formula proposed respective rate. Explicit are given GaAs, Si, GaN, ZnS, and SrS.