Enhancement of the decay rate of nonequilibrium carrier distributions due to scattering-in processes

TL;DR

This paper demonstrates that scattering-in processes significantly increase the decay rate of nonequilibrium electron distributions in semiconductors, especially in doped, low-dimensional systems, highlighting an often neglected factor in decay rate calculations.

Contribution

It reveals the substantial impact of scattering-in processes on electron decay rates, which are typically overlooked in existing models.

Findings

Scattering-in processes can dominate decay rates in certain conditions.

Increased decay rates are observed in low-energy electrons in doped semiconductors.

Neglecting scattering-in processes leads to underestimating electron decay rates.

Abstract

We show that, for some semiconductor devices and physical experiments, processes which scatter electrons {\em into} a state $|{\bf k}\rangle$ can contribute strongly to the decay of a nonequilibrium electron occupation of $|{\bf k}\rangle$. For electrons, the decay rate $\gamma({\bf k})$ is given by the sum of the total scattering-out {\em and scattering-in} rates of state $|{\bf k}\rangle$. The scattering-in term, which is often neglected in calculations, increases $\gamma({\bf k})$ of low energy electrons injected into semidegenerate systems, which includes many doped semiconductor structures at nonzero temperatures, particularly those of reduced dimensions.