Relaxation times and charge conductivity of silicene

TL;DR

This paper studies how impurities affect charge transport and relaxation times in silicene, showing that electrical control over conductivity and band gap makes it promising for electronic applications.

Contribution

It provides a detailed analysis of relaxation times and conductivity in silicene considering spin-orbit interaction and screening effects, highlighting controllability for device use.

Findings

Transport relaxation time exceeds single particle relaxation time.

Conductivity can be tuned via external electric field.

Results applicable to similar buckled honeycomb materials.

Abstract

We investigate the transport and single particle relaxation times of silicene in the presence of neutral and charged impurities. The static charge conductivity is studied using the semiclassical Boltzmann formalism when the spin-orbit interaction is taken into account. The screening is modeled within Thomas-Fermi and random phase approximations. We show that the transport relaxation time is always longer than the single particle one. Easy electrical controllability of both carrier density and band gap in this buckled two-dimensional structure makes it a suitable candidate for several electronic and optoelectronic applications. In particular, we observe that the dc charge conductivity could be easily controlled through an external electric field, a very promising feature for applications as electrical switches and transistors. Our findings would be qualitatively valid for other buckled honeycomb lattices of the same family, such as germanine and stanine.