Multiband [formula omitted] theory for monolayer AsP: Symmetry, strain and spin-orbit coupling

Abstract

Multiband k∙p model have been constructed for the monolayer AsP. Six conductance and six valence bands are included capable of describing the energy band dispersion, spin-orbit coupling, and strain effect, in good agreement with the first-principle results. Spin-orbit coupling strength has been confirmed. Interestingly, even when applying a small strain, the valence bands show enormous change. The competition between the valence bands causes such behavior and can be fully understood by simple formulas derived through our k∙p theory. This k∙p theory provides a simple and convenient way to understand and manipulate the optical and transport properties of monolayer AsP and their nanostructures by strain and external fields. AsP is a typical compound of a new family of two-dimensional group-VA materials, our k∙p theory can be easily extended to understand the other compounds of this material family.