Type-II band alignment AlN/InSe van der Waals heterostructure: vertical strain and external electric field

Abstract The electronic characteristics of the AlN/InSe van der Waals heterostructure (vdWH) were investigated via employing density functional theory calculations. The vdWH has an indirect band gap with a connatural interlaced-gap type-II band alignment, so the electrons and holes are able to spatially dwell in the InSe and AlN layer, respectively. Especially, the AlN/InSe vdWH owns a higher carrier mobility for both electrons and holes reaching up to 103 cm2 V-1 s-1. Additionally, the electronic properties of the vdWH can be adjusted by vertical strains as well as external electric fields. When imposing a moderate perpendicular electric field, the band gaps of the vdWH vary linearly. It brings a transformation from semiconductor to metal. This work demonstrates that the novel two-dimensional (2D) AlN/InSe vdWH is a vigorous nominee for optoelectronic and nanoelectronic applications.