Novel wide spectrum light absorber heterostructures based on hBN/In(Ga)Te

Abstract

Two-dimensional group III monochalcogenides have recently attracted quite attention for their wide spectrum of optical and electric properties, being promising candidates for optoelectronic and novel electrical applications, however in their pristine form they are very sensitive and vulnerable to oxygen in air. Here we present two newly designed vdW heterostructures based on hBN (hexagonal boron nitride) and GaTe or InTe monolayer. Using density functional theory we investigate electronic and optical properties of those structures. Their moderate band gap and an good absorption coefficient makes them excellent for absorbers in wide spectrum, covering all from part of IR to far UV spectrum, with particularly good absorption of UV light. The hBN layer which can be beneficial for protection of sensitive GaTe and InTe does not only preserve their optical properties but also enhances it. Moreover, we confirm that type of stacking does not affect any relevant properties, as all three stacking types are very similar in total energy and bandstructure is almost the same for every one. This is especially important for easier experimental realization.