Electronic, optical, and transport properties of single-layer ZrTeS4: a DFT study

Abstract

In this paper, we propose the novel ZrTeS₄ single layer and investigate its properties using first-principles calculations. In the equilibrium state, the ZrTeS₄ single layer has an anisotropic lattice with high structural stability. The direct band gap of ZrTeS₄ is found to be approximately 1.89 eV. Like other narrow-band-gap 2D materials, ZrTeS₄ is rather ductile, however its Poisson's ratio is close to that of graphene. Single-layer ZrTeS₄ is expected to be a promising non-linear optical material due to its good birefringence and perfect transparency in most of the infrared region. Single-layer ZrTeS₄ is favorable for hole–electron separation because it only allows fast mobility of electrons along the x-axis. The absorption coefficient α(ω) is very high in the visible region (at 10⁵ cm⁻¹) and ultra-violet region (at 10⁶ cm⁻¹). The electronic and optical properties of single-layer ZrTeS₄ can be tuned by applying different strains. It is reasonable to suggest single-layer ZrTeS₄ as a good candidate for optoelectronic applications.