First-principles calculations on the mechanical, electronic, magnetic and optical properties of two-dimensional Janus Cr2TeX (X= P, As, Sb) monolayers

Abstract

Janus materials possess extraordinary physical, chemical, and mechanical properties caused by symmetry breaking. Here, the mechanic properties, electronic structure, magnetic properties, and optical properties of Janus Cr2TeX (X= P, As, Sb) monolayers are systematically investigated by the density functional theory. Janus Cr2TeP, Cr2TeAs, and Cr2TeSb are intrinsic ferromagnetic (FM) half-metals with wide band gaps between spin-down channel and half-metallic gaps. The Curie temperature (Tc) of these monolayers are about 583, 608, and 597 K, respectively by Monte Carlo simulations based on the Heisenberg model. Additionally, it has been found that Cr2TeX (X= P, As, Sb) monolayers still exhibit FM half-metallic properties under biaxial strain ranging from −6% to 6%. At last, the Cr2TeP monolayer has a higher absorption coefficient than the Cr2TeAs and Cr2TeSb monolayers in the visible region. The results predict that Janus Cr2TeX (X= P, As, Sb) monolayers with novel properties have good potential for applications in future nanodevices.