Cr2S3 a bipolar semiconducting fully compensated ferrimagnet

Abstract

The promises of spintronics have longed for the realization of fully compensated states and full spin polarization. Half-metallic/half-semiconducting (HM/HS) and fully compensated materials are suggested as candidates. We use density functional theory to report that the experimentally realized rhombohedral ${\mathrm{Cr}}_{2}{\mathrm{S}}_{3}$ is a promising candidate as a bipolar magnetic semiconducting (BMS)/HS fully compensated ferrimagnetic (FCFiM) material. Our calculations demonstrate that the uniquely layered structure of ${\mathrm{Cr}}_{2}{\mathrm{S}}_{3}$ produces different interlayer and intralayer $d\text{\ensuremath{-}}p\text{\ensuremath{-}}d$ hybridization schemes between Cr atoms. Strong interlayer and weak intralayer antiferromagnetic coupling between different Cr sites make the overall magnetic state a fully compensated structure. The origin of BMS/HS and fully compensated state has been explained by a structural analysis, where magnetic exchange interaction between Cr sites is dependent on bond distance and bond angle of each Cr-centered octahedron. Furthermore, by applying strains perpendicular to the basal plane, distortion of Cr octahedron sites and Cr--Cr distance is altered, resulting in the phase transition of the material both electronically and magnetically from BMS-FCFiM to HS-FCFiM to ferrimagnetic (FiM). These studies enable us to rediscover ${\mathrm{Cr}}_{2}{\mathrm{S}}_{3}$ as a novel class of BMS materials.