First principles study of bulk CrSe and CrSe/ZnSe(001) interface

Abstract

Density functional theory calculations are performed to study the structural, electronic, and magnetic properties of hexagonal NiAs type and cubic zinc blende type CrSe structures and interface of zinc blende CrSe with ZnSe(001). We observe that the local density approximation to the exchange correlation energy leads an antiferromagnetic ground state for bulk CrSe, while within generalized gradient approximation, a ferromagnetic state is more stable. The zinc blende structure of CrSe is found to be ferromagnetic half-metal with a total moment of 4μB per formula unit. The results show that the induced tetragonal distortion on ZnSe(001) substrate does not destroy the half-metallicity of zinc blende CrSe. We argue that interface effects in CrSe/ZnSe(001) heterojunctions are not harmful for half-metallicity and are highly localized around interface layer. The Schottky barrier height and band offsets of this interface are calculated and compared with some Heusler alloys/GaAs(001) heterostructures.