Strain-induced half-metallic ferromagnetism in zinc blende CrP/MnP superlattice: First-principles study

Abstract

Using first-principles calculations within generalized gradient approximation, the electronic and magnetic properties of zinc blende (zb) CrP/MnP superlattice are investigated. The equilibrium lattice constant is calculated to be $5.33\,$\AA. The stability of ferromagnetic zb CrP/MnP superlattice against antiferromagnetism is considered and it is found that the ferromagnetic CrP/MnP superlattice is more stable than the antiferromagnetic one. It is shown that at the equilibrium lattice constant the CrP/MnP superlattice does not show any half metallicity mainly due to the minority $t_{2g}$ states of Cr and Mn. However, if strain is imposed on the CrP/MnP superlattice then the minority $t_{2g}$ electrons shift to higher energies and the proposed superlattice becomes a half-metal ferromagnet. The effect of tetragonal and orthorhombic distortions on the half metallicity of zb CrP/MnP superlattice is also discussed. It is also shown that InP-CrP/MnP/InP is a true half-metal ferromagnet. The half metallicity and magnetization of these superlattices are robust against tetragonal/ orthorhombic deformation.