First principles study of the electronic and magnetic properties of Zn1-xCoxSe alloys

The spin-polarized density functional theory as implemented within self-consistent plane wave pseudopotential method is used to investigate the electronic and magnetic properties of ternary alloys Zn_1-xCo_xSe (for x = 0.125, 0.25 and 0.375) in zinc blende structure. The spin polarised energy band structures reveals that the Zn_1-xCo_xSe is semiconducting ferromagnet for x = 0.125 and 0.25, it becomes HM ferromagnet for x = 0.375. The band gaps for x = 0.125 and 0.25 configurations are 1.09 and 1.07 eV for spin up channel and 0.65 and 0.39 for spin down channel respectively. The band gaps for x = 0.375 configuration is 0.18 eV for spin up channel. The magnetic moments for x = 0.125 and 0.25 configurations are 3.09 and 3.0 μ_B and for x = 0.375 configuration is 2.97 μ_B. The p-d hybridization reduces the local magnetic moment of Co atom from its free space charge value and induced the small atomic magnetic moment on Zn and Se atoms.