Atom-Rich and Defect Effects on Electronic Structure and Magnetism in Co2MnGe/MgO Heterojunction

We investigated the atomic rich and defect effects on the half-metallicity of the full-Heusler alloy Co2MnGe from the first principles. Our results show that both Mn-rich and Co-rich could increase the tunnel magnetoresistance (TMR) of the Co2MnGe/MgO magnetic tunnel junctions (MTJs). As for defect, all of investigated Co, Mn and Ge defect show that the spin polarization at Efand the TMR in the MTJs with Co and Mn defect is significatively decreased except for Ge-defected MTJs.