Electronic structures, magnetic properties and half-metallicity in Heusler alloys Zr2CoZ (Z=Al, Ga, In, Sn)

• The Zr2CoZ (Z=Al, Ga, In, Sn) are HM ferrimagnets within a wide range of lattice constant.
• The indirect band gaps of Zr2CoZ are located in minority spin channel.
• The total magnetic moments of Zr2CoZ obey the Slater–Pauling rule μt=Zt−18μt=Zt−18.

The electronic structures, magnetic properties, and half-metallicity of full-Heusler alloys Zr2CoZZr2CoZ (Z=Al, Ga, In, Sn) with the Hg2CuTiHg2CuTi-type structure have been studied by using the first-principles projector augmented wave (PAW) potential within the generalized gradient approximation (GGA). The Zr2CoZZr2CoZ (Z=Al, Ga, In, Sn) are found to be half-metallic ferrimagnets within a certain range of the lattice constant. The total magnetic moments (μtμt) of the Zr2CoZZr2CoZ alloys are calculated to be 2 for Z=Al, Ga, In and 3 for Z=Sn, linearly scaled with the total number of valence electrons (ZtZt) by μt=Zt−18μt=Zt−18. The origin of the band gap for these half-metallic alloys is well understood. These new Zr-based Heusler alloys are the ideal candidates for spintronic devices.