First-principles study on magnetism and half-metallicity in bulk and various (001) surfaces of Heusler alloy Zr_2VSn with Hg_2CuTi-type structure

摘要

Structural, electronic and magnetic properties in the bulk and five different (001) surfaces (ZrV-, ZrSn-, VV-, ZrZr- and SnSn-terminations) of Zr_2VSn Heusler alloy with Hg_2CuTi-type structure are studied by using first-principles calculations based on density-functional theory. The bulk Zr_2VSn Heusler alloy is ferrimagnetic half-metallicity with equilibrium lattice constant 6.815 A and total magnetic moment -1.000 μ_B/f.u., following the Slater-Pauling rule μ_t = Z_t - 18. The atoms on different surface layers exhibit different displacements, electronic and magnetic properties. All five (001) surfaces lose the half-metallicity and are not usable in spintronics devices.