Surface states and surface stability in half-metallic systems: the cases of zinc-blende-structureMnSb {111}A, {111}B and {001}

Abstract

The surface properties of half-metallic materials can have a profound impact upon theirpossible utility for spintronic devices, and are therefore of significant interest. Here, wepresent the results of comprehensive density functional calculations for the {111}A, {111}B and{001} surfaces of the half-metallic zinc-blende phase of MnSb. We predict trimerized anddimerized reconstructions to be favourable whenever geometrically feasible, and ourthermodynamic analysis strongly suggests termination with an Sb layer in all the casesstudied. The electronic band-structure of the reconstructed Sb-terminated {001} surfaceis found to retain its half-metallicity, whereas the unfavourable Mn-terminatedsurface does not. The reconstructed Sb-terminated {111}A and {111}B surfaces arelikewise half-metallic, and again the unfavourable Mn-terminated surfaces are not.