Surface atomic structure of alloyed Mn5Ge3(0001) by scanning tunneling microscopy

Abstract

Surface atomic structure of Mn5Ge3(0 0 0 1) is Studied by scanning tunneling microscopy. Hexagonal honeycomb ordering is observed at high energy levels, vertical bar E - E-F vertical bar similar to 1.2 eV, on the flat regions of three-dimensional Mn5Ge3 islands. At low energy levels, vertical bar E - E-F vertical bar similar to 0.5 eV, however, atomic images exhibit dot-array and ring-array structures, which show complete and partial contrast inversion, compared to the honeycomb ordering. Experimental observations are discussed on the basis of possible atomic models. (C) 2007 Elsevier B.V. All rights reserved.