Building Alloys from Single Atoms: Au−Pd Chains on NiAl(110)

Abstract

Well-ordered mono-elemental and alloy chains have been assembled from single Au and Pd atoms on a NiAl(110) surface with a scanning tunneling microscope. Spatially resolved conductance measurements revealed the development of quantum well states in the different atomic chains, which are aligned on free-electron like bands. Effective electron mass and onset energy of states in mixed Au−Pd chains lie between the values obtained for pure Au and Pd chains. The results demonstrate effective hybridization of Au and Pd induced states to a delocalized electronic system, in correspondence with the perfect miscibility of the respective bulk materials.