Surfactant-mediated growth of AuAl2 film on a decagonal Al72Ni12Co16 quasicrystal

In an effort to produce an epitaxial quasicrystalline film of simple substances, Au was deposited on the quasiperiodic surface of a decagonal Al72Ni12Co16 quasicrystal. In the case of a submonolayer deposition, the Au layer is crystallized with annealing and transformed into a multiply twinned AuAl2 crystalline layer with (1 1 0)-oriented surface. This was not the case for multilayer Au. However, predeposition of In on the quasiperiodic surface affected the behavior of the Au overlayer significantly. It was found that In acted as a surfactant and promoted the epitaxial crystallization of the Au overlayer, giving rise to the formation of multiply twinned AuAl2 crystals with annealing.