Epitaxial film growth on a decagonal Al₇₂Ni₁₂Co₁₆ quasicrystal

We performed Pt depositions onto the 10-fold surface of a decagonal Al-Ni-Co quasicrystal to investigate the nature of film growth on quasiperiodic surfaces. Although no epitaxial films were obtained on the clean 10-fold surface, Pt deposition on the In-predeposited surface and subsequent annealing yielded an epitaxial layer of multiply twinned PtAl₂ crystals. As observed in Au depositions onto the same surface, In acted as a surfactant and promoted two-dimensional growth of the overlayer with annealing.