Quasicrystalline nature of quasicrystal surfaces: A photoemission study

Differently prepared surfaces of quasicrystalline $i-\mathrm{A}\mathrm{l}-\mathrm{P}\mathrm{d}-\mathrm{M}\mathrm{n}$ are analyzed using angle-resolved photoemission in the x-ray and ultraviolet range of photon energies. Depending on the preparation, we find both surfaces with crystalline structure and metallic character, and surfaces with quasicrystalline structural fingerprints and a suppressed density of states at the Fermi level, compatible with a pseudogap.