Fine structure in the electronic density of states of Al-Ni-Co decagonal   quasicrystal from ultrafast time-resolved optical reflectivity
  We measured the temperature and fluence dependence of the time-resolved photoinduced optical reflectivity in a decagonal Al_{71.9}Ni_{11.1}Co_{17.0} quasicrystal. We find no evidence for the relaxation of a hot thermalized electron gas as observed in metals. Instead, a quick diffusion of the hot nonthermal carries ~40 nm into the bulk is detected enhanced by the presence of a broad ~1 eV pseudogap. From the relaxation dynamics we find an evidence for the presence of a fine structure in the electronic density of states around ~13 meV from the Fermi energy. The structure is related to a weak bottleneck for the carrier relaxation observed at low temperatures. 
T. Mertelj (1,2), A. Oslak (1), J. Dolinsek (1,2), I. R. Fisher (3),   V.V. Kabanov (1), D. Mihailovic (1,2) ((1) Jozef Stef...