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Fine structure in the electronic density of states of Al-Ni-Co decagonal quasicrystal from ultrafast time-resolved optical reflectivity

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 نشر من قبل Tomaz Mertelj
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف T. Mertelj




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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.



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