Electronic band dispersion and pseudogap in quasicrystals: Angular-resolved photoemission studies on icosahedral Al70Pd21.5Mn8.5.
نویسندگان
چکیده
Angular-resolved photoelectron spectra from the fivefold surface of single-grain icosahedral Al70Pd21.5Mn8.5 exhibit a quasiperiodic dispersion of 300 meV at 2.3 eV binding energy. Low energy electron diffraction studies confirm quasicrystalline order at the surface. A distinct pseudogap feature is observed with a density of states near the Fermi level decreasing as a square-root power law.
منابع مشابه
Absence of fine structure in the photoemission spectrum of the icosahedral Al-Pd-Mn quasicrystal
The results of the low-temperature ultrahigh-energy-resolution photoemission studies of a single-grain icosahedral alloy Al70Pd21.5Mn8.5 have been presented. The existence of the theoretically predicted pseudogap in the density of states at the Fermi energy has been confirmed. No evidence of the theoretically predicted spikiness of the density of states could be observed. It has been suggested ...
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عنوان ژورنال:
- Physical review letters
دوره 75 24 شماره
صفحات -
تاریخ انتشار 1995