Volume 63, Number 1, July 2003
|Page(s)||63 - 68|
|Section||Condensed matter: structure, mechanical and thermal properties|
|Published online||01 June 2003|
Semiconductivity in aluminum–transition-metal quasicrystalline alloys induced by ordering in six dimensions
Institut für Materialphysik and Center for Computational Materials Science Universität Wien - Sensengasse 8/12, A-1090 Wien, Austria
2 Institute of Physics, Slovak Academy of Sciences Dúbravská cesta 9, SK-84228 Bratislava, Slovak Republic
Accepted: 2 May 2003
We report on a class of icosahedral aluminum–transition-metal (-TM) alloys with true semiconducting behavior. The existence of a semiconducting gap is found to depend critically on a particular kind of -TM ordering defined by a simple rule in the 6-dimensional superspace. Any deviation from this 6D order leads to the formation of strongly localized defect states in the gap. We show that by a judicious selection of transition metals to be alloyed with , we can find alloys with a semiconducting gap at the Fermi level for a hierarchy of approximants to a quasicrystal. As the electron/atom ratio placing the Fermi level into the gap is slightly different for each approximant, this suggests that the gap persists also in the quasiperiodic limit. Icosahedral -- turns out to be a semiconductor with a band gap filled by the localized states.
PACS: 61.44.Br – Structure of solids and liquids; crystallography: Quasicrystals / 71.20.-b – Electron density of states and band structure of crystalline solids / 71.23.Ft – Electronic structure of bulk materials: Quasicrystals
© EDP Sciences, 2003
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.