Original scientific paper
Electrical conductivity, Hall coefficient and thermoelectric power of icosahedral i-Al62Cu25.5Fe12.5 and i-Al63Cu25Fe12 quasicrystals
A. Bilušić
; Institute of Physics, HR-10001 Zagreb, P.O. Box 304, Croatia
I. Bešlić
; Institute of Physics, HR-10001 Zagreb, P.O. Box 304, Croatia; Insitute for Medical Research and Occupational Health, Zagreb, Croatia
J. Ivkov
; Institute of Physics, HR-10001 Zagreb, P.O. Box 304, Croatia
J. C. Lasjaunias
; Centre de Recherches sur les Tres Basses Temperatures, Laboratoire associea l'Universite Joseph Fourier, CNRS, 38042 Grenoble, France
A. Smontara
; Institute of Physics, HR-10001 Zagreb, P.O. Box 304, Croatia
Abstract
The electrical conductivity, Hall coefficient and thermoelectric power of icosahedral i-Al62Cu25.5Fe12.5 quasicrystal samples in the temperature range 2 K - 340 K are measured, and comparison with icosahedral i-Al63Cu25Fe12 quasicrystal samples is made. We have analysed the temperature dependence of the conductivity below 70 K and the results of this analysis are consistent with the predictions of the weak-localisation and the electron-electron interaction theories. The temperature dependence of the electrical conductivity, Hall coefficient and thermoelectric power above 40 K are consistently explained by a two-band model. Although the overlapping of the valence and conduction bands at Fermi level is responsible for the coexistence of both types of carriers, and it enables us to describe quasicrystals as semi-metals, the temperature variation of the electrical conductivity is determined by that of carrier density which makes the situation essentially the same as that in normal semiconductors.
Keywords
electrical conductivity; Hall coefficient; thermoelectric power; icosahedral quasicrystals; i-Al62Cu25.5Fe12.5; i-Al63Cu25Fe12; weak-localisation theory; electron-electron interaction theory; two-band model
Hrčak ID:
300972
URI
Publication date:
1.7.1999.
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