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FIZIKA A 8 (1999) 3 , 183-194
 
ELECTRICAL CONDUCTIVITY, HALL COEFFICIENT AND THERMOELECTRIC POWER OF
ICOSAHEDRAL i-Al62Cu25.5Fe12.5 AND i-Al63Cu25Fe12
QUASICRYSTALS
A. BILUŠIĆa, I. BEŠLIĆa,b, J. IVKOVa,
J. C. LASJAUNIASc and A. SMONTARAa
aInstitute of Physics, HR-10001 Zagreb, P.O. Box 304,
Croatia
bInsitute for Medical Research and Occupational Health,
Zagreb, Croatia
cCentre de Recherches sur les Tres Basses Temperatures,
Laboratoire associea l'Universite Joseph Fourier, CNRS, 38042 Grenoble, France
Dedicated to Professor Boran Leontić on the occasion of his 70th
birthday
Received 16 December 1999; revised manuscript received 31 January 2000
Accepted 21 February 2000
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.
PACS numbers: 61.44.Br, 71.23.Ft, 72.15.Jf, 73.20.Fz
UDC 537.32, 537.12,537.633.2
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
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