Electronic transport properties of high-resistivity icosahedral AlPdRe below 1 K
2002 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 65, no 9Article in journal (Refereed) Published
The temperature dependence of the conductivity, sigma(T), and the magnetoresistance up to B = 6 T have been studied in the temperature range 0.01 Kless than or equal toTless than or equal to1 K for two differently prepared i-AlPdRe samples on the insulating side of the metal-insulator transition. sigma(T) for both samples was observed to saturate in zero magnetic field below about 20 mK. With increasing magnetic field the temperature dependence of the conductivity increased, and at 6 T, or(T,B = 6 T) was found to decrease linearly with decreasing temperature down to the lowest measurement temperature of 10 mK. The estimated value of the conductivity at T=0 K, sigma(0 K), was found to decrease strongly with increasing resistance ratio R [ = rho(4 K)/rho(295 K)] over a wide range of R values and for differently prepared samples, suggesting that a finite sigma(0,R) is a characteristic property of the icosahedral phase of high-resistivity i-AlPdRe. The magnetoresistance is positive below 1 K. The relation Deltarho(B)/rhosimilar toB(2) is followed at larger fields by a B-2/3 dependence. With decreasing temperature these characteristic field regions are successively depressed towards smaller magnetic fields and eventually become unobservable. A scaling of the magnetoresistance is found for data in the region Tless than or equal to1 K, Bless than or equal to6 T of the form [Deltarho(B)/rho]/T-alpha=f(B/T) for each sample, with alpha about 0.3 for both samples.
Place, publisher, year, edition, pages
2002. Vol. 65, no 9
metal-insulator-transition, al-pd-re, low-temperature conductivity, crystal i-alpdre, quasi-crystals, weak-localization, system, magnetoconductance, magnetoresistance, alloys
IdentifiersURN: urn:nbn:se:kth:diva-21405DOI: 10.1103/PhysRevB.65.094206ISI: 000174547900058OAI: oai:DiVA.org:kth-21405DiVA: diva2:340103
QC 201005252010-08-102010-08-10Bibliographically approved