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Magnetoconductivity of icosahedral and amorphous Al-Pd-Re films - a comparison

R. Haberkern·R. Rosenbaum·H. Bekar·M. Pilosof·A. Milner·A. Gerber·P. Häussler
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Abstract

The magnetoconductivity of quasicrystals is often discussed in the frame of quantum corrections, namely weak (anti-) localiza-tion and electron-electron interaction. A premise for both effects is a strong elastic scattering of conduction electrons. Amorphous and icosahedral phases are discussed as Hume-Rothery alloys with an electronically induced structural peak at the diameter of the Fermi sphere. Therefore, both should exhibit quantum corrections. The preparation of quasicrystalline films via the amorphous route offers the possibility to compare the magnetoconductivity on samples of identical composition but different structure. We report on magnetoconduc-tivity measurements at temperatures between 0.2 K and 22 K and for magnetic fields up to 16 T. With the exception of the electronic diffusion constant, amorphous as well as icosahedral Al-Pd-Re films can be described by nearly the same set of parameters if the samples are well on the metallic side of the metal-insulator transition.

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R. Haberkern, R. Rosenbaum, H. Bekar, M. Pilosof, A. Milner, A. Gerber, P. Häussler. 2000-01-14. Magnetoconductivity of icosahedral and amorphous Al-Pd-Re films - a comparison. https://arxiv.org/abs/cond-mat/0001209

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