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On the origin of unusual transport properties observed in densely packed polycrystalline CaAl_{2}

S. Sergeenkov·F. M. Araujo-Moreira
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Abstract

A possible origin of unusual temperature behavior of transport coefficients observed in densely packed polycrystalline CaAl_{2} compound [M. Ausloos et al., J. Appl. Phys. 96, 7338 (2004)] is discussed, including a power-like dependence of resistivity with $ρ\propto T^{-3/4}$ and N-like form of the thermopower. All these features are found to be in good agreement with the Shklovskii-Efros localization scenario assuming polaron-mediated hopping processes controlled by the Debye energy.

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S. Sergeenkov, F. M. Araujo-Moreira. 2007-01-18. On the origin of unusual transport properties observed in densely packed polycrystalline CaAl_{2}. https://doi.org/10.1063/1.2364667

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