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arXiv · 1305.2272

Transport anomalies due to anisotropic interband scattering

Maxim Breitkreiz·P. M. R. Brydon·Carsten Timm
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Abstract

Unexpected transport behavior can arise due to anisotropic single-particle scattering in multiband systems. Specifically, we show within a semiclassical Boltzmann approach beyond the relaxation-time approximation that anisotropic scattering between electronlike and holelike Fermi surfaces generically leads to negative transport times, which in turn cause negative magnetoresistance, an extremum in the Hall coefficient, and a reduction of the resistivity. The anisotropy required for this to occur decreases with increasing mismatch between the Fermi-surface radii.

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Maxim Breitkreiz, P. M. R. Brydon, Carsten Timm. 2013-05-10. Transport anomalies due to anisotropic interband scattering. https://doi.org/10.1103/physrevb.88.085103

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