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Boltzmann-equation approach to anomalous transport in a Weyl metal

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 نشر من قبل Ki Seok Kim
 تاريخ النشر 2014
  مجال البحث فيزياء
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Weyl metal is regarded as a platform toward interacting topological states of matter, where its topological structure gives rise to anomalous transport phenomena, referred to as chiral magnetic effect and negative magneto-resistivity, the origin of which is chiral anomaly. Recently, the negative magneto-resistivity has been observed with the signature of weak anti-localization at $x = 3 sim 4 ~ %$ in Bi$_{1-x}$Sb$_{x}$, where magnetic field is applied in parallel with electric field. Based on the Boltzmann-equation approach, we find the negative magneto-resistivity in the presence of weak anti-localization. An essential ingredient is to introduce the topological structure of chiral anomaly into the Boltzmann-equation approach, resorting to semi-classical equations of motion with Berry curvature.

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