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Quantum-oscillation-modulated angular dependences of the positive longitudinal magnetoconductivity and planar Hall effect in Weyl semimetals

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 نشر من قبل Ming-Xun Deng
 تاريخ النشر 2019
  مجال البحث فيزياء
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We study the positive longitudinal magnetoconductivity (LMC) and planar Hall effect as emergent effects of the chiral anomaly in Weyl semimetals, following a recent-developed theory by integrating the Landau quantization with Boltzmann equation. It is found that, in the weak magnetic field regime, the LMC and planar Hall conductivity (PHC) obey $cos^{6}theta$ and $cos^{5}thetasin theta$ dependences on the angle $theta$ between the magnetic and electric fields. For higher magnetic fields, the LMC and PHC cross over to $cos^{2}theta$ and $costhetasintheta$ dependences, respectively. Interestingly, the PHC could exhibit quantum oscillations with varying $theta$, due to the periodic-in-$1/B$ oscillations of the chiral chemical potential. When the magnetic and electric fields are noncollinear, the LMC and PHC will deviate from the classical $B$-quadratic dependence, even in the weak magnetic field regime.

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