Magnetotransport in spin-orbit coupled noncentrosymmetric and Weyl metals

Gautham Varma K; Azaz Ahmad; Sumanta Tewari; G. Sharma

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arXiv · 2310.19877

Magnetotransport in spin-orbit coupled noncentrosymmetric and Weyl metals

Gautham Varma K·Azaz Ahmad·Sumanta Tewari·G. Sharma

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Abstract

Recently, chiral anomaly (CA) has been proposed to occur in spin-orbit coupled noncentrosymmetric metals (SOC-NCMs), motivating CA to be a Fermi surface property rather than a Weyl node property. Although the nature of the anomaly is similar in both SOC-NCMs and Weyl systems, here we point out significant fundamental differences between the two. We show that the different nature of the orbital magnetic moment (OMM) in the two systems leads to non-trivial consequences -- particularly the sign of the longitudinal magnetoconductance always remains positive in a SOC non-centrosymmetric metal, unlike a Weyl metal that displays either sign. Furthermore,we investigate the planar Hall effect and the geometrical contribution to the Hall effect in the two systems and point out significant differences in the two systems. We conduct our analysis for magnetic and non-magnetic impurities, making our study important in light of current and upcoming experiments in both SOC-NCMs and Weyl metals.

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Gautham Varma K, Azaz Ahmad, Sumanta Tewari, G. Sharma. 2023-10-30. Magnetotransport in spin-orbit coupled noncentrosymmetric and Weyl metals. https://arxiv.org/abs/2310.19877

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