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arXiv · 2207.02178

Intrinsic nonlinear conductivities induced by the quantum metric

Kamal Das·Shibalik Lahiri·Rhonald Burgos Atencia·Dimitrie Culcer·Amit Agarwal
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Abstract

The second-order nonlinear current originates from three physical mechanisms: extrinsic nonlinear Drude and Berry curvature dipole and intrinsic Berry connection polarizability. Here, we predict a new intrinsic contribution to the current related to the quantum metric, a quantum geometric property of the electronic wave function. This contribution manifests in systems that simultaneously break the time-reversal and the inversion symmetry. Interestingly, the new contribution is dissipative in nature and contributes to both longitudinal and the dissipative nonlinear Hall response. The quantum metric-induced NL current dominates transport in parity-time reversal symmetric systems near the band edges, something we show explicitly for topological antiferromagnets.

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Kamal Das, Shibalik Lahiri, Rhonald Burgos Atencia, Dimitrie Culcer, Amit Agarwal. 2022-07-05. Intrinsic nonlinear conductivities induced by the quantum metric. https://arxiv.org/abs/2207.02178

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