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arXiv · 2205.15120

Nonlinear anomalous Hall effects probe topological phase-transitions in twisted double bilayer graphene

Atasi Chakraborty·Kamal Das·Subhajit Sinha·Pratap Chandra Adak·Mandar M. Deshmukh·Amit Agarwal
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Abstract

Nonlinear anomalous Hall effect is the Berry curvature dipole induced second-order Hall voltage or temperature difference in response to a longitudinal electric field or temperature gradient. These are the prominent Hall responses in time reversal symmetric systems. Here, we investigate the family of second-order nonlinear anomalous Hall effects, the electrical, thermoelectric and thermal nonlinear Hall effects in the moiré system of twisted double bilayer graphene. We demonstrate that the nonlinear anomalous Hall signals can be used to probe the topological phase-transitions in moiré systems, induced by a perpendicular electric field. Specifically, we show that the whole family of nonlinear anomalous Hall responses undergo a sign reversal across a topological phase-transition.

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Atasi Chakraborty, Kamal Das, Subhajit Sinha, Pratap Chandra Adak, Mandar M. Deshmukh, Amit Agarwal. 2022-05-30. Nonlinear anomalous Hall effects probe topological phase-transitions in twisted double bilayer graphene. https://doi.org/10.1088/2053-1583%2Fac8b93

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