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arXiv · 2412.10584

Winding Berry dipole on uniaxially strained graphene/hBN/hBN moir\'e trilayers

Angiolo Huaman·Salvador Barraza-Lopez
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Abstract

Nonlinear Hall-like currents can be generated by a time-periodic alternating bias on two-dimensional (2D) materials lacking inversion symmetry. To hint that the moir\'e between graphene and its supporting substrate contributes to the homogeneity of nonlinear currents, the change in the local potential $\Delta V(r)$ around horizontally strained graphene due to a homobilayer of hexagonal boron nitride (hBN) was obtained from ab initio calculations, and corrections to on-site energies and hopping matrix elements on graphene's tight-binding electronic dispersion of $\pi-$electrons were calculated. Relying on a semiclassical approximation, Berry dipoles $D$ are seen to change orientation and wind throughout the moir\'e lattice.

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Angiolo Huaman, Salvador Barraza-Lopez. 2024-12-13. Winding Berry dipole on uniaxially strained graphene/hBN/hBN moir\'e trilayers. https://doi.org/10.1103/physrevb.111.l041103

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