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arXiv · 2404.13451

Intrinsic anomalous, spin and valley Hall effects in ex-so-tic van-der-Waals structures

I. Wojciechowska·A. Dyrdal
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Abstract

We consider the anomalous, spin, valley, and valley spin Hall effects in a pristine ex-so-tic graphene-based van-der-Waals (vdW) heterostructure consisting of a bilayer graphene (BLG) between semiconducting van-der-Waals material with strong SOC (e.g., WS$_2$) and ferromagnetic and insulating vdW material (e.g. Cr$_2$Ge$_2$Te$_6$). Reducing the effective Hamiltonian derived by Zollner et al [Phys. Rev. Lett. 125(19), 196402 (2020)] to low-energy states, and using the Green function formalism, we derived analytical results for the Hall conductivities as a function of the Fermi level and gate voltage. Depending on these parameters, we found quantized valley conductivity.

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I. Wojciechowska, A. Dyrdal. 2024-04-20. Intrinsic anomalous, spin and valley Hall effects in ex-so-tic van-der-Waals structures. https://arxiv.org/abs/2404.13451

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