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arXiv · 2509.11670

Exchange and spin-orbit proximity driven topological and transport phenomena in twisted graphene/CrI$_3$ heterostructures

M. Jafari·M. Gmitra·A. Dyrdał
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Abstract

We present results of comprehensive first-principles and kp-method studies of electronic, magnetic, and topological properties of graphene on a monolayer of CrI$_3$. First, we identify a twist angle between the graphene and CrI$_3$, that positions the graphene Dirac cones within the bandgap of CrI$_3$. Then, we derive the low-energy effective Hamiltonian describing electronic properties of graphene Dirac cones. Subsequently, we examine anomalous and valley Hall conductivity and discuss possible topological phase transition from a quantum anomalous Hall insulator to a trivial insulating state, concomitant a change in the magnetic ground state of CrI$_3$. These findings highlight the potential of strain engineering in two-dimensional van der Waals heterostructures for controlling topological and magnetic phases.

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M. Jafari, M. Gmitra, A. Dyrdał. 2025-09-15. Exchange and spin-orbit proximity driven topological and transport phenomena in twisted graphene/CrI$_3$ heterostructures. https://arxiv.org/abs/2509.11670

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