Graphene multilayers with flat moiré minibands can exhibit the quantized anomalous Hall effect due to the combined influence of spontaneous valley polarization and topologically nontrivial valley-projected bands. The sign of the Hall effect in these Chern insulators can be reversed either by applying an external magnetic field, or by driving a transport current through the system. We propose a current-driven mechanism whereby reversal occurs along lines in the (current I, magnetic-field B) control parameter space with slope dI/dB=(e/h)MAM(1-γ2)/γ, where M is the magnetization, AM is the moiré unit cell area, and γ<1 is the ratio of the chemical potential difference between valleys along a domain wall to the electrical bias eV.
|Journal||Physical Review Letters|
|State||Published - Feb 2 2021|
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© 2021 American Physical Society.
ASJC Scopus subject areas
- Physics and Astronomy (all)