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arXiv · 1909.09341

Emergent magnetic texture in driven twisted bilayer graphene

D. A. Bahamon·G. Gómez-Santos·T. Stauber
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Abstract

The transport properties of a twisted bilayer graphene barrier are investigated for various twist angles. Remarkably, for small twist angles around the magic angle $\theta_m \sim 1.05^{\circ}$, the local currents around the AA-stacked regions are strongly enhanced compared to the injected electron rate. Furthermore, the total and counterflow (magnetic) current patterns show high correlations in these regions, given rise to well-defined magnetic moments that form a magnetic Moir\'e superlattice. The orientation and magnitude of these magnetic moments changes as function of the gate voltage and possible implications for emergent spin-liquid behaviour are discussed.

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D. A. Bahamon, G. Gómez-Santos, T. Stauber. 2019-09-20. Emergent magnetic texture in driven twisted bilayer graphene. https://doi.org/10.1039/d0nr02786c

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