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arXiv · 2301.02248

Optical Control of Slow Topological Electrons in Moiré Systems

Christopher Yang·Iliya Esin·Cyprian Lewandowski·Gil Refael
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Abstract

Floquet moiré materials possess optically-induced flat-electron bands with steady-states sensitive to drive parameters. Within this regime, we show that strong interaction screening and phonon bath coupling can overcome enhanced drive-induced heating. In twisted bilayer graphene (TBG) irradiated by a terahertz-frequency continuous circularly polarized laser, the extremely slow electronic states enable the drive to control the steady state occupation of high-Berry curvature electronic states. In particular, above a critical field amplitude, high-Berry-curvature states exhibit a slow regime where they decouple from acoustic phonons, allowing the drive to control the anomalous Hall response. Our work shows that the laser-induced control of topological and transport physics in Floquet TBG are measurable using experimentally available probes.

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Christopher Yang, Iliya Esin, Cyprian Lewandowski, Gil Refael. 2023-05-17. Optical Control of Slow Topological Electrons in Moiré Systems. https://doi.org/10.1103/physrevlett.131.026901

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