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arXiv · 2108.03313

Non-local interactions in moiré Hubbard systems

Nicolás Morales-Durán·Nai Chao Hu·Pawel Potasz·Allan H. MacDonald
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Abstract

Moiré materials formed in two-dimensional semiconductor heterobilayers are quantum simulators of Hubbard-like physics with unprecedented electron-density and interaction-strength tunability. Compared to atomic scale Hubbard-like systems, electrons or holes in moiré materials are less strongly attracted to their effective lattice sites because these are defined by finite-depth potential extrema. As a consequence, non-local interaction terms like interaction-assisted hopping and intersite-exchange are more relevant. We theoretically demonstrate the possibility of tuning the strength of these coupling constants to favor unusual states of matter, including spin liquids, insulating ferromagnets, and superconductors.

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Nicolás Morales-Durán, Nai Chao Hu, Pawel Potasz, Allan H. MacDonald. 2022-08-29. Non-local interactions in moiré Hubbard systems. https://doi.org/10.1103/physrevlett.128.217202

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