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arXiv · 2204.10865

Continuous Mott transition in moir\'e semiconductors: role of long-wavelength inhomogeneities

Sunghoon Kim·T. Senthil·Debanjan Chowdhury
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Abstract

Recent experiments in moir\'{e} transition metal dichalcogenide materials have reported the observation of a continuous bandwidth-tuned transition from a metal to a paramagnetic Mott insulator at a fixed filling of one electron per moir\'{e} unit cell. The electrical transport measurements reveal a number of puzzling features that are seemingly at odds with the theoretical expectations of an interaction induced, but disorder-free, bandwidth-tuned metal-insulator transition. In this work, we include the effects of long-wavelength inhomogeneities, building on the results for a continuous metal-insulator transition at fixed filling in the clean limit. We examine the effects of meso-scale inhomogeneities near the critical point on transport using the framework of random resistor networks, highlighting the salient differences from a simple percolation-based picture. We place our results in the context of recent and ongoing experiments.

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Sunghoon Kim, T. Senthil, Debanjan Chowdhury. 2022-04-22. Continuous Mott transition in moir\'e semiconductors: role of long-wavelength inhomogeneities. https://doi.org/10.1103/physrevlett.130.066301

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