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arXiv · 2407.14583

Correlated Topological Mixed-Valence Insulators in Moir\'e Hetero-Bilayers

Juan Felipe Mendez-Valderrama·Sunghoon Kim·Debanjan Chowdhury
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Abstract

Moir\'e transition metal dichalcogenide (TMD) materials provide an ideal playground for studying the combined interplay of strong interactions and band-topology over a range of electronic fillings. Here we investigate the panoply of interaction-induced electronic phases that arise at a total commensurate filling of $\nu_T=2$ in moir\'e TMD heterobilayers, focusing specifically on their renormalized band-topology. We carry out a comprehensive self-consistent parton mean-field analysis on an interacting mixed-valence Hamiltonian describing AB-stacked MoTe$_2$/WSe$_2$ to highlight different ingredients that arise due to "Mottness", band-flattening, an enhanced excitonic tendency, and band-inversion, leading to correlated topological semi-metals and insulators. We also propose a possible route towards realizing fractionalized insulators with emergent neutral fermionic excitations in this and other closely related platforms.

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Juan Felipe Mendez-Valderrama, Sunghoon Kim, Debanjan Chowdhury. 2024-07-19. Correlated Topological Mixed-Valence Insulators in Moir\'e Hetero-Bilayers. https://doi.org/10.1103/physrevb.110.l201105

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