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arXiv · 2110.11962

Gate-tunable heavy fermion quantum criticality in a moir\'e Kondo lattice

Ajesh Kumar·Nai Chao Hu·Allan H. MacDonald·Andrew C. Potter
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Abstract

We propose a realization of Kondo-lattice physics in moir\'e superlattices at the interface between a WX$_2$ homobilayer and MoX$_2$ monolayer (where X=S,Se). Under appropriate gating conditions, the interface-WX$_2$-layer forms a triangular lattice of local moments that couple to itinerant electrons in the other WX$_2$-layer via a gate-tunable Kondo exchange interaction. Using a parton mean-field approach we identify a range of twist-angles which support a gate-tuned quantum phase transition between a heavy-fermion liquid with large anomalous Hall conductance and a fractionalized chiral spin-liquid coexisting with a light Fermi liquid, and describe experimental signatures to distinguish among competing theoretical scenarios.

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Ajesh Kumar, Nai Chao Hu, Allan H. MacDonald, Andrew C. Potter. 2021-10-22. Gate-tunable heavy fermion quantum criticality in a moir\'e Kondo lattice. https://doi.org/10.1103/physrevb.106.l041116

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