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arXiv · 2105.07008

Quantum Phases of Transition Metal Dichalcogenide Moir\'e Systems

Yiqing Zhou·D. N. Sheng·Eun-Ah Kim
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Abstract

Moir\'e systems provide a rich platform for studies of strong correlation physics. Recent experiments on hetero-bilayer transition metal dichalcogenide (TMD) Moir\'e systems are exciting in that they manifest a relatively simple model system of an extended Hubbard model on a triangular lattice. Inspired by the prospect of the hetero-TMD Moir\'e system's potential as a solid-state-based quantum simulator, we explore the extended Hubbard model on the triangular lattice using the density matrix renormalization group (DMRG). Specifically, we explore the two-dimensional phase space of the kinetic energy relative to the interaction strength $t/U$ and the further-range interaction strength $V_1/U$. We find competition between Fermi fluid, chiral spin liquid, spin density wave, and charge density wave. In particular, our finding of the optimal further-range interaction for the chiral correlation presents a tantalizing possibility.

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Yiqing Zhou, D. N. Sheng, Eun-Ah Kim. 2021-05-14. Quantum Phases of Transition Metal Dichalcogenide Moir\'e Systems. https://doi.org/10.1103/physrevlett.128.157602

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