Quantum Phases of Transition Metal Dichalcogenide Moir\'e Systems

TL;DR

This paper investigates the quantum phases of hetero-bilayer transition metal dichalcogenide Moiré systems, revealing various competing states and the conditions favoring chiral spin liquids, using advanced numerical methods.

Contribution

It applies the density matrix renormalization group to explore the extended Hubbard model on a triangular lattice, identifying phase competition and optimal conditions for chiral correlations.

Findings

Identification of phase competition among Fermi fluid, chiral spin liquid, and density waves.

Discovery of optimal further-range interaction for chiral spin correlations.

Mapping of the phase diagram in the $t/U$ and $V_1/U$ parameter space.

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.