Magnetism and Quantum Melting in Moiré-Material Wigner Crystals

Abstract

Recent experiments have established that semiconductor-based moiré materials can host incompressible states at a series of fractional moiré-miniband fillings. These states have been identified as generalized Wigner crystals in which electrons localize on a subset of the available triangular-lattice moiré superlattice sites. In this article, we use momentum-space exact diagonalization to investigate the many-body ground state evolution at rational fillings from the weak-hopping classical lattice gas limit, in which only spin degrees-of-freedom are active at low energies, to the strong-hopping metallic regime where the Wigner crystals melt. We specifically address the nature of the magnetic ground states of the generalized Wigner crystals at fillings $\nu$ = 1/3 and $\nu$ = 2/3.

12 pages, 8 figures

References in corpus (3)

• Frustrated magnetic interactions in a Wigner-Mott insulator
• Dielectric catastrophe at the Mott and Wigner transitions in a moiré superlattice
• Continuous Mott transition in moiré semiconductors: role of long-wavelength inhomogeneities

Cited by in corpus (19)

• Frustrated magnetic interactions in a Wigner-Mott insulator
• Topological electronic crystals in twisted bilayer-trilayer graphene
• Quantum Wigner molecules in moiré materials
• Quantum Melting of Generalized Wigner Crystals in Transition Metal Dichalcogenide Moiré Systems
• Probing magnetism in moiré heterostructures with quantum twisting microscopes
• Competing Generalized Wigner Crystal States in Moiré Heterostructures
• Charge and spin properties of a generalized Wigner crystal realized in the moiré WSe${}_2$/WS${}_2$ heterobilayer
• Exciton interacting with a moiré lattice: Polarons, strings, and optical probing of spin correlations
• Twistronics and moiré superlattice physics in 2D transition metal dichalcogenides
• Quantum melting of generalized electron crystal in twisted bilayer MoSe2
• Itinerant ferromagnetism in transition metal dichalcogenides moiré superlattices
• Continuous Wigner-Mott transition at $\nu =1/5$
• Magnetic properties of moiré quantum dot arrays
• Origin and stability of generalized Wigner crystallinity in triangular moiré systems
• Moiré excitons in generalized Wigner crystals
• Spin-orbital magnetism in moiré Wigner molecules
• Magnetism from multiparticle ring exchange in moiré Wigner crystals
• Quantum melting a Wigner crystal into Hall liquids
• Electronic phonon-induced magnetism in moiré Mott-Wigner crystals