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arXiv · 2210.15168

Magnetism and Quantum Melting in Moir\'e-Material Wigner Crystals

Nicolás Morales-Durán·Pawel Potasz·Allan H. MacDonald
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Abstract

Recent experiments have established that semiconductor-based moir\'e materials can host incompressible states at a series of fractional moir\'e-miniband fillings. These states have been identified as generalized Wigner crystals in which electrons localize on a subset of the available triangular-lattice moir\'e 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.

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Nicolás Morales-Durán, Pawel Potasz, Allan H. MacDonald. 2022-10-27. Magnetism and Quantum Melting in Moir\'e-Material Wigner Crystals. https://doi.org/10.1103/physrevb.107.235131

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