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This content will become publicly available on July 5, 2025

Title: Wigner molecular crystals from multielectron moiré artificial atoms

Semiconductor moiré superlattices provide a versatile platform to engineer quantum solids composed of artificial atoms on moiré sites. Previous studies have mostly focused on the simplest correlated quantum solid—the Fermi-Hubbard model—in which intra-atom interactions are simplified to a single onsite repulsion energyU. Here we report the experimental observation of Wigner molecular crystals emerging from multielectron artificial atoms in twisted bilayer tungsten disulfide moiré superlattices. Using scanning tunneling microscopy, we demonstrate that Wigner molecules appear in multielectron artificial atoms when Coulomb interactions dominate. The array of Wigner molecules observed in a moiré superlattice comprises a crystalline phase of electrons: the Wigner molecular crystal, which is shown to be highly tunable through mechanical strain, moiré period, and carrier charge type.

 
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Award ID(s):
2221750
NSF-PAR ID:
10534445
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
385
Issue:
6704
ISSN:
0036-8075
Page Range / eLocation ID:
86 to 91
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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