Wigner molecular crystals from multielectron moire artificial atoms

• 成果类型: Article
• 署名作者: Li, Hongyuan; Xiang, Ziyu; Reddy, Aidan P.; Devakul, Trithep; Sailus, Renee; Banerjee, Rounak; Taniguchi, Takashi; Watanabe, Kenji; Tongay, Sefaattin; Zettl, Alex; Fu, Liang; Crommie, Michael F.; Wang, Feng
• 署名单位: University of California System; University of California Berkeley; University of California System; University of California Berkeley; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; Massachusetts Institute of Technology (MIT); Arizona State University; Arizona State University-Tempe; National Institute for Materials Science; National Institute for Materials Science; University of California System; University of California Berkeley; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11817
• DOI: 10.1126/science.adk1348
• 发表日期: 2024-07-05
• 页码: 86-91
• 关键词: quantum dots; symmetry-breaking; insulator; electrons; BEHAVIOR; single; STATES; mott

摘要

Semiconductor moire superlattices provide a versatile platform to engineer quantum solids composed of artificial atoms on moire 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 energy U. Here we report the experimental observation of Wigner molecular crystals emerging from multielectron artificial atoms in twisted bilayer tungsten disulfide moire 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 moire superlattice comprises a crystalline phase of electrons: the Wigner molecular crystal, which is shown to be highly tunable through mechanical strain, moire period, and carrier charge type.