Imaging tunable Luttinger liquid systems in van der Waals heterostructures

• 成果类型: Article
• 署名作者: Li, Hongyuan; Xiang, Ziyu; Wang, Tianle; Naik, Mit H.; Kim, Woochang; Nie, Jiahui; Li, Shiyu; Ge, Zhehao; He, Zehao; Ou, Yunbo; Banerjee, Rounak; Taniguchi, Takashi; Watanabe, Kenji; Tongay, Sefaattin; Zettl, Alex; Louie, Steven G.; Zaletel, Michael P.; 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; 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: Nature
• ISSN/ISSBN: 0028-5151
• DOI: 10.1038/s41586-024-07596-6
• 发表日期: 2024-07-25
• 关键词: spin-peierls transition; wigner crystal; ground-state; solitons

摘要

One-dimensional (1D) interacting electrons are often described as a Luttinger liquid1-4 having properties that are intrinsically different from those of Fermi liquids in higher dimensions5,6. In materials systems, 1D electrons exhibit exotic quantum phenomena that can be tuned by both intra- and inter-1D-chain electronic interactions, but their experimental characterization can be challenging. Here we demonstrate that layer-stacking domain walls (DWs) in van der Waals heterostructures form a broadly tunable Luttinger liquid system, including both isolated and coupled arrays. We have imaged the evolution of DW Luttinger liquids under different interaction regimes tuned by electron density using scanning tunnelling microscopy. Single DWs at low carrier density are highly susceptible to Wigner crystallization consistent with a spin-incoherent Luttinger liquid, whereas at intermediate densities dimerized Wigner crystals form because of an enhanced magneto-elastic coupling. Periodic arrays of DWs exhibit an interplay between intra- and inter-chain interactions that gives rise to new quantum phases. At low electron densities, inter-chain interactions are dominant and induce a 2D electron crystal composed of phased-locked 1D Wigner crystal in a staggered configuration. Increased electron density causes intra-chain fluctuation potentials to dominate, leading to an electronic smectic liquid crystal phase in which electrons are ordered with algebraical correlation decay along the chain direction but disordered between chains. Our work shows that layer-stacking DWs in 2D heterostructures provides opportunities to explore Luttinger liquid physics. Layer-stacking domain walls in van der Waals heterostructures form a broadly tunable Luttinger liquid system, including both isolated and coupled arrays.