发表机构
Fudan University; Westlake University; Westlake Institute for Advanced Study（复旦大学; 西湖大学; 西湖高等研究院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
在扭转双层MoS₂中观测到电子波梅兰丘克效应：低温下为巡游费米液体，升温时通过同位旋熵稳定局域广义维格纳晶体，揭示平带稳定磁构型的能力。
AI 中文摘要
过渡金属二硫属化物中的莫尔超晶格为探索强关联电子相（如广义维格纳晶体）提供了高度可调的平台。虽然这些晶态通常随热涨落增加而熔化，但波梅兰丘克效应的电子类比可通过同位旋熵在升高温度下稳定局域固态相。在此，我们报道在扭转角分别为4.1°和3.9°的AB堆叠扭转双层MoS$_2$中，于分数填充因子ν = 1/3和ν = 1/4处观测到电子波梅兰丘克效应。在超低温下，系统在这些分数填充处表现出高导电的巡游行为，这是可压缩费米液体基态的特征。加热时，系统表现出纵向电阻率的反直觉增加，标志着由同位旋熵驱动的向局域广义维格纳晶体态的转变。我们的发现凸显了扭转双层MoS$_2$中平带在稳定高度简并磁构型方面的独特能力，为低维关联系统的热力学相图提供了新见解。
英文摘要
Moire superlattices in transition metal dichalcogenides provide a highly tunable platform for exploring strongly correlated electronic phases, such as generalized Wigner crystals. While these crystalline states typically melt with increasing thermal fluctuations, an electronic analogue of the Pomeranchuk effect can stabilize the localized solid phase at elevated temperature through isospin entropy. Here, we report the observation of an electronic Pomeranchuk effect at the fractional filling factors of $ν= 1/3$ and $ν= 1/4$ in AB-stacked twisted bilayer MoS$_2$ with twist angles of 4.1$^\circ$ and 3.9$^\circ$, respectively. At ultra-low temperature, the system exhibits a highly conducting, itinerant behavior at these fractional fillings, characteristic of a compressible Fermi-liquid ground state. Upon heating, the system exhibits a counterintuitive increase in the longitudinal resistivity, signaling an isospin-entropy-driven transition into a localized generalized Wigner crystal state. Our findings highlight the unique capacity of flat bands in twisted bilayer MoS$_2$ for stabilizing highly degenerate magnetic configurations, offering new insights into the thermodynamic phase diagrams of low-dimensional correlated systems.
