The strong electron interactions in the minibands formed in moiré superlattices of van der Waals materials, such as twisted graphene and transition metal dichalcogenides, make such systems a fascinating platform with which to study strongly correlated states^{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19}. In most systems, the correlated states appear when the moiré lattice is filled by an integer number of electrons per moiré unit cell. Recently, correlated states at fractional fillings of 1/3 and 2/3 holes per moiré unit cell have been reported in the WS₂/WSe₂ hetero-bilayer, hinting at the long-range nature of the electron interaction¹⁶. Here we observe a series of correlated insulating states at fractional fillings of the moiré minibands on both electron- and hole-doped sides in angle-aligned WS₂/WSe₂ hetero-bilayers, with certain states persisting at temperatures up to 120 K. Simulations reveal that these insulating states correspond to ordering of electrons in the moiré lattice with a periodicity much larger than the moiré unit cell, indicating a surprisingly strong and long-range interaction beyond the nearest neighbours.

在范德华材料的莫尔超晶格中形成的微带中的强电子相互作用，例如扭曲的石墨烯和过渡金属二硫化物，使此类系统成为研究强相关态的迷人平台^{1,2,3,4,5,6 ,7,8,9,10,11,12,13,14,15,16,17,18,19}。在大多数系统中，当莫尔晶格被每个莫尔晶胞的整数个电子填充时，就会出现相关状态。_{最近，在 WS 2} /WSe ₂异质双层中报道了每个莫尔晶胞 1/3 和 2/3 孔的分数填充的相关状态，这暗示了电子相互作用的长程性质¹⁶. _{在这里，我们在角度对齐的 WS 2} /WSe ₂异质双层中观察到在电子和空穴掺杂侧的莫尔微带的分数填充处的一系列相关绝缘状态，某些状态在高达 120 K 的温度下持续存在。模拟揭示了这些绝缘状态对应于莫尔晶格中电子的排序，其周期性远大于莫尔晶胞，表明在最近邻之外存在令人惊讶的强和长程相互作用。