Transition metal dichalcogenide-based moire superlattices exhibit very strong electron-electron correlations, thus giving rise to strongly correlated quantum phenomena such as generalized Wigner crystal states1-8. Theoretical studies predict that unusual quasiparticle excitations across the correlated gap between upper and lower Hubbard bands can arise due to long-range Coulomb interactions in generalized Wigner crystal states7,9. Here we describe a new scanning single-electron charging (SSEC) spectroscopy technique with nanometer spatial resolution and single-electron charge resolution that enables us to directly image electron and hole wavefunctions and to determine the thermodynamic gap of generalized Wigner crystal states in twisted WS2 moire heterostructures. High-resolution SSEC spectroscopy was achieved by combining scanning tunneling microscopy (STM) with a monolayer graphene sensing layer, thus enabling the generation of individual electron and hole quasiparticles in generalized Wigner crystals. We show that electron and hole quasiparticles have complementary wavefunction distributions and that thermodynamic gaps of order 50meV exist for the 1/3 and 2/3 generalized Wigner crystal states.

中文翻译：

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映射广义维格纳晶体中的电荷激发

基于过渡金属二硫属化物的莫尔超晶格表现出非常强的电子-电子相关性，因此产生了强相关的量子现象，例如广义 Wigner 晶态 1-8。理论研究预测，由于广义 Wigner 晶态 7,9 中的长程库仑相互作用，可能会出现跨越上下哈伯德带之间相关间隙的异常准粒子激发。在这里，我们描述了一种新的扫描单电子充电 (SSEC) 光谱技术，具有纳米空间分辨率和单电子电荷分辨率，使我们能够直接成像电子和空穴波函数并确定扭曲 WS2 波纹中广义 Wigner 晶态的热力学间隙异质结构。高分辨率 SSEC 光谱是通过将扫描隧道显微镜 (STM) 与单层石墨烯传感层相结合来实现的，从而能够在广义 Wigner 晶体中生成单个电子和空穴准粒子。我们表明电子和空穴准粒子具有互补的波函数分布，并且对于 1/3 和 2/3 广义 Wigner 晶态存在 50meV 量级的热力学间隙。