Abstract：
Manipulating the flat band degeneracy and thus getting the correlated insulating phases has been an ideal thread for realizing the exotic quantum phenomenon in the moiré system. To achieve this goal, the delicately tuned twist angle and a substantial displacement field (D) are rigorously requested. Here, we report our scanning tunneling microscope (STM) work on reaching these correlated insulating states in twisted monolayer-bilayer graphene through a decorated tip. It acts as a local top gate, leading to an enhanced local D, and enables us to fully lift the 8-fold degeneracy of the flat bands. With the aid of this technique, we further expand the correlated insulating states into a more tolerant twist angle that is down to 0.92°. Moreover, the correlated insulating phases in the hole-doping regime are realized. Our tip decoration method allows us to integrate the STM study with the high displacement field for the correlated phases in the twisted moiré systems.
摘要：
操纵平带简并从而获得相关的绝缘相一直是在莫尔系统中实现奇异量子现象的理想途径。为了实现这一目标,严格要求微调的扭转角和大量的位移场（D）。这里,我们报告了我们的扫描隧道显微镜（STM）通过装饰尖端在扭曲的单层双层石墨烯中达到这些相关的绝缘状态的工作。它充当当地的顶门，导致增强的局部D，并使我们能够完全解除平带的8倍简并性。借助这种技术，我们进一步将相关绝缘状态扩展为更宽容的扭曲角，该扭曲角降至0.92°。此外，实现了空穴掺杂体系中的相关绝缘相。我们的尖端装饰方法使我们能够将STM研究与扭曲莫尔系统中相关相的高位移场集成在一起。
