论文标题
在扭曲的双双层石墨烯中相关的电子孔状态
Correlated electron-hole State in Twisted Double Bilayer Graphene
论文作者
论文摘要
当将角度扭转到1°附近的角度时，石墨烯多层通过托管可托管栅极调节的强烈相关状态（包括绝缘体，超导体和异常磁铁）提供了一个新的电子相关物理窗口。在这里，我们报告了一个新的家族成员，密度波状态，在双重双层石墨烯中扭曲为2.37°。莫伊尔（Moiré）以这个角度保留了许多孤立的双层特征，从而使他们的双层投影可以通过大门单独控制。我们使用此特性在狭窄的孤立电子和具有良好嵌套特性的孔带之间产生一个能量重叠。我们的测量结果揭示了与密度波状态相一致的重构费米表面的有序状态，以相等的电子和孔密度。可以在不引入化学掺杂剂的情况下对这些状态进行调整，从而为密度波的新基本研究及其与超导性和其他类型的秩序相互作用打开了大门，这是量子物质物理学的核心问题。
When twisted to angles near 1°, graphene multilayers provide a new window on electron correlation physics by hosting gate-tuneable strongly-correlated states, including insulators, superconductors, and unusual magnets. Here we report the discovery of a new member of the family, density-wave states, in double bilayer graphene twisted to 2.37°. At this angle the moiré states retain much of their isolated bilayer character, allowing their bilayer projections to be separately controlled by gates. We use this property to generate an energetic overlap between narrow isolated electron and hole bands with good nesting properties. Our measurements reveal the formation of ordered states with reconstructed Fermi surfaces, consistent with density-wave states, for equal electron and hole densities. These states can be tuned without introducing chemical dopants, thus opening the door to a new class of fundamental studies of density-waves and their interplay with superconductivity and other types of order, a central issue in quantum matter physics.
