论文标题
狄拉克电子流体中电子孔碰撞的粘度增强
Viscosity Enhancement by Electron-Hole Collisions in Dirac Electron Fluid
论文作者
论文摘要
固体中流体动力传输的复兴为研究电子的集体运动提供了一个新的窗口，在该窗口中，电子的行为就像类似于经典液体的粘性流体。直到近年来才意识到这种外来状态的实验性观察，并且持续的追求是扩大电子流体中的流体动力效应。在这里，我们从微观的角度研究了石墨烯中狄拉克电子流体的流体动力学特性，并阐明了一种增强电子流体力学的新方法。特别是，我们提供了有力的证据表明，频繁的电子孔碰撞可以通过三个不同的方面来增强狄拉克电子的剪切粘度：通过无序来促进迪拉克点周围的电子和孔，通过外部磁场创建电子孔共享零孔Landau水平，并通过动态变形来诱导电子孔孔。我们还研究了与几何拓扑密切相关的霍尔粘度，并且表现出类似于霍尔电导率的量子行为。因此，我们的工作证明了石墨烯中流体力学电子产品的外来景观，并提出了与实验相关的响应，以量化电子粘度的影响。
Rejuvenation of hydrodynamic transport in solids provides a new window to study collective motion of electrons, where electrons behave like a viscous fluid akin to classical liquids. Experimental observations of such exotic states have not been realized until recent years, and an on-going quest is to amplify the hydrodynamic effect in electron fluids. Here we investigate the hydrodynamic properties of Dirac electron fluid in graphene from a microscopic viewpoint, and elucidate a novel way to enhance electron hydrodynamics. In particular, we present strong evidence that the shear viscosity of Dirac electrons can be enhanced by frequent electron-hole collisions, through three distinct aspects: promoting electrons and holes around the Dirac point by disorder, creating electron-hole shared zeroth Landau level by external magnetic field, and inducing electron-hole excitations by dynamic deformation. We also study Hall viscosity, which is closely related to the geometric topology and exhibits quantum behavior analogous to Hall conductivity. Therefore, our work demonstrates the exotic landscape of hydrodynamic electronics in graphene, and presents experimentally relevant responses to quantify the effects of electronic viscosity.
