论文标题
石墨烯中电子的异常热扩散
Anomalous thermodiffusion of electrons in graphene
论文作者
论文摘要
我们揭示了相对于理想的自由电子气体模型的普遍接受的图片，固体中电子热扩散的急剧脱落。特别是，我们表明与晶格和杂质的相互作用，结合了电子分散关系的强大依赖性，导致了反直觉的扩散行为，我们通过比较单层二维电子（2DEG）和石墨烯来识别它们。当受到温度梯度$ \ nabla t $的约束时，无质量的狄拉克电子在石墨烯中表现出异常的行为，电子的行为与沿$ \ nabla t $移动并在热区域中累积的电子相比，与寄生虫分散的2密度电子扩散相反，与寄生虫分散相比，净动作与$ \ nabla $ \ nabla nabla nabla nable teple n everled nevern cypan cyper nat verver n hotever nat vaster nat vaster contect nate nat venter nat vaster contect。这些发现对于理解新兴材料中的空间电子动力学至关重要，建立了与在不均匀温度条件下与电子系统有关的其他物理分支的密切关系。
We reveal a dramatic departure of electron thermodiffusion in solids relative to the commonly accepted picture of the ideal free-electron gas model. In particular, we show that the interaction with the lattice and impurities, combined with a strong material dependence of the electron dispersion relation, leads to counterintuitive diffusion behavior, which we identify by comparing a single-layer two-dimensional electron gas (2DEG) and graphene. When subject to a temperature gradient $\nabla T$, thermodiffusion of massless Dirac electrons in graphene exhibits an anomalous behavior with electrons moving along $\nabla T$ and accumulating in hot regions, in contrast to normal electron diffusion in a 2DEG with parabolic dispersion, where net motion against $\nabla T$ is observed, accompanied by electron depletion in hot regions. These findings have fundamentally importance for the understanding of the spatial electron dynamics in emerging material, establishing close relations with other branches of physics dealing with electron systems under nonuniform temperature conditions.
