论文标题
三维的流体动力声音和等离子体
Hydrodynamic sound and plasmons in three dimensions
论文作者
论文摘要
在Lucas和Das Sarma的最新论文中[物理评论B 97，115449（2018）]，在流体动力学制度中考虑了2D金属集体模式的可解决模型。在当前的工作中，我们将流体动力学理论推广到3D金属，以强耦合量子库仑等离子体的声音模式可以显式。感兴趣的具体理论问题是，在存在远距离库仑相互作用的情况下，通常线性分散流体动力声音模式与众所周知的glaped 3D等离子体集体模式有关。我们分析表明，无碰撞状态中的零声音和流体动力区域中的第一个声音在3D中都变得巨大，由于远距离的库仑相互作用而获得有限的间隙，而它们的阻尼速率在动量中变得二次。我们还讨论了其他类型的远程潜力，其中声音模式的分散会相应地修改。总体上结果是，在存在远程库仑相互作用的情况下，前阶等离子频率始终由领先的流体动力学模式给出，但是次要领导的分散校正校正在流体动力和无碰撞状态方面有所不同。
In a recent paper by Lucas and Das Sarma [Physical Review B 97, 115449 (2018)], a solvable model of collective modes in 2D metals was considered in the hydrodynamic regime. In the current work, we generalize the hydrodynamic theory to 3D metals for which the calculation of sound modes in a strongly-coupled quantum Coulomb plasma can be made explicit. The specific theoretical question of interest is how the usual linearly dispersing hydrodynamic sound mode relates to the well-known gapped 3D plasmon collective mode in the presence of long-range Coulomb interaction. We show analytically that both the zero sound in the collisionless regime and the first sound in the hydrodynamic region become massive in 3D, acquiring a finite gap because of the long-range Coulomb interaction, while their damping rates become quadratic in momentum. We also discuss other types of long-range potential, where the dispersion of sound modes is modified accordingly. The general result is that the leading order hydrodynamic sound mode is always given by the leading-order plasmon frequency in the presence of long-range Coulomb interaction, but the next-to-leading-order dispersion corrections differ in hydrodynamic and colllisionless regimes.
