标题： 利用光驱动集体电流激发：时依赖的$GW$方法 显示英文标题

标题： Driving collective current excitations using light: The time-dependent $GW$ approach

摘要： 电子在固体中的电子-电子相互作用会产生纵向集体电荷激发，称为等离子体激元，这些等离子体激元对应于电子密度响应函数中的共振。 在本研究中，我们证明了在非平衡条件下，电流-电流相互作用可以诱导非相互作用和相互作用电子系统中的一种新型集体激发，我们将其称为“库伦”。 通过考虑由电子电流产生的矢势与驱动它们的矢势之间的相互作用，我们构建了一个由矢势介导的相互作用电流系统。 我们展示了这会导致与电流-电流响应函数中的共振相对应的横向集体电流激发相关的准粒子的出现。 我们通过使用钠金属作为典型金属，在非平衡两时间GW方法中求解卡达诺夫-拜姆方程来解释电子-电子相互作用。 显示英文摘要

摘要： Electron-electron interactions in solids give rise to longitudinal collective charge excitations known as plasmons, which are observable corresponding to resonances in the density-density response function of the electrons. In this study, we demonstrate that current-current interactions can induce a novel type of collective excitation for systems of noninteracting and interacting electrons under nonequilibrium conditions, which we term as "curron". By taking into account the interaction between the vector potential generated by electronic currents and the vector potential driving them, we construct a system of interacting currents mediated by vector potentials. We show that this leads to the emergence of a quasiparticle associated with transverse collective current excitations, corresponding to resonances in the current-current response function. We account for electron-electron interaction by solving the Kadanoff-Baym equations within the non-equilibrium two-time GW approach using sodium metal as our prototypical metal.