论文标题
淬灭超导阶段后的电子和波动动力学
Electronic and fluctuation dynamics following a quench to the superconducting phase
论文作者
论文摘要
我们研究了从无序阶段到有序方案的淬灭后，我们研究了有吸引力的三维哈伯德模型中超导波动的动力学。尽管长期演化从具有不稳定电位的耗散时间依赖性的金茨堡 - 兰道模型来理解，但由于配对波动和电子准粒子的不可分割动力学，早期的时间更加苛刻。我们使用时间依赖性波动交换近似的模拟在同一基础上处理两个自由度，并揭示了非热电子体制，从而导致波动的非单调生长。该特征并未直接从金茨堡 - 兰道理论中捕获，但是除了电子的热化时间以外，仍然可以观察到。我们进一步探讨了顺序参数波动的生长如何导致电子频谱中伪空隙的开放，并将Andreev反射识别为间隙开放背后的主要机制。
We investigate the dynamics of superconducting fluctuations in the attractive three-dimensional Hubbard model after a quench from the disordered phase to the ordered regime. While the long time evolution is well understood in terms of dissipative time-dependent Ginzburg-Landau models with unstable potentials, early times are more demanding due to the inseparable dynamics of the pairing fluctuations and the electronic quasiparticles. Our simulation using the time-dependent fluctuation exchange approximation treat both degrees of freedom on the same footing and reveal a non-thermal electronic regime causing a non-monotonous growth of the fluctuations. This feature is not directly captured from the Ginzburg-Landau theory, but nevertheless remains observable beyond the thermalization time of the electrons. We further explore how the growth of the order parameter fluctuations leads to an opening of a pseudo-gap in the electronic spectrum, and identify Andreev reflections as the dominant mechanism behind the gap opening.
