Theory of ultrafast nonequilibrium dynamics in d -wave superconductors
Theory of ultrafast nonequilibrium dynamics in d -wave superconductors
复制标题
DOI：
10.1103/physrevb.77.180509
复制
发表时间：
2007-07
影响因子：
3.7
通讯作者：
J. Unterhinninghofen;D. Manske;A. Knorr
中科院分区：
文献类型：
--
作者：
J. Unterhinninghofen;D. Manske;A. Knorr
我们用密度矩阵理论从微观角度计算非常规超导体的超快动力学。我们计算了d波序参量的光电导率和泵浦-探测光谱随时间的演化。在光谱中可以区分出三个区域。在低光子能量下的德鲁德响应是迄今为止实验测量到的唯一一个。在更高的能量，我们预测两个制度：对断裂峰，这是减少库珀对被打破了由激发脉冲;和抑制以上的对断裂峰由于非平衡准粒子。在此基础上，我们考虑了电子-声子耦合的影响，导出了迄今为止被广泛应用的速率方程。
We use density-matrix theory to calculate the ultrafast dynamics of unconventional superconductors from a microscopic viewpoint. We calculate the time evolution of the optical conductivity as well as pump-probe spectra for a d-wave order parameter. Three regimes can be distinguished in the spectra. The Drude response at low photon energies is the only one of those which has been measured experimentally so far. At higher energies, we predict two more regimes: the pair-breaking peak, which is reduced as Cooper-pairs are broken up by the exciting pulse; and a suppression above the pair-breaking peak due to nonequilibrium quasiparticles. Furthermore, we consider the influence of the electron-phonon coupling, and derive rate equations which have been widely used so far.