论文标题
带有本地和集体耗散过程的开放量子系统的相空间理论
Phase space theory for open quantum systems with local and collective dissipative processes
论文作者
论文摘要
在本文中，我们研究了由马尔可夫主方程与集体和非散发器给出的两级系统集合的驱动耗散量子动力学。利用模型中的置换对称性，我们采用相位空间方法来解决该方程的求解，以对角表示相对于某些广义旋转相干状态。值得注意的是，这允许在与希尔伯特空间维度无关的形式主义中插入平均场理论和有限系统大小。此外，在某些参数方程中，相应的准稳定性分布的演化方程类似于fokker-planck方程，可以通过随机计算有效地求解。然后，可以将动力学视为经典，从某种意义上说，两级系统之间没有纠缠。我们的结果暴露在激光理论的背景下，揭示，利用和促进技术，我们现在适用于当前的理论和实验兴趣问题。
In this article we investigate driven dissipative quantum dynamics of an ensemble of two-level systems given by a Markovian master equation with collective and non-collective dissipators. Exploiting the permutation symmetry in our model, we employ a phase space approach for the solution of this equation in terms of a diagonal representation with respect to certain generalized spin coherent states. Remarkably, this allows to interpolate between mean-field theory and finite system size in a formalism independent of Hilbert-space dimension. Moreover, in certain parameter regimes, the evolution equation for the corresponding quasiprobability distribution resembles a Fokker-Planck equation, which can be efficiently solved by stochastic calculus. Then, the dynamics can be seen as classical in the sense that no entanglement between the two-level systems is generated. Our results expose, utilize and promote techniques pioneered in the context of laser theory, which we now apply to problems of current theoretical and experimental interest.
