Hänggi Peter, Ingold Gert-Ludwig
Institut für Physik, Universität Augsburg, 86135 Augsburg, Germany.
Chaos. 2005 Jun;15(2):26105. doi: 10.1063/1.1853631.
With this work we elaborate on the physics of quantum noise in thermal equilibrium and in stationary nonequilibrium. Starting out from the celebrated quantum fluctuation-dissipation theorem we discuss some important consequences that must hold for open, dissipative quantum systems in thermal equilibrium. The issue of quantum dissipation is exemplified with the fundamental problem of a damped harmonic quantum oscillator. The role of quantum fluctuations is discussed in the context of both, the nonlinear generalized quantum Langevin equation and the path integral approach. We discuss the consequences of the time-reversal symmetry for an open dissipative quantum dynamics and, furthermore, point to a series of subtleties and possible pitfalls. The path integral methodology is applied to the decay of metastable states assisted by quantum Brownian noise.
通过这项工作，我们详细阐述了热平衡和稳态非平衡状态下量子噪声的物理原理。从著名的量子涨落耗散定理出发，我们讨论了热平衡下开放、耗散量子系统必须满足的一些重要结论。量子耗散问题以阻尼量子简谐振子的基本问题为例进行说明。在非线性广义量子朗之万方程和路径积分方法这两种背景下讨论了量子涨落的作用。我们讨论了时间反演对称性对开放耗散量子动力学的影响，此外，还指出了一系列微妙之处和可能存在的陷阱。路径积分方法被应用于量子布朗噪声辅助下亚稳态的衰变。
