It has been well established that the evolution of an isolated quantum system can appear as undergoing pure dephasing to an observer using an imperfect clock. In this work, we apply this theory to the transport phenomenon in open quantum systems. Starting with a system intrinsically undergoing nonunitary evolution in ideal time, we consider the effect of a realistic clock that approaches Gaussian distribution in the long-time limit. For quantum transport, it eventually leads to a general physical prediction: a stable probability current in a quantum transport system must be robust against any transformation that conforms with a simple formula given by an ideal Gaussian stationary clock. This understanding of quantum transport is demonstrated numerically in a topological insulator, where it also explains the robustness of the quantum Hall response against pure dephasing.

中文翻译：

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现实时钟的有效去相干性：一般理论及其在拓扑绝缘子中的应用

众所周知，使用不完善的时钟，孤立的量子系统的演化可以表现为对观察者进行纯移相。在这项工作中，我们将此理论应用于开放量子系统中的传输现象。从一个系统在理想时间内本质上经历非单位演化的系统开始，我们考虑一个在长时限内逼近高斯分布的现实时钟的影响。对于量子传输，它最终会导致一个一般的物理预测：量子传输系统中的稳定概率电流必须对任何与理想高斯平稳时钟给出的简单公式一致的变换都具有鲁棒性。在拓扑绝缘体中以数字方式证明了对量子传输的这种理解，