Department of Optics, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
School of Physics, Trinity College Dublin, Dublin 2, Ireland.
Phys Rev Lett. 2018 Aug 17;121(7):070401. doi: 10.1103/PhysRevLett.121.070401.
We identify sufficient conditions on the structure of the interaction Hamiltonian between a two-level quantum system and a thermal bath that, without any external drive or coherent measurement, guarantee the generation of steady-state coherences (SSC). The SSC obtained this way, remarkably, turn out to be independent of the initial state of the system, which could therefore be taken as initially incoherent. We characterize in detail this phenomenon, first analytically in the weak coupling regime for two paradigmatic models, and then numerically in more complex systems without any assumption on the coupling strength. In all of these cases, we find that SSC become increasingly significant as the bath is cooled down. These results can be directly verified in many experimental platforms.
我们确定了在两能级量子系统与热浴之间相互作用哈密顿量的结构上的充分条件，这些条件无需任何外部驱动或相干测量，就能保证稳态相干（SSC）的产生。以这种方式获得的 SSC 非常显著，与系统的初始状态无关，因此系统初始可以是不相干的。我们详细地描述了这一现象，首先在两个典型模型的弱耦合情况下进行了分析，然后在没有对耦合强度的任何假设的情况下在更复杂的系统中进行了数值模拟。在所有这些情况下，我们发现随着浴的冷却，SSC 变得越来越显著。这些结果可以在许多实验平台上直接验证。
