论文标题
量子混乱，平衡和控制在极短的旋转链中
Quantum chaos, equilibration and control in extremely short spin chains
论文作者
论文摘要
通常将开放量子系统的环境建模为大型多体量子系统。但是，当孤立的量子系统本身是一个多体量子系统时，为了产生内部平衡而必须有多大和复杂的问题是文献中的一个开放关键点。在这项工作中，通过监测单个旋转的纯度降解的平衡程度，我们能够感觉到与之耦合的通用自旋链的混乱行为。相当值得注意的是，即使在由三个旋转组成的极短的旋转链中，这也可以保留，在这里我们还可以将整个整合到混乱过渡中。最后，我们讨论了对量子控制实验的含义，并表明量子混乱在达到最佳的控制程度上，即使在小链中也是如此。
The environment of an open quantum system is usually modelled as a large many-body quantum system. However, when an isolated quantum system itself is a many-body quantum system, the question of how large and complex it must be in order to generate internal equilibration is an open key-point in the literature. In this work, by monitoring the degree of equilibration of a single spin through its purity degradation, we are able to sense the chaotic behaviour of the generic spin chain to which it is coupled. Quite remarkably, this holds even in the case of extremely short spin chains composed of three spins, where we can also reproduce the whole integrable to chaos transition. Finally, we discuss implications on quantum control experiments and show that quantum chaos reigns over the best degree of control achieved, even in small chains.
