We investigate the dynamics of a two-level system in the presence of an overall environment composed of two layers. The first layer is just one single-mode cavity that decays to a memoryless reservoir while the second layer is two coupled single-mode cavities that decay to memoryless or memory-keeping reservoirs. We show that, in the weak-coupling regime between the qubit and the first-layer environment, the speed of evolution for the system can be controlled to a speeded-up or speeded-down process by manipulating the coupling strength in a double-layer environment. In particular, we find that multiple dynamics transitions from a not-speeded-up evolution to speeded-up evolution can be realized for the system by increasing the coupling strength in the second-layer environment. These results hold independently of the nature of the reservoirs in the second-layer environment.

中文翻译：

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双层环境中的量子演化速度

在存在由两层组成的整体环境的情况下，我们研究了两级系统的动力学。第一层只是一个衰减到无记忆存储池的单模腔，而第二层是两个耦合的衰减到无记忆存储池的单模腔。我们表明，在量子位和第一层环境之间的弱耦合状态下，可以通过操纵双层中的耦合强度将系统的演化速度控制为加速或减速过程。环境。特别是，我们发现，通过增加第二层环境中的耦合强度，可以实现系统从未加速发展到加速发展的多个动力学过渡。