论文标题
在因果秩序的叠加下量子行走
Quantum walks under superposition of causal order
论文作者
论文摘要
我们设置了可以将因果秩序叠加到量子步行中的标准。特别是，我们表明，在“量子开关”的作用下，只有周期性的量子步行或至少有一种疾病的因果关系叠加的量子。我们以两个周期离散时间量子步行的简单示例来体现我们的结果。特别是，我们观察到，周期性量子步道表现出与减少的硬币态动力学有关的因果不对称：一个时间顺序的动力学比另一个动力学更无非对称。我们还注意到，由于因果关系不确定而导致的硬币状态的非马克维亚性倾向于与硬币状态的特定时间顺序的动力学相匹配。我们通过数值模拟来证实结果。
We set the criteria under which superposition of causal order can be incorporated in to quantum walks. In particular, we show that only periodic quantum walks or those with at least one disorder exhibit Superposition of causal order under the action of `quantum switch'. We exemplify our results with a simple example of two-period discrete-time quantum walks. In particular, we observe that periodic quantum walks exhibit causal asymmetry pertaining to the dynamics of the reduced coin state: the dynamics are more non-Markovian for one temporal order than the other. We also note that the non-Markovianity of the reduced coin state due to indefiniteness in causal order tends to match the dynamics of a particular temporal order of the coin state. We substantiate our results with numerical simulations.
