发表机构
Center for Theoretical Physics, Polish Academy of Sciences; Nordita, Stockholm University and KTH Royal Institute of Technology; Institute of Theoretical Physics, University of Warsaw; School of Mathematics and Physics, The University of Queensland（波兰科学院理论物理中心; 诺迪塔，斯德哥尔摩大学和皇家理工学院; 华沙大学理论物理研究所; 昆士兰大学数学与物理学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究定义多时间量子过程的相干性，证明访问中间时间可揭示成对信道中不存在的相干性，并在超导处理器上通过伊辛模型验证了该多时间相干性。
AI 中文摘要
开放量子系统中的非经典动力学可能隐藏在对标准态和信道测试不可见的时间关联中。我们为多时间量子过程定义了相干性，并表明访问中间时间可以揭示所有相应成对信道中不存在的相干性。非相干过程是去相位在所有输入和输出空间上的不动点，其相干性通过相对熵量化。作为原理验证，我们使用一个伊辛模型，其中所有三个成对信道都是非相干的，而完整的三时间过程保持相干。我们在超导量子处理器上通过相干性见证和完整过程层析成像观测到这种多时间相干性。
英文摘要
Non-classical dynamics in open quantum systems can be hidden in temporal correlations that are invisible to standard state- and channel-based tests. We define coherence for multi-time quantum processes and show that access to intermediate times can reveal coherence absent from all corresponding pairwise channels. Incoherent processes are fixed points of dephasing on all input and output spaces, and their coherence is quantified by relative entropy. As a proof of principle, we use an Ising model in which all three pairwise channels are incoherent while the full three-time process remains coherent. We observe this multi-time coherence on a superconducting quantum processor using a coherence witness and full process tomography.
Comments7+5 pages, 4+3 figures, 1 table
