Quantum Correlation Dynamics Subjected to Quantum Reset-Driven Environment
Institute for Advanced Studies in Basic Sciences (IASBS)（基础科学高等研究院）；Institute for Research in Fundamental Sciences (IPM)（基础科学研究院）；University of Toronto（多伦多大学）；Beijing Institute of Mathematical Sciences and Applications (BIMSA)（北京应用数学与交叉科学研究中心）
R. Jafari, Ali Asadian, Mehdi Biderang, Alireza Akbari
我们研究两个纠缠量子比特与一个横向场异斯汀链相互作用，该链作为其环境。环境在时间上线性驱动穿过其量子临界点（QCPs），并在演化过程中受到量子重置（QR）的影响，即在随机时间将其返回到初始状态。我们研究这种环境自旋链的量子重置如何改变量子比特之间的纠缠和量子分歧的动力学。我们的结果表明，在强耦合 regime 中，纠缠和分歧在由异斯汀 QCPs 界定的区间内表现出明显的复兴，但随着 QR 率的增加，这些复兴减弱。相反，弱耦合导致量子相关性单调减少。数值上，我们发现纠缠度的复兴峰值衰减并随 QR 率指数级减少，而量子分歧则没有明显缩放行为。在无 QR 的弱耦合 regime 中，当驱动场穿过第二个 QCP 时，相关性单调衰减。然而，当应用 QR 时，纠缠和分歧都会经历振荡抑制，振荡周期随着 QR 率或斜率时间尺度的减少而增加。
英文摘要：
We study two central qubits interacting with a transverse-field Ising chain that serves as their environment. The environment is driven linearly in time across its quantum critical points (QCPs) and, during the evolution, is subjected to quantum reset (QR), where it is returned at random times to its initial state. We investigate how such QR of the environmental spin chain modifies the dynamics of entanglement and quantum discord between the qubits. Our results show that in the strong-coupling regime, entanglement and discord exhibit pronounced revivals within the interval bounded by the Ising QCPs, but these revivals diminish as the QR rate increases. In contrast, weak coupling leads to a monotonic reduction of quantum correlations. Numerically, we find that the revival peaks of concurrence decay and scale exponentially with the QR rate, while quantum discord shows no clear scaling behavior. In the weak-coupling regime without QR, the correlations decay monotonically as the driven field crosses the second QCP. When QR is applied, however, both entanglement and discord undergo oscillatory suppression, with the oscillation period increasing as either the QR rate or the ramp time scale is reduced.
We study a non-interacting quantum particle, moving on a one-dimensional lattice, which is subjected to repetitive measurements. We investigate the consequence when such motion is interrupted and restarted from the same initial configuration, known as the quantum resetting problem. We show that such systems can be described by the time evolution under certain time-dependent non-Hermitian Hamiltonians. We construct two such Hamiltonians and compare the results with the exact dynamics. Using this effective non-Hermitian description we evaluate the timescale of the survival probability as well as…
Generating pairwise entanglement in periodically driven quantum spin chains with stochastic resetting
School of Physical Sciences, Indian Association for the Cultivation of Science（印度科学培养协会物理科学学院）；International Centre for Theoretical Sciences, Tata Institute of Fundamental Research（塔塔基础研究所国际理论科学中心）；LPTMS, CNRS, Univ. Paris-Sud, Université Paris-Saclay（巴黎南大学、萨克雷大学，法国国家科学研究中心理论与物质物理实验室）
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Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California（南加州大学明何电机工程学院）；Department of Physics and Astronomy, University of Southern California（南加州大学物理与天文学系）
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Exact nonequilibrium steady states of boundary driven circuit with XYZ gates
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所凝聚态物理国家实验室）；Faculty of Mathematics and Physics, University of Ljubljana（卢布尔雅那大学数学与物理学院）；Institute of Mathematics, Physics and Mechanics（数学、物理和力学研究所）；Department of Physics, University of Wuppertal（伍珀塔尔大学物理系）
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