近日，西安交通大学王欣团队研究了准周期非线性波导中的超相关衰减：从马尔可夫到非马尔可夫的转变。2025年7月24日出版的《物理评论A》杂志发表了这项成果。

迁移边缘（MEs）是无序量子系统中分离局域态和扩展态的关键边界，对输运性质和相变有重要影响。虽然微粒子在单光子系统中很好地理解，但它们在多体环境中的表现仍然是一个活跃的研究领域。

研究组分析了具有准周期势调制光子-光子相互作用的一维玻色-哈伯德链，有效地创建了马赛克晶格。他们确定了双光子子空间中双玻态（即由强相互作用产生的束缚光子对）的微粒子。该解析解和数值模拟证实了这些微粒子的存在，将单光子微粒子理论扩展到双光子体系。此外，研究组还分析了耦合到波导上的两个发射器的动力学，使超相关光子对能够发射到波导中。

研究结果表明，与扩展态的耦合导致了以指数超相关衰减为特征的马尔可夫动力学，而与局域态的耦合产生了以抑制衰减和持续振荡为特征的非马尔可夫动力学。从马尔可夫行为到非马尔可夫行为的转变发生在doublons的MEs附近。最后，研究组提出了一个以超导电路为主题的可行实验实现，为观察量子系统中相互作用和无序之间的相互作用提供了一个平台。

附：英文原文

Title: Supercorrelated decay in a quasiperiodic nonlinear waveguide: From Markovian to non-Markovian transitions

Author: Jia-Qi Li, Tian-Yu Zhou, Xin Wang

Issue&Volume: 2025/07/24

Abstract: Mobility edges (MEs) are critical boundaries in disordered quantum systems that separate localized from extended states, significantly affecting transport properties and phase transitions. Although MEs are well-understood in single-photon systems, their manifestation in many-body contexts remains an active area of research. In this work, we investigate a one-dimensional Bose-Hubbard chain with a quasiperiodic potential modulating photon-photon interactions, effectively creating a mosaic lattice. We identify MEs for doublon states (i.e, bound photon pairs resulting from strong interactions) within the two-photon subspace. Our analytical solutions and numerical simulations confirm the existence of these MEs, extending single-photon MEs theories to the two-photon regime. Additionally, we analyze the dynamics of two emitters coupled to the waveguide, enabling the emission of supercorrelated photon pairs into the waveguide. Our findings reveal that coupling to extended states results in Markovian dynamics, characterized by exponentially supercorrelated decay, while coupling to localized states gives rise to non-Markovian dynamics, marked by suppressed decay and persistent oscillations. Here, a transition from Markovian to non-Markovian behavior occurs around the MEs of the doublons. Finally, we propose a feasible experimental implementation using superconducting circuits, providing a platform to observe the interplay between interactions and disorder in quantum systems.

DOI: 10.1103/4mql-32sg

Source: https://journals.aps.org/pra/abstract/10.1103/4mql-32sg