湖北师范大学Jibing Liu课题组近日取得一项新成果。经过不懈努力，他们探明了离散时间量子行走中的最大硬币-位置纠缠与非厄米趋肤效应。这一研究成果于2025年12月2日发表在国际顶尖学术期刊《物理评论A》上。

在本文中，课题组研究人员提出了一个灵活的20步离散时间量子行走的实现，主题是优化的时间复用环路配置。通过优化硬币参数，该课题组研究人员在20步量子行走后实现了最大的硬币位置纠缠。

此外，该课题组研究人员还实验测量了在特定的硬币和损失参数下，硬币位置纠缠的极化平均增长率和演化。小组观察了非对称李雅普诺夫指数分布和非厄米集肤效应引起的纠缠抑制。有趣的是，这种纠缠抑制随着硬币参数的增加而减弱，随着损失参数和进化步骤的增加而增强。他们的研究结果证明了量子行走作为研究非厄米系统中混合纠缠特性和趋肤效应的强大平台的潜力。

据悉，非厄米系统的一个显著特征是趋肤效应，最近引起了广泛的关注。量子行走为研究非厄米效应的潜在机制提供了一个强大的平台。此外，量子行走中的混合纠缠产生被认为是另一个重要的性质。然而，实验研究趋肤效应对非厄米系统纠缠动力学演化的影响仍然是一个挑战。

附：英文原文

Title: Maximal coin-position entanglement and non-Hermitian skin effect in discrete-time quantum walks

Author: Ding Cheng, Yi Li, Hao Zhao, Haijun Kang, Cui Kong, Jiguo Wang, Feng Mei, Chuanjia Shan, Jibing Liu

Issue&Volume: 2025/12/02

Abstract: A distinctive feature of non-Hermitian systems is the skin effect, which has recently attracted widespread attention. Quantum walks provide a powerful platform for investigating the underlying mechanisms of the non-Hermitian skin effect. Additionally, hybrid entanglement generation in quantum walks is recognized as another crucial property. However, experimentally investigating the influence of skin effect on the evolution of entanglement dynamics in the non-Hermitian systems remains a challenge. In this paper, we present a flexible implementation of 20-step discrete-time quantum walks using an optimized time-multiplexed loop configuration. By optimizing the coin parameter, we achieve maximal coin-position entanglement after 20-step quantum walks. Moreover, we experimentally measure the polarization-averaged growth rates and the evolution of coin-position entanglement under specific coin and loss parameters. We observe the asymmetric Lyapunov exponent profiles and the entanglement suppression induced by the non-Hermitian skin effect. Interestingly, this entanglement suppression weakens with increasing coin parameters and enhances with increasing loss parameters and evolution steps. Our results demonstrate the potential of quantum walks as a powerful platform for investigating hybrid entanglement properties and skin effects in non-Hermitian systems.

DOI: 10.1103/7m2n-9vmf

Source: https://journals.aps.org/pra/abstract/10.1103/7m2n-9vmf