近日，意大利米兰理工大学的Stefano Longhi及其研究团队取得一项新进展。经过不懈努力，他们揭示了光子量子行走中的非相干非厄米趋肤效应。相关研究成果已于2024年4月25日在国际知名学术期刊《光：科学与应用》上发表。

该研究团队成功将趋肤效应的概念引入到完全非相干状态，并证实了在相当普遍（尽管并非绝对）的情况下，非厄米趋肤效应在退相动力学作用下依然能够持续存在。这一成果是通过深入研究非厄米光子量子行走中的非相干光动力学所得出的。

据悉，非厄米趋肤效应描述了某些耗散系统边界附近大量本征态的凝聚现象。这种现象吸引了物理学多个领域，特别是光子学领域的广泛关注。它不仅深化了人们对非厄米系统的认识，还在拓扑现象的基础研究和应用探索中开辟了新的道路。趋肤效应与非平凡点间隙光谱拓扑紧密相关，并在各种合成物质系统，如光子晶格中，得到了实验验证。值得注意的是，在大多数展现非厄米趋肤效应的物理模型中，通常假设存在全波或分波的相干性。

附：英文原文

Title: Incoherent non-Hermitian skin effect in photonic quantum walks

Author: Longhi, Stefano

Issue&Volume: 2024-04-25

Abstract: The non-Hermitian skin effect describes the concentration of an extensive number of eigenstates near the boundaries of certain dissipative systems. This phenomenon has raised a huge interest in different areas of physics, including photonics, deeply expanding our understanding of non-Hermitian systems and opening up new avenues in both fundamental and applied aspects of topological phenomena. The skin effect has been associated to a nontrivial point-gap spectral topology and has been experimentally demonstrated in a variety of synthetic matter systems, including photonic lattices. In most of physical models exhibiting the non-Hermitian skin effect full or partial wave coherence is generally assumed. Here we push the concept of skin effect into the fully incoherent regime and show that rather generally (but not universally) the non-Hermitian skin effect persists under dephasing dynamics. The results are illustrated by considering incoherent light dynamics in non-Hermitian photonic quantum walks.

DOI: 10.1038/s41377-024-01438-w

Source: https://www.nature.com/articles/s41377-024-01438-w