近日，华中科技大学的祝雪丰及其研究小组与浙江大学的李鹰等人合作并取得一项新进展。经过不懈努力，他们成功观察到热扩散中的非厄米集肤效应。相关研究成果已于2024年3月2日在国际知名学术期刊《科学通报》上发表。

在这项工作中，研究人员设计了一个基于改进的Su-Schrieffer-Heeger模型的热扩散晶格，并演示了扩散的非厄米集肤效应。在该模型中，通过适当的结构参数配置，可以很好地实现各晶胞内温度场的非对称耦合。研究人员发现温度场有向目标边界集中的趋势，这对初始激励条件具有鲁棒性。因此，研究人员通过实验证明了非厄米集肤效应热扩散中的应用，并验证了它对各种缺陷的鲁棒性。

这项研究工作为探索扩散系统中的非厄米物理提供了一个平台，它在高效集热、高灵敏度热传感等方面具有重要的应用。

据悉，厄米体系向非厄米体系的范式转换深刻地改变了拓扑系统的固有性质，导致了各种前所未有的效应，如非厄米集肤效应(non- hermite skin effect, NHSE)。在过去的十年中，NHSE已经在量子、光学和声学系统中得到了证明。除了这些波系统，扩散系统中的NHSE尚未被观察到，尽管最近在拓扑热扩散的研究中取得了大量进展。

附：英文原文

Title: Observation of non-Hermitian skin effect in thermal diffusion

Author: Yun-Kai Liu, Pei-Chao Cao, Minghong Qi, Qiang-Kai-Lai Huang, Feng Gao,Yu-Gui Peng, Ying Li, Xue-Feng Zhu

Issue&Volume: 2024/03/02

Abstract: The paradigm shift of Hermitian systems into the non-Hermitian regime profoundly modifies inherent property of the topological systems, leading to various unprecedented effects such as the non-Hermitian skin effect (NHSE). In the past decade, the NHSE has been demonstrated in quantum, optical and acoustic systems. Beside those wave systems, the NHSE in diffusive systems has not yet been observed, despite recent abundant advances in the study of topological thermal diffusion. In this work, we design a thermal diffusion lattice based on a modified Su-Schrieffer-Heeger model and demonstrate the diffusive NHSE. In the proposed model, the asymmetric temperature field coupling inside each unit cell can be judiciously realized by appropriate configurations of structural parameters. We find that the temperature fields trend to concentrate toward the target boundary which is robust against initial excitation conditions. We thus experimentally demonstrated the NHSE in thermal diffusion and verified its robustness against various defects. Our work provides a platform for exploration of non-Hermitian physics in the diffusive systems, which has important applications in efficient heat collection, highly sensitive thermal sensing and others.

DOI: 10.1016/j.scib.2024.02.040

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324001427