Zou Deyuan, Chen Tian, He Wenjing, Bao Jiacheng, Lee Ching Hua, Sun Houjun, Zhang Xiangdong
Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education, Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, 100081, Beijing, China.
Beijing Key Laboratory of Millimeter Wave and Terahertz Techniques, School of Information and Electronics, Beijing Institute of Technology, Beijing, 100081, China.
Nat Commun. 2021 Dec 10;12(1):7201. doi: 10.1038/s41467-021-26414-5.
Robust boundary states epitomize how deep physics can give rise to concrete experimental signatures with technological promise. Of late, much attention has focused on two distinct mechanisms for boundary robustness-topological protection, as well as the non-Hermitian skin effect. In this work, we report the experimental realizations of hybrid higher-order skin-topological effect, in which the skin effect selectively acts only on the topological boundary modes, not the bulk modes. Our experiments, which are performed on specially designed non-reciprocal 2D and 3D topolectrical circuit lattices, showcases how non-reciprocal pumping and topological localization dynamically interplays to form various states like 2D skin-topological, 3D skin-topological-topological hybrid states, as well as 2D and 3D higher-order non-Hermitian skin states. Realized through our highly versatile and scalable circuit platform, theses states have no Hermitian nor lower-dimensional analog, and pave the way for applications in topological switching and sensing through the simultaneous non-trivial interplay of skin and topological boundary localizations.
稳健的边界态体现了深奥的物理学如何产生具有技术前景的具体实验特征。近来，很多注意力都集中在两种不同的边界稳健性机制上——拓扑保护以及非厄米趋肤效应。在这项工作中，我们报告了混合高阶趋肤 - 拓扑效应的实验实现，其中趋肤效应仅选择性地作用于拓扑边界模式，而非体态模式。我们在专门设计的非互易二维和三维拓扑电路晶格上进行的实验，展示了非互易泵浦和拓扑局域化如何动态相互作用以形成各种状态，如二维趋肤 - 拓扑、三维趋肤 - 拓扑 - 拓扑混合态以及二维和三维高阶非厄米趋肤态。通过我们高度通用且可扩展的电路平台实现的这些状态，没有厄米类似物也没有低维类似物，并通过趋肤和拓扑边界局域化的同时非平凡相互作用为拓扑开关和传感应用铺平了道路。
