Hyperbolic photonic topological insulators

Lei Huang; Lu He; Weixuan Zhang; Huizhen Zhang; Dongning Liu; Xue Feng; Fang Liu; Kaiyu Cui; Yidong Huang; Wei Zhang; Xiangdong Zhang

doi:10.1038/s41467-024-46035-y

Hyperbolic photonic topological insulators

Nat Commun. 2024 Feb 22;15(1):1647. doi: 10.1038/s41467-024-46035-y.

Authors

Lei Huang^#^{1

2}, Lu He^#^{1

2}, Weixuan Zhang^#^{3

4}, Huizhen Zhang^{1

2}, Dongning Liu⁵, Xue Feng⁵, Fang Liu⁵, Kaiyu Cui⁵, Yidong Huang^{5

6}, Wei Zhang^{7

8}, Xiangdong Zhang^{9

10}

Affiliations

¹ Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education, Beijing Institute of Technology, 100081, Beijing, China.
² Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, 100081, Beijing, China.
³ Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education, Beijing Institute of Technology, 100081, Beijing, China. zhangwx@bit.edu.cn.
⁴ Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, 100081, Beijing, China. zhangwx@bit.edu.cn.
⁵ Frontier Science Center for Quantum Information, Beijing National Research Center for Information Science and Technology (BNRist), Electronic Engineering Department, Tsinghua University, Beijing, 100084, China.
⁶ Beijing Academy of Quantum Information Sciences, Beijing, 100193, China.
⁷ Frontier Science Center for Quantum Information, Beijing National Research Center for Information Science and Technology (BNRist), Electronic Engineering Department, Tsinghua University, Beijing, 100084, China. zwei@tsinghua.edu.cn.
⁸ Beijing Academy of Quantum Information Sciences, Beijing, 100193, China. zwei@tsinghua.edu.cn.
⁹ Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education, Beijing Institute of Technology, 100081, Beijing, China. zhangxd@bit.edu.cn.
¹⁰ Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, 100081, Beijing, China. zhangxd@bit.edu.cn.

^# Contributed equally.

Abstract

Topological photonics provides a new degree of freedom to robustly control electromagnetic fields. To date, most of established topological states in photonics have been employed in Euclidean space. Motivated by unique properties of hyperbolic lattices, which are regular tessellations in non-Euclidean space with a constant negative curvature, the boundary-dominated hyperbolic topological states have been proposed. However, limited by highly crowded boundary resonators and complicated site couplings, the hyperbolic topological insulator has only been experimentally constructed in electric circuits. How to achieve hyperbolic photonic topological insulators is still an open question. Here, we report the experimental realization of hyperbolic photonic topological insulators using coupled ring resonators on silicon chips. Boundary-dominated one-way edge states with pseudospin-dependent propagation directions have been observed. Furthermore, the robustness of edge states in hyperbolic photonic topological insulators is also verified. Our findings have potential applications in the field of designing high-efficient topological photonic devices with enhanced boundary responses.