Nankai University News Network (Correspondent Cheng Dan). The phenomenon of vortices is pervasive in nature, manifesting across a broad range of scales, from the motion of particles at the quantum level to the distribution of stars in galaxies. In the field of optics, Allen and colleagues first demonstrated in 1992 that vortex beams carry orbital angular momentum (OAM), thereby ushering in a new era in vortex beam research, bridging classical and quantum perspectives. This seminal discovery not only expanded the foundational theory of optics but also opened up promising applications in various domains, including modern optical communication, quantum networks, and micro-nano manipulation. However, despite these advancements, the practical deployment of vortex beams still faces significant challenges, such as limited stable propagation distances and low fidelity. Overcoming these obstacles will require the development of novel structural designs and innovative technical principles.

Recently, a research team led by Professors Zhigang Chen and Jingjun Xu from the School of Physics and the TEDA Institute of Applied Physics at Nankai University, in collaboration with research groups from the University of Zagreb in Croatia and INRS University in Canada, successfully designed and constructed the first-ever single-channel topological disclination optical experimental platform with chiral symmetry. This platform enables the realization of topological double protection and robust vortex transport. Additionally, the team proposed a method for filtering vortex modes of specific orders by manipulating the topological properties of the structure. This innovative work advances the understanding of the interplay between higher-order topology, orbital angular momentum, and the complex structures of disclination, offering new insights into light field control and the development of novel optical vortex devices. The related research was published in Nature Photonics under the title Topological Orbital Angular Momentum Extraction and Twofold Protection of Vortex Transport.

This work is completed with Nankai University as the first affiliation, postdoctoral fellows Dr. Zhichan Hu, Dr. D. Bongiovanni, and doctoral student Ziteng Wang as the co-first authors. Professors Zhigang Chen, Jingjun Xu, along with Distinguished Visiting Professor H. Buljan, serve as the co-corresponding authors. Collaborators also include doctoral student Xiangdong Wang, Professor Daohong Song from Nankai University, and Professor R. Morandotti from INRS in Canada. This work is supported by the Key Research and Development Program of the Ministry of Science and Technology, the National Natural Science Foundation of China (NSFC) Key Project, and the China Postdoctoral Innovative Talent Support Program, etc.

Nature Photonics is widely regarded as one of the foremost journals in the field of optics. Chen's research group has previously made several seminal contributions to the advancing field of topological photonics, with their work published in leading academic journals, including Science, Nature Physics, Nature Communications, and eLight.

Link of the paper: https://rdcu.be/d0Rt6

（Edited and translated by Nankai News Team.)