Prof Gengbo Wu having Paper Published in Top Journal – Nature

Prof Gengbo WU (Assistant Professor of EE), Dr Yuansong ZENG (Research Fellow, SKLTMW), and Dr Jin CHEN (Postdoc, SKLTMW) have published a paper in the top journal – Nature, on 14 May 2025. The paper titled “Bulk–spatiotemporal vortex correspondence in gyromagnetic zero-index media” is a collaborative work with scholars coming from The Hong Kong University of Science and Technology, Fudan University, Wuhan University, Shenzhen University, and University of Southampton.

This paper can be found at Nature. To give you a glimpse of the research work, here is a brief introduction: Here we experimentally realize gyromagnetic double-zero-index metamaterials possessing both double-zero-index features and non-reciprocal hallmarks. We discover and demonstrate that a spatiotemporal reflection vortex singularity is always anchored to the Dirac point of the metamaterial, with the vortex charge being determined by the topological invariant leap across the phase transition. This establishes a unique bulk–spatiotemporal vortex correspondence that extends the protected boundary effects into the time domain and characterizes topological phase-transition points. Based on this correspondence, we propose and experimentally demonstrate a mechanism to deterministically generate optical spatiotemporal vortex pulses with firmly fixed central frequency and momentum. Our findings uncover connections between zero-refractive-index photonics, topological photonics and singular optics, which might enable the manipulation of space-time topological light fields using the inherent topology of extreme-parameter metamaterials.