Year: 2026
Type: article
Abstract: Time-varying orbital angular momentum (OAM) beams are fascinating due to their rich physics and essentially unbounded degrees of freedom. Yet, despite this promise, their practical use in high-capacity communication has not been demonstrated. We introduce a spatiotemporal topological comb (ST-Comb) as a programmable information carrier in which digital data are encoded into a generalized spatiotemporal-topological state space, rather than into a single vortex beam or an OAM mode. The accessible states are defined by temporal slots, spatiotemporal phase winding, radial topology, coherent topological superpositions, and ST-CEP-dependent spectral fingerprints. A Hyper-DoF ST-Comb modulator programs these variables in the $$k_x$$ k x - $$\omega$$ ω plane, while a self-referenced Guide-Star pulse enables coherent reconstruction relative to an intrinsic optical reference. In the present proof-of-concept, we demonstrate 154 mapped digital bits per wavepacket, recovered with $$100\%$$ 100 % recognition accuracy under tested laboratory, phase-screen-equivalent turbulence, and 100 m outdoor field-trial conditions. The results chart a path toward reconfigurable ultrafast photonics, where programmable spatiotemporal-topological states provide a robust physical alphabet for high-dimensional optical interconnects.
Source: eLight
Institutions: University of Shanghai for Science and Technology, Yunnan University, Westlake University, King's College London, TU Wien, Shanghai Jiao Tong University, Karlsruhe Institute of Technology, Fudan University, State Key Laboratory of Surface Physics, Hiroshima University, International Institute for Sustainability with Knotted Chiral Meta Matter, Yunnan Normal University
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4416767161