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arXiv · 2608.00618

Generation and manipulation of multipole and vortex events in (1+1)-dimensional spacetime

Yiming Pan·Guowei Chen
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Abstract

An event is usually regarded as a zero-dimensional coordinate label in spacetime, rather than as an object with spatial extent, internal structure or topology. Here we show that in nonlinear photonic spacetime crystals, a complete energy-momentum gap ($\omega k$-gap) suppresses extended radiation channels, while Kerr self-trapping localizes an optical occurrence in the physical $(x,t)$ plane. Imposing and relaxing symmetry constraints then yields multipole and vortex events with distinct internal structure. Their spacetime action of these states establishes a hierarchy of structural cost, Bogoliubov-de Gennes spectra distinguish phase-winding vortices from real-valued multipoles, and initial-value reconstructions provide an independent robustness check together with a finite preparation window. Using representative optical parameters, we predict that these structured events span transverse scales of 30-60 $\mu$m and temporal duration of 85-170 fs. These results suggest that an event can be treated not only as a point label, but also as a localized wave object with controllable internal degrees of freedom, offering a route to wave control in time-varying nonlinear media.

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Yiming Pan, Guowei Chen. 2026-08-01. Generation and manipulation of multipole and vortex events in (1+1)-dimensional spacetime. https://arxiv.org/abs/2608.00618

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