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arXiv · 2503.13760

Universal structure of propagation-invariant optical pulses

Rafael Russo Almeida·Dillon Ramsey·Ayman F. Abouraddy·John P. Palastro·Jorge Vieira
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Abstract

Space-time structuring of light - where spatial and temporal degrees of freedom are deliberately coupled and controlled - is an emerging area of optics that enables novel configurations of electromagnetic fields. Of particular importance for applications are optical pulses whose peak intensity travels at an arbitrary, tunable velocity while maintaining its spatiotemporal profile. Space-time wave packets and the ideal flying focus are two prominent realizations of these pulses. Here, we show that these realizations share an identical spatiotemporal field structure, and that this structure represents a universal solution for constant-velocity, propagation-invariant pulses.

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Rafael Russo Almeida, Dillon Ramsey, Ayman F. Abouraddy, John P. Palastro, Jorge Vieira. 2025-03-17. Universal structure of propagation-invariant optical pulses. https://arxiv.org/abs/2503.13760

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