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arXiv · 1909.11079

Free-space propagation of spatio-temporal optical vortices (STOVs)

S. W. Hancock·S. Zahedpour·A. Goffin·H. M. Milchberg
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Abstract

Spatio-temporal optical vortices (STOVs) are a new type of optical orbital angular momentum (OAM) with optical phase circulation in space-time. In prior work [N. Jhajj et al., Phys. Rev X 6, 031037 (2016)], we demonstrated that a STOV is a universal structure emerging from the arrest of self-focusing collapse leading to nonlinear self-guiding in material media. Here, we demonstrate linear generation and propagation in free space of STOV-carrying pulses. Our measurements and simulations demonstrate STOV mediation of space-time energy flow within the pulse and conservation of OAM in space-time. Single-shot amplitude and phase images of STOVs are taken using a new diagnostic, transient grating single-shot supercontinuum spectral interferometry (TG-SSSI).

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S. W. Hancock, S. Zahedpour, A. Goffin, H. M. Milchberg. 2020-01-02. Free-space propagation of spatio-temporal optical vortices (STOVs). https://doi.org/10.1364/optica.6.001547

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