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arXiv · 2012.10806

Second harmonic generation of spatiotemporal optical vortices and conservation of orbital angular momentum

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

Spatiotemporal optical vortices (STOVs) are a new type of intrinsic optical orbital angular momentum (OAM) structure in which the OAM vector is orthogonal to the propagation direction [Optica 6, 1547, (2019)] and the optical phase circulates in space-time. Here, we experimentally and theoretically demonstrate, for the first time, the generation of the second harmonic of a STOV-carrying pulse along with the conservation of STOV-based OAM. Our experiments verify that individual photons can have intrinsic orbital angular momentum perpendicular to their propagation direction.

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S. W. Hancock, S. Zahedpour, H. M. Milchberg. 2020-12-19. Second harmonic generation of spatiotemporal optical vortices and conservation of orbital angular momentum. https://arxiv.org/abs/2012.10806

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