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arXiv · 1807.09204

Singular knot bundle in light

Danica Sugic·Mark R. Dennis
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Abstract

As the size of an optical vortex knot, imprinted in a coherent light beam, is decreased, nonparaxial effects alter the structure of the knotted optical singularity. For knot structures approaching the scale of wavelength, longitudinal polarization effects become non-negligible and the electric and magnetic fields differ, leading to intertwined knotted nodal structures in the transverse and longitudinal polarization components which we call a knot bundle of polarization singularities. We analyze their structure using polynomial beam approximations, and numerical diffraction theory. The analysis reveals features of spin-orbit effects and polarization topology in tightly-focused geometry, and we propose an experiment to measure this phenomenon.

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Danica Sugic, Mark R. Dennis. 2018-07-24. Singular knot bundle in light. https://doi.org/10.1364/josaa.35.001987

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