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Updated: Jun 29, 2026

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Method for probing the orbital angular momentum of optical vortices in electromagnetic waves from astronomical
Gregorius C G Berkhout1, Marco W Beijersbergen
1Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands. j.berkhout@cosine.nl
Abstract:
We present an efficient method for probing the orbital angular momentum of optical vortices of arbitrary sizes. This method, based on a multipoint interferometer, has its most important application in measuring the orbital angular momentum of light from astronomical sources, opening the way to interesting new astrophysics. We demonstrate its viability by measuring the orbital angular momentum of Laguerre-Gaussian laser beams.
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