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Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 14, Iss. 25 — Dec. 11, 2006
  • pp: 11919–11924

Direct measurement of the skew angle of the Poynting vector in a helically phased beam

Jonathan Leach, Stephen Keen, Miles J. Padgett, Christopher Saunter, and Gordon D. Love  »View Author Affiliations

Optics Express, Vol. 14, Issue 25, pp. 11919-11924 (2006)

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We measure the local skew angle of the Poynting vector within a helically-phased, exp(ilφ), beam using a Shack Hartmann wavefront sensor. It is the skew angle of the Poynting vector with respect to the beam axis that gives rise to the orbital angular momentum of a light beam. We confirm that this skew angle is l/kr, corresponding to an orbital angular momentum of per photon. Measurement of orbital angular momentum in this way is an alternative to interferometric techniques giving a non-ambiguous result to both the magnitude and sign of l from a single measurement, without any restriction on the optical bandwidth.

© 2006 Optical Society of America

OCIS Codes
(010.7350) Atmospheric and oceanic optics : Wave-front sensing
(230.6120) Optical devices : Spatial light modulators
(350.5500) Other areas of optics : Propagation

ToC Category:
Atmospheric and ocean optics

Original Manuscript: August 29, 2006
Manuscript Accepted: November 11, 2006
Published: December 11, 2006

Jonathan Leach, Stephen Keen, Miles J. Padgett, Christopher Saunter, and Gordon D. Love, "Direct measurement of the skew angle of the Poynting vector in a helically phased beam," Opt. Express 14, 11919-11924 (2006)

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