Efficient Sorting of Orbital Angular Momentum States of Light

Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Physical Review Letters (Impact Factor: 7.73). 10/2010; 105(15):153601. DOI: 10.1103/PhysRevLett.105.153601
Source: PubMed

ABSTRACT We present a method to efficiently sort orbital angular momentum (OAM) states of light using two static optical elements. The optical elements perform a Cartesian to log-polar coordinate transformation, converting the helically phased light beam corresponding to OAM states into a beam with a transverse phase gradient. A subsequent lens then focuses each input OAM state to a different lateral position. We demonstrate the concept experimentally by using two spatial light modulators to create the desired optical elements, applying it to the separation of eleven OAM states.

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May 23, 2014