title: Efficient sorting of orbital angular momentum states of light.
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.
authors.affiliation: Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands. j.berkhout@cosine.nl
authors.forename: Gregorius C G
authors.initials: GC
authors.lastname: Berkhout
authors.forename: Martin P J
authors.initials: MP
authors.lastname: Lavery
authors.forename: Johannes
authors.initials: J
authors.lastname: Courtial
authors.forename: Marco W
authors.initials: MW
authors.lastname: Beijersbergen
authors.forename: Miles J
authors.initials: MJ
authors.lastname: Padgett