Control of orbital angular momentum of light with optical fibers

Opt Lett. 2012 Jul 1;37(13):2451-3. doi: 10.1364/OL.37.002451.


We present a fiber-based method for generating vortex beams with a tunable value of orbital angular momentum from -1ℏ to +1ℏ per photon. We propose a new (to our knowledge) method to determine the modal content of the fiber and demonstrate high purity of the desired vortex state (97% after 20 m, even after bends and twists). This method has immediate utility for the multitude of applications in science and technology that exploit vortex light states.