Light emerging from a spiral phase plate with a non-integer phase step has a complicated vortex structure and is unstable on propagation. We generate light carrying fractional orbital angular momentum (OAM) not with a phase step but by a synthesis of Laguerre-Gaussian modes. By limiting the number of different Gouy phases in the superposition we produce a light beam which is well characterised in terms of its propagation. We believe that their structural stability makes these beams ideal for quantum information processes utilising fractional OAM states.
- light beams
- fractional orbital angular momentum
- vortex structure
Gotte, J. B., O'Holleran, K., Preece, D., Flossmann, F., Franke-Arnold, S., Barnett, S. M., & Padgett, M. J. (2008). Light beams with fractional orbital angular momentum and their vortex structure. Optics Express, 16(2), 993-1006. https://doi.org/10.1364/OE.16.000993