Light beams with fractional orbital angular momentum and their vortex structure.
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.
Department of Physics and Astronomy, SUPA, University of Glasgow, Glasgow G12 8QQ, UK.
Jörg B
JB
Götte
Kevin
K
O'Holleran
Daryl
D
Preece
Florian
F
Flossmann
Sonja
S
Franke-Arnold
Stephen M
SM
Barnett
Miles J
MJ
Padgett
D003198:Computer Simulation; D008027:Light; D008962:Models, Theoretical; D011789:Quantum Theory; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012542:Scattering, Radiation