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Published on: February 4, 2017
Light beams with fractional orbital angular momentum and their vortex structure
Jörg B Götte1, Kevin O'Holleran, Daryl Preece
1Department of Physics and Astronomy, SUPA, University of Glasgow, Glasgow G12 8QQ, UK.
Optics Express
|June 11, 2008
Summary
Researchers created stable light beams with fractional orbital angular momentum (OAM) using synthesized Laguerre-Gaussian modes, avoiding unstable phase plates. These beams are ideal for quantum information applications requiring fractional OAM states.
Area of Science:
- Optics and Photonics
- Quantum Information Science
Background:
- Spiral phase plates with non-integer phase steps produce complex and unstable light vortex structures.
- Propagation instability hinders the application of fractional orbital angular momentum (OAM) light beams.
Purpose of the Study:
- To generate and characterize light beams with fractional OAM in a stable and well-defined manner.
- To explore the potential of these stable fractional OAM beams for quantum information processing.
Main Methods:
- Synthesizing Laguerre-Gaussian modes to create light beams carrying fractional OAM.
- Limiting the number of different Gouy phases within the superposition to control beam characteristics.
Main Results:
- Successfully generated light beams with fractional OAM without using phase plates.
- Produced beams with well-characterized propagation due to controlled Gouy phase superpositions.
- Demonstrated structural stability of the synthesized beams.
Conclusions:
- The synthesized fractional OAM beams exhibit structural stability, making them suitable for quantum information applications.
- This method offers a more robust approach to generating fractional OAM light compared to traditional phase plates.
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