Dissertation/Thesis Abstract

Phase structured wavefields with phase singularities and bispectral properties
by Scipioni, Marco, Ph.D., The University of North Carolina at Charlotte, 2010, 80; 3439274
Abstract (Summary)

The work presented in this dissertation can be subdivided into two parts. The first part illustrates the novel use of a 37 actuator segmented deformable mirror for the creation of optical vortex beams ranging in topological charge from 1 to 10. The segmented deformable mirror offers a dynamic, polarization independent alternative for creating vortex beams with arbitrary charge. An optical vortex mode purity comparison between the deformable mirror and multi-step diffractive phase plates with 16 and 32 discrete steps is carried out both analytically and in simulation. Computer simulations show the intensity and phase of the vortices generated with the two methods. The deformable mirror, by being reconfigurable, shows better mode purity for high charge OVs, while the static phase plate mode efficiency declines due to the fixed number phase quantization.

The second part of the dissertation reviews the concept of the bispectrum (3rd order polyspectrum) and the possibility of creating partially spatially coherent beams with nonzero bispectral characteristics. Numerical simulations show that bispectral properties encoded in an input wavefield are invariant upon propagation in free space.

This result opens the possibility of using the bispectrum as a new degree of freedom for encoding information in a wavefield.

Indexing (document details)
Advisor: Tyson, Robert K.
Commitee: Dmochowski, Jacek, Fiddy, Michael A., Gbur, Greg
School: The University of North Carolina at Charlotte
Department: Optical Science and Engineering (PhD)
School Location: United States -- North Carolina
Source: DAI-B 72/03, Dissertation Abstracts International
Subjects: Optics
Keywords: Bispectrum, Deformable mirror, Optical vortices, Phase, Phase singularities, Wavefields
Publication Number: 3439274
ISBN: 978-1-124-44147-4
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