NONLINEAR GUIDED WAVES AND NONLINEAR PRISM COUPLING IN THIN FILM WAVEGUIDES WITH LIQUID-CRYSTAL CLADDING.

Persistent Link:
http://hdl.handle.net/10150/183891
Title:
NONLINEAR GUIDED WAVES AND NONLINEAR PRISM COUPLING IN THIN FILM WAVEGUIDES WITH LIQUID-CRYSTAL CLADDING.
Author:
VALERA ROBLES, JESUS DANIEL.
Issue Date:
1986
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The rigorous descriptions of linear and nonlinear guided wave theory are given together with a geometrical description that helps in the understanding of the physical phenomena taking place. The nonlinear waveguide discussed in this dissertation is composed of a linear thin film and substrate with a cladding material whose refractive index varies with the intensity of the light. Experimentally, this was accomplished, by placing an oriented liquid crystal (highly nonlinear but extremely slow) on top of a thin film glass waveguide. When the liquid crystal used was K15, light-induced mode cutoff was observed. The TE(,0) mode became leaky as the guided wave power was increased. This was a consequence of the light-induced increase in refractive index due to thermal effects. This behaviour was studied as a function of temperature. Light by light modulation was also accomplished with this setup. The theory of the linear and nonlinear prism coupler and the first experimental investigations on the nonlinear prism coupler are given. The nonlinear prism coupler used was obtained by depositing a small amount of MBBA liquid crystal in the gap beween the input coupling prism and the thin film. The basic properties of the nonlinear prism coupler were demonstrated experimentally and the results obtained were verified to have their origin in the temperature component of the nonlinear index of refraction. Good qualitative agreement between the theory developed and experiments were obtained. Bistability and switching in a thin film waveguide with a K18 liquid crystal cladding has been demonstrated for the first time. These experiments made use of the interesting phenomena associated with the nematic to isotropic phase transition. Such behaviour was satisfactorily explained by the intense light scattering associated with the critical opalescence that accompanies such a phase transition in a liquid crystal. Both the TE(,0) and the TM(,0) modes were found to exhibit such behaviour.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Nonlinear waves.; Light, Wave theory of.; Wave guides.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Optical Sciences; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Stegeman, George

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleNONLINEAR GUIDED WAVES AND NONLINEAR PRISM COUPLING IN THIN FILM WAVEGUIDES WITH LIQUID-CRYSTAL CLADDING.en_US
dc.creatorVALERA ROBLES, JESUS DANIEL.en_US
dc.contributor.authorVALERA ROBLES, JESUS DANIEL.en_US
dc.date.issued1986en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe rigorous descriptions of linear and nonlinear guided wave theory are given together with a geometrical description that helps in the understanding of the physical phenomena taking place. The nonlinear waveguide discussed in this dissertation is composed of a linear thin film and substrate with a cladding material whose refractive index varies with the intensity of the light. Experimentally, this was accomplished, by placing an oriented liquid crystal (highly nonlinear but extremely slow) on top of a thin film glass waveguide. When the liquid crystal used was K15, light-induced mode cutoff was observed. The TE(,0) mode became leaky as the guided wave power was increased. This was a consequence of the light-induced increase in refractive index due to thermal effects. This behaviour was studied as a function of temperature. Light by light modulation was also accomplished with this setup. The theory of the linear and nonlinear prism coupler and the first experimental investigations on the nonlinear prism coupler are given. The nonlinear prism coupler used was obtained by depositing a small amount of MBBA liquid crystal in the gap beween the input coupling prism and the thin film. The basic properties of the nonlinear prism coupler were demonstrated experimentally and the results obtained were verified to have their origin in the temperature component of the nonlinear index of refraction. Good qualitative agreement between the theory developed and experiments were obtained. Bistability and switching in a thin film waveguide with a K18 liquid crystal cladding has been demonstrated for the first time. These experiments made use of the interesting phenomena associated with the nematic to isotropic phase transition. Such behaviour was satisfactorily explained by the intense light scattering associated with the critical opalescence that accompanies such a phase transition in a liquid crystal. Both the TE(,0) and the TM(,0) modes were found to exhibit such behaviour.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectNonlinear waves.en_US
dc.subjectLight, Wave theory of.en_US
dc.subjectWave guides.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineOptical Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorStegeman, Georgeen_US
dc.contributor.committeememberBurke, Jamesen_US
dc.contributor.committeememberSargent, Murrayen_US
dc.identifier.proquest8623880en_US
dc.identifier.oclc697809015en_US
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