Please use this identifier to cite or link to this item:
http://hdl.handle.net/11375/8974
Title: | Controlling Polymer Microstructure Through the Coherence of Light |
Authors: | Shimmel, Whitney E. |
Advisor: | Saravanamuttu, Kalaichelvi |
Department: | Chemistry |
Keywords: | Chemistry;Chemistry |
Publication Date: | 2009 |
Abstract: | <p>This thesis describes modulation instability of a broad beam of partially spatially incoherent laser light propagating in a photopolymerisable organosiloxane. Refractive index changes due to photoinitiated free-radical polymerisation lead to a nonlinear regime in which even weak perturbations in the optical field become amplified. These trigger the spontaneous division of the beam into multiple self-trapped filaments of light. By tuning the spatial coherence of the beam, it was possible to vary the diameter of the self-trapped filaments. Quantitative analyses showed that the relation between filament diameter and spatial incoherence was consistent with a previously developed theoretical model. Because refractive index changes in the photopolymer are irreversible, modulation instability led to a permanent array of self-induced waveguides. In this way, it was possible to control the dimensions of the spontaneously formed polymer microstructure by tuning the incoherence of the optical field.</p> |
URI: | http://hdl.handle.net/11375/8974 |
Identifier: | opendissertations/4138 5157 2023354 |
Appears in Collections: | Open Access Dissertations and Theses |
Files in This Item:
File | Size | Format | |
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fulltext.pdf | 41.38 MB | Adobe PDF | View/Open |
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