{"id":{"repo_id":"soton","oai_identifier":"oai:eprints.soton.ac.uk:15488"},"canonical_url":"https://search.dev.ndltd.org/etd/soton/oai:eprints.soton.ac.uk:15488","repository":{"repo_id":"soton","name":"University of Southampton","base_url":"https://eprints.soton.ac.uk/cgi/oai2"},"display":{"title":"Novel active waveguide devices in direct-bonded structures","abstract":"This thesis describes a series of experimental studies on the use of direct bonding for optical waveguide fabrication. The direct bonding technique involves contacting two ultra-clean polished surfaces to form an adhesive-free vacuum-tight bond. Optical materials bonded in this way can be formed into waveguide devices, and this work extends direct bonding to include periodically poled materials and a new solid-state ion-exchange process.
The first result of this work describes the fabrication of a 5.5-mm-long, 12-µm-thick periodically poled LiNbO3 planar waveguide buried in LiTaO3. Frequency doubling experiments performed with this device demonstrate a conversion efficiency of 4.3 %W-1, a value 40% greater than that calculated for an optimised bulk device of similar length.
Also demonstrated is a photorefractive iron-doped LiNbO3 waveguide buried in non-photorefractive magnesium-doped LiNbO3. In optical limiting experiments this device demonstrates a change in optical density of 2 and photorefractive response time of 5 milliseconds, representing 20 times greater optical limiting and 60 times faster operational speed than the bulk material.
K+-Na+ ion-exchange between direct-bonded glass layers is studied and used as a novel solid-state technique for waveguide fabrication. This process is also developed to incorporate direct-UV-written channel waveguides in an ion-exchanged buried photosensitive glass layer. Finally, operation of a single-mode channel waveguide laser in neodymium-doped photosensitive SGBN glass (based on a composition of silica, germania, boron, and sodium) is demonstrated, with propagation losses of < 0.3 dB cm-1 and milliwatt-order lasing thresholds.
","abstract_html":"This thesis describes a series of experimental studies on the use of direct bonding for optical waveguide fabrication. The direct bonding technique involves contacting two ultra-clean polished surfaces to form an adhesive-free vacuum-tight bond. Optical materials bonded in this way can be formed into waveguide devices, and this work extends direct bonding to include periodically poled materials and a new solid-state ion-exchange process. <br/>The first result of this work describes the fabrication of a 5.5-mm-long, 12-µm-thick periodically poled LiNbO<sub>3</sub> planar waveguide buried in LiTaO<sub>3</sub>. Frequency doubling experiments performed with this device demonstrate a conversion efficiency of 4.3 %W<sup>-1</sup>, a value 40% greater than that calculated for an optimised bulk device of similar length.<br/>Also demonstrated is a photorefractive iron-doped LiNbO<sub>3</sub> waveguide buried in non-photorefractive magnesium-doped LiNbO<sub>3</sub>. In optical limiting experiments this device demonstrates a change in optical density of 2 and photorefractive response time of 5 milliseconds, representing 20 times greater optical limiting and 60 times faster operational speed than the bulk material. <br/>K<sup>+</sup>-Na<sup>+</sup> ion-exchange between direct-bonded glass layers is studied and used as a novel solid-state technique for waveguide fabrication. This process is also developed to incorporate direct-UV-written channel waveguides in an ion-exchanged buried photosensitive glass layer. Finally, operation of a single-mode channel waveguide laser in neodymium-doped photosensitive SGBN glass (based on a composition of silica, germania, boron, and sodium) is demonstrated, with propagation losses of < 0.3 dB cm<sup>-1</sup> and milliwatt-order lasing thresholds. <br/>","abstract_has_math":false,"creators":["Gawith, C.B.E."],"institution":"University of Southampton","degree_name":"Ph.D.","degree_level":"doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Smith, Peter"],"committee_chairs":[],"committee_members":[],"year":2002,"date_issued":"2002","date_published":"2002","updated_at":"2026-07-24T04:35:42Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Smith, Peter"]},{"key":"dc:creator","label":"Author","values":["Gawith, C.B.E."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2002"]},{"key":"dc:date.issued","label":"Date","values":["2002"]},{"key":"dc:publisher.commercial","label":"Dc Publisher Commercial","values":["University of Southampton"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Optoelectronics Research Centre (pre 2011 reorg)","Department of Physics and Astronomy"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Southampton"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://eprints.soton.ac.uk/15488/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Ph.D."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://eprints.soton.ac.uk/15488/1/Gawith_2002_thesis_2447.pdf","https://eprints.soton.ac.uk/15488/2/gawith_permission.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This thesis describes a series of experimental studies on the use of direct bonding for optical waveguide fabrication. The direct bonding technique involves contacting two ultra-clean polished surfaces to form an adhesive-free vacuum-tight bond. Optical materials bonded in this way can be formed into waveguide devices, and this work extends direct bonding to include periodically poled materials and a new solid-state ion-exchange process.
The first result of this work describes the fabrication of a 5.5-mm-long, 12-µm-thick periodically poled LiNbO3 planar waveguide buried in LiTaO3. Frequency doubling experiments performed with this device demonstrate a conversion efficiency of 4.3 %W-1, a value 40% greater than that calculated for an optimised bulk device of similar length.
Also demonstrated is a photorefractive iron-doped LiNbO3 waveguide buried in non-photorefractive magnesium-doped LiNbO3. In optical limiting experiments this device demonstrates a change in optical density of 2 and photorefractive response time of 5 milliseconds, representing 20 times greater optical limiting and 60 times faster operational speed than the bulk material.
K+-Na+ ion-exchange between direct-bonded glass layers is studied and used as a novel solid-state technique for waveguide fabrication. This process is also developed to incorporate direct-UV-written channel waveguides in an ion-exchanged buried photosensitive glass layer. Finally, operation of a single-mode channel waveguide laser in neodymium-doped photosensitive SGBN glass (based on a composition of silica, germania, boron, and sodium) is demonstrated, with propagation losses of < 0.3 dB cm-1 and milliwatt-order lasing thresholds.
"]},{"key":"dc:format","label":"Dc Format","values":["text"]},{"key":"dc:title","label":"Title","values":["Novel active waveguide devices in direct-bonded structures"]}]}],"canonical_facts":{"dc:contributor.advisor":["Smith, Peter"],"dc:creator":["Gawith, C.B.E."],"dc:date":["2002"],"dc:date.issued":["2002"],"dc:description.abstract":["This thesis describes a series of experimental studies on the use of direct bonding for optical waveguide fabrication. The direct bonding technique involves contacting two ultra-clean polished surfaces to form an adhesive-free vacuum-tight bond. Optical materials bonded in this way can be formed into waveguide devices, and this work extends direct bonding to include periodically poled materials and a new solid-state ion-exchange process.
The first result of this work describes the fabrication of a 5.5-mm-long, 12-µm-thick periodically poled LiNbO3 planar waveguide buried in LiTaO3. Frequency doubling experiments performed with this device demonstrate a conversion efficiency of 4.3 %W-1, a value 40% greater than that calculated for an optimised bulk device of similar length.
Also demonstrated is a photorefractive iron-doped LiNbO3 waveguide buried in non-photorefractive magnesium-doped LiNbO3. In optical limiting experiments this device demonstrates a change in optical density of 2 and photorefractive response time of 5 milliseconds, representing 20 times greater optical limiting and 60 times faster operational speed than the bulk material.
K+-Na+ ion-exchange between direct-bonded glass layers is studied and used as a novel solid-state technique for waveguide fabrication. This process is also developed to incorporate direct-UV-written channel waveguides in an ion-exchanged buried photosensitive glass layer. Finally, operation of a single-mode channel waveguide laser in neodymium-doped photosensitive SGBN glass (based on a composition of silica, germania, boron, and sodium) is demonstrated, with propagation losses of < 0.3 dB cm-1 and milliwatt-order lasing thresholds.
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