{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/80859"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/80859","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Transmission Line Model for Material Characterization Using Terahertz Time-Domain Spectroscopy","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["Vandrevala, Farah; 0000-0003-1883-1147"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Einarsson, Erik","Electrical Engineering"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-10-29T16:47:37Z","date_published":"2019-10-29T16:47:37Z","updated_at":"2026-07-27T19:05:25Z","subjects":["electrical engineering"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/80859","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Einarsson, Erik","Electrical Engineering"]},{"key":"dc:creator","label":"Author","values":["Vandrevala, Farah; 0000-0003-1883-1147"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-10-29T16:47:37Z","2019","2019-07-23 13:53:06"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["electrical engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/80859"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","Terahertz time-domain spectroscopy (THz-TDS) relies heavily on knowing precisely the thickness or the refractive index of a material. In practice, one of these values is assumed to be known, or their product is numerically optimized to converge on suitable values. Both approaches are prone to error, and may mask some real features or properties of the material being studied. To eliminate these errors, we use THz-TDS in reflection geometry to accurately and independently determine the thickness by illuminating the step-edge of a substrate atop a metal stage. This method relies solely on the relative time delay among two reflected pulses, and therefore forgoes the need for optimization or assumption of substrate parameters.One of the biggest stumbling blocks of moving THz characterization out of research laboratories and into industrial applications is the oversimplification of the data analysis process, which requires prior knowledge of the material being dielectric or conductive. In this dissertation, we present a generalized transmission line model that enables fast determination of the material type for an unknown sample without making any prior assumptions. Moreover, it helps us understand the pseudo-dispersion effect seen in non-dispersive intrinsic substrates when they are terminated with a bulk conductor.Extremely thin materials can have properties that are far superior to their bulk counterparts. Hence, two-dimensional materials are the focus of research efforts in the quest for novel devices. Graphene's ability to support surface plasmon polaritons (SPPs) in the THz frequency range is of particular interest in the design of nanoscale plasmonic antennas. Since a dielectric-conductor interface is required to excite and sustain SPPs, a negative dielectric function becomes a defining property for graphene, but proper graphene characterization is imperative to guide the antenna design, and evaluate its performance. We use THz-TDS to determine the complex dielectric function and related optical properties of graphene based on its extracted complex conductivity.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Transmission Line Model for Material Characterization Using Terahertz Time-Domain Spectroscopy"]}]}],"canonical_facts":{"dc:contributor":["Einarsson, Erik","Electrical Engineering"],"dc:creator":["Vandrevala, Farah; 0000-0003-1883-1147"],"dc:date":["2019-10-29T16:47:37Z","2019","2019-07-23 13:53:06"],"dc:description":["Ph.D.","Terahertz time-domain spectroscopy (THz-TDS) relies heavily on knowing precisely the thickness or the refractive index of a material. In practice, one of these values is assumed to be known, or their product is numerically optimized to converge on suitable values. Both approaches are prone to error, and may mask some real features or properties of the material being studied. To eliminate these errors, we use THz-TDS in reflection geometry to accurately and independently determine the thickness by illuminating the step-edge of a substrate atop a metal stage. This method relies solely on the relative time delay among two reflected pulses, and therefore forgoes the need for optimization or assumption of substrate parameters.One of the biggest stumbling blocks of moving THz characterization out of research laboratories and into industrial applications is the oversimplification of the data analysis process, which requires prior knowledge of the material being dielectric or conductive. In this dissertation, we present a generalized transmission line model that enables fast determination of the material type for an unknown sample without making any prior assumptions. Moreover, it helps us understand the pseudo-dispersion effect seen in non-dispersive intrinsic substrates when they are terminated with a bulk conductor.Extremely thin materials can have properties that are far superior to their bulk counterparts. Hence, two-dimensional materials are the focus of research efforts in the quest for novel devices. Graphene's ability to support surface plasmon polaritons (SPPs) in the THz frequency range is of particular interest in the design of nanoscale plasmonic antennas. Since a dielectric-conductor interface is required to excite and sustain SPPs, a negative dielectric function becomes a defining property for graphene, but proper graphene characterization is imperative to guide the antenna design, and evaluate its performance. We use THz-TDS to determine the complex dielectric function and related optical properties of graphene based on its extracted complex conductivity.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/80859"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["electrical engineering"],"dc:title":["Transmission Line Model for Material Characterization Using Terahertz Time-Domain Spectroscopy"],"dc:type":["Text","Dissertation"]},"updated_at":"2026-07-27T19:05:25Z"}