{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/16261"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/16261","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Photonic sources and detectors for quantum information protocols: a trilogy in eight parts","abstract":"Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-04-20T20:33:38Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 3 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5)","abstract_html":"Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-04-20T20:33:38Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 3 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5)","abstract_has_math":false,"creators":["Rangarajan, Radhika"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Kwiat, Paul G.","Eckstein, James N.","Abbamonte, Peter M.","Vishveshwara, Smitha"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010-05-20T15:16:53Z","date_published":"2010-05-20T15:16:53Z","updated_at":"2026-07-22T22:25:08Z","subjects":["Optical Quantum Information Processing","Quantum Technologies","Quantum Physics","Quantum Optics","Quantum Information","Quantum Computing"],"languages":["en"],"rights":["Copyright 2010 Radhika Rangarajan"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/16261","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Kwiat, Paul G.","Eckstein, James N.","Abbamonte, Peter M.","Vishveshwara, Smitha"]},{"key":"dc:creator","label":"Author","values":["Rangarajan, Radhika"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2010-05-20T15:16:53Z","2010-5"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Optical Quantum Information Processing","Quantum Technologies","Quantum Physics","Quantum Optics","Quantum Information","Quantum Computing"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2010 Radhika Rangarajan"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/16261"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-04-20T20:33:38Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 3 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5)","Made available in DSpace on 2010-05-20T15:16:53Z (GMT). No. of bitstreams: 4 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) 1_Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5) license.txt: 4068 bytes, checksum: 5ea5979e06754b43f45b198e773d1508 (MD5)","Quantum information processing (QIP) promises to revolutionize existing methods of manipulating data, via truly unique paradigms based on fundamental nonclassical physical phenomenon. However, the eventual success of optical QIP depends critically on the available technologies. Currently, creating multiple-photon states is extremely inefficient because almost no source thus far has been well optimized. Additionally, high-efficiency single-photon detectors can drastically improve multi-photon QIP (typical efficiencies are ~70%). In fact, it has been shown that scalable linear optical quantum computing is possible only if the product of the source and detector efficiencies exceeds ~67%. The research presented here focuses on developing optimized source and detector technologies for enabling scalable QIP. The goal of our source research is to develop an ideal “indistinguishable” source of ultrabright polarization-entangled but spatially- and spectrally-unentangled photon pairs. We engineer such an ideal source by first designing spatio-spectrally unentangled photons using optimized and group-velocity matched spontaneous parametric down conversion (SPDC). Next, we generate polarization-entangled photons using the engineered SPDC. Here we present solutions to the various challenges encountered during the indistinguishable source development. We demonstrate high-fidelity ultrafast pulsed and cw-diode laser-pumped sources of polarization-entangled photons, as well as the first production of polarization-entanglement directly from the highly nonlinear biaxial crystal BiB3O6 (BiBO). We also discuss the first experimental confirmation of the emission-angle dependence of the downconversion polarization (the Migdall effect), and a novel scheme for polarization-dependent focusing. The goal of our single-photon detector research is to develop a very high-efficiency detection system that can also resolve incident photon number, a feature absent from the typical detectors employed for QIP. We discuss the various cryogenic, optical and electronic challenges encountered en route to detector development and present details on detector characterization, ultra-short electronics design and photon-number-resolution studies. The source and detector technologies developed here share a common goal: to enhance the efficiency of existing quantum protocols and pave the way for new ones. Here we discuss some of the possible benefits via a popular quantum protocol – teleportation – as well as a novel quantum communication technique – hyper-fingerprinting. Taken as a whole, this dissertation explores viable technological options for enhancing optical quantum information protocols, offers a perspective on the current status and limitations of existing technologies, and highlights the possibilities enabled by optimized photonic sources and detectors."]},{"key":"dc:title","label":"Title","values":["Photonic sources and detectors for quantum information protocols: a trilogy in eight parts"]}]}],"canonical_facts":{"dc:contributor":["Kwiat, Paul G.","Eckstein, James N.","Abbamonte, Peter M.","Vishveshwara, Smitha"],"dc:creator":["Rangarajan, Radhika"],"dc:date":["2010-05-20T15:16:53Z","2010-5"],"dc:description":["Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-04-20T20:33:38Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 3 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5)","Made available in DSpace on 2010-05-20T15:16:53Z (GMT). No. of bitstreams: 4 Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) 1_Rangarajan_Radhika.docx: 37823704 bytes, checksum: 079f863dc0d3a5524e117b2d02ded061 (MD5) Rangarajan_Radhika.pdf: 7854377 bytes, checksum: 0de5c9ffc769f0b1c9c51e94a8ffdf79 (MD5) license.txt: 4068 bytes, checksum: 5ea5979e06754b43f45b198e773d1508 (MD5)","Quantum information processing (QIP) promises to revolutionize existing methods of manipulating data, via truly unique paradigms based on fundamental nonclassical physical phenomenon. However, the eventual success of optical QIP depends critically on the available technologies. Currently, creating multiple-photon states is extremely inefficient because almost no source thus far has been well optimized. Additionally, high-efficiency single-photon detectors can drastically improve multi-photon QIP (typical efficiencies are ~70%). In fact, it has been shown that scalable linear optical quantum computing is possible only if the product of the source and detector efficiencies exceeds ~67%. The research presented here focuses on developing optimized source and detector technologies for enabling scalable QIP. The goal of our source research is to develop an ideal “indistinguishable” source of ultrabright polarization-entangled but spatially- and spectrally-unentangled photon pairs. We engineer such an ideal source by first designing spatio-spectrally unentangled photons using optimized and group-velocity matched spontaneous parametric down conversion (SPDC). Next, we generate polarization-entangled photons using the engineered SPDC. Here we present solutions to the various challenges encountered during the indistinguishable source development. We demonstrate high-fidelity ultrafast pulsed and cw-diode laser-pumped sources of polarization-entangled photons, as well as the first production of polarization-entanglement directly from the highly nonlinear biaxial crystal BiB3O6 (BiBO). We also discuss the first experimental confirmation of the emission-angle dependence of the downconversion polarization (the Migdall effect), and a novel scheme for polarization-dependent focusing. The goal of our single-photon detector research is to develop a very high-efficiency detection system that can also resolve incident photon number, a feature absent from the typical detectors employed for QIP. We discuss the various cryogenic, optical and electronic challenges encountered en route to detector development and present details on detector characterization, ultra-short electronics design and photon-number-resolution studies. The source and detector technologies developed here share a common goal: to enhance the efficiency of existing quantum protocols and pave the way for new ones. Here we discuss some of the possible benefits via a popular quantum protocol – teleportation – as well as a novel quantum communication technique – hyper-fingerprinting. Taken as a whole, this dissertation explores viable technological options for enhancing optical quantum information protocols, offers a perspective on the current status and limitations of existing technologies, and highlights the possibilities enabled by optimized photonic sources and detectors."],"dc:identifier":["http://hdl.handle.net/2142/16261"],"dc:language":["en"],"dc:rights":["Copyright 2010 Radhika Rangarajan"],"dc:subject":["Optical Quantum Information Processing","Quantum Technologies","Quantum Physics","Quantum Optics","Quantum Information","Quantum Computing"],"dc:title":["Photonic sources and detectors for quantum information protocols: a trilogy in eight parts"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:08Z"}