{"id":{"repo_id":"chalmers","oai_identifier":"oai:odr.chalmers.se:20.500.12380/159758"},"canonical_url":"https://search.dev.ndltd.org/etd/chalmers/oai:odr.chalmers.se:20.500.12380/159758","repository":{"repo_id":"chalmers","name":"Chalmers University of Technology","base_url":"https://odr.chalmers.se/oai/request"},"display":{"title":"Quantum non-demolition detection of propagating microwave photons","abstract":"Typical photon counters involve absorption of photons to generate electric signals, thus basically destroying the information carried by the photon. This is all the more disastrous if the photon is used as a quantum information carrier, such as a part of an entangled pair. Quantum non-demolition (QND) measurements are de- signed to overcome this limitation. Such a non-destructive photon detection would play a key role in quantum networks where photons can be used as “flying” qubits. In this thesis, using circuit QED we investigate if QND detection of a prop- agating microwave photon is possible. The system considered consists of a three level artificial atom (transmon) interacting with signal and probe fields. The fields are in the microwave regime with their frequencies on par with the energy levels of the transmon. The interaction of these two fields with the artificial atom, imparts a phase change on the probe field via the cross-Kerr effect. By measuring this phase change, we indirectly infer the presence of the signal. In this thesis, we investigate if it is possible to achieve a single photon detection, at first using a single transmon and then using multiple transmons. We find that, while single photon detection is not possible with a single transmon, it is indeed possible with multiple transmons under certain conditions. We also find that with multiple transmons, we can have a large phase change in the probe, which might be desirable in other applications.","abstract_html":"Typical photon counters involve absorption of photons to generate electric signals, thus basically destroying the information carried by the photon. This is all the more disastrous if the photon is used as a quantum information carrier, such as a part of an entangled pair. Quantum non-demolition (QND) measurements are de- signed to overcome this limitation. Such a non-destructive photon detection would play a key role in quantum networks where photons can be used as “flying” qubits. In this thesis, using circuit QED we investigate if QND detection of a prop- agating microwave photon is possible. The system considered consists of a three level artificial atom (transmon) interacting with signal and probe fields. The fields are in the microwave regime with their frequencies on par with the energy levels of the transmon. The interaction of these two fields with the artificial atom, imparts a phase change on the probe field via the cross-Kerr effect. By measuring this phase change, we indirectly infer the presence of the signal. In this thesis, we investigate if it is possible to achieve a single photon detection, at first using a single transmon and then using multiple transmons. We find that, while single photon detection is not possible with a single transmon, it is indeed possible with multiple transmons under certain conditions. We also find that with multiple transmons, we can have a large phase change in the probe, which might be desirable in other applications.","abstract_has_math":false,"creators":["Sathyamoorthy, Sankar Raman"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Chalmers tekniska högskola / Institutionen för mikroteknologi och nanovetenskap","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012","date_published":"2012","updated_at":"2026-08-21T16:43:26Z","subjects":["Grundläggande vetenskaper","Informations- och kommunikationsteknik","Nanovetenskap och nanoteknik","Atomfysik","Mesoskopisk fysik","Basic Sciences","Information & Communication Technology","Nanoscience & Nanotechnology","Atomic physics","Mesoscopic physics"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.12380/159758","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"source_record":{"url":"https://odr.chalmers.se/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Aodr.chalmers.se%3A20.500.12380%2F159758","prefix":"dim"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Chalmers tekniska högskola / Institutionen för mikroteknologi och nanovetenskap","Chalmers University of Technology / Department of Microtechnology and Nanoscience"]},{"key":"dc:creator","label":"Author","values":["Sathyamoorthy, Sankar Raman"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2019-07-03T12:51:02Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2019-07-03T12:51:02Z"]},{"key":"dc:date.issued","label":"Date","values":["2012"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Grundläggande vetenskaper","Informations- och kommunikationsteknik","Nanovetenskap och nanoteknik","Atomfysik","Mesoskopisk fysik","Basic Sciences","Information & Communication Technology","Nanoscience & Nanotechnology","Atomic physics","Mesoscopic physics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/20.500.12380/159758"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Typical photon counters involve absorption of photons to generate electric signals, thus basically destroying the information carried by the photon. This is all the more disastrous if the photon is used as a quantum information carrier, such as a part of an entangled pair. Quantum non-demolition (QND) measurements are de- signed to overcome this limitation. Such a non-destructive photon detection would play a key role in quantum networks where photons can be used as “flying” qubits. In this thesis, using circuit QED we investigate if QND detection of a prop- agating microwave photon is possible. The system considered consists of a three level artificial atom (transmon) interacting with signal and probe fields. The fields are in the microwave regime with their frequencies on par with the energy levels of the transmon. The interaction of these two fields with the artificial atom, imparts a phase change on the probe field via the cross-Kerr effect. By measuring this phase change, we indirectly infer the presence of the signal. In this thesis, we investigate if it is possible to achieve a single photon detection, at first using a single transmon and then using multiple transmons. We find that, while single photon detection is not possible with a single transmon, it is indeed possible with multiple transmons under certain conditions. We also find that with multiple transmons, we can have a large phase change in the probe, which might be desirable in other applications."]},{"key":"dc:title","label":"Title","values":["Quantum non-demolition detection of propagating microwave photons"]}]}],"canonical_facts":{"dc:contributor.department":["Chalmers tekniska högskola / Institutionen för mikroteknologi och nanovetenskap","Chalmers University of Technology / Department of Microtechnology and Nanoscience"],"dc:creator":["Sathyamoorthy, Sankar Raman"],"dc:date.accessioned":["2019-07-03T12:51:02Z"],"dc:date.available":["2019-07-03T12:51:02Z"],"dc:date.issued":["2012"],"dc:description.abstract":["Typical photon counters involve absorption of photons to generate electric signals, thus basically destroying the information carried by the photon. This is all the more disastrous if the photon is used as a quantum information carrier, such as a part of an entangled pair. Quantum non-demolition (QND) measurements are de- signed to overcome this limitation. Such a non-destructive photon detection would play a key role in quantum networks where photons can be used as “flying” qubits. In this thesis, using circuit QED we investigate if QND detection of a prop- agating microwave photon is possible. The system considered consists of a three level artificial atom (transmon) interacting with signal and probe fields. The fields are in the microwave regime with their frequencies on par with the energy levels of the transmon. The interaction of these two fields with the artificial atom, imparts a phase change on the probe field via the cross-Kerr effect. By measuring this phase change, we indirectly infer the presence of the signal. In this thesis, we investigate if it is possible to achieve a single photon detection, at first using a single transmon and then using multiple transmons. We find that, while single photon detection is not possible with a single transmon, it is indeed possible with multiple transmons under certain conditions. We also find that with multiple transmons, we can have a large phase change in the probe, which might be desirable in other applications."],"dc:identifier.uri":["https://hdl.handle.net/20.500.12380/159758"],"dc:language.iso":["eng"],"dc:subject":["Grundläggande vetenskaper","Informations- och kommunikationsteknik","Nanovetenskap och nanoteknik","Atomfysik","Mesoskopisk fysik","Basic Sciences","Information & Communication Technology","Nanoscience & Nanotechnology","Atomic physics","Mesoscopic physics"],"dc:title":["Quantum non-demolition detection of propagating microwave photons"]},"updated_at":"2026-08-21T16:43:26Z"}