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dc.contributor.authorOxtoby, Neilen_US
dc.contributor.authorWiseman, Howarden_US
dc.contributor.authorSun, He-Bien_US
dc.date.accessioned2017-05-03T11:51:20Z
dc.date.available2017-05-03T11:51:20Z
dc.date.issued2006en_US
dc.date.modified2009-10-13T21:49:01Z
dc.identifier.issn10980121en_US
dc.identifier.doi10.1103/PhysRevB.74.045328en_AU
dc.identifier.urihttp://hdl.handle.net/10072/14399
dc.description.abstractWe consider charge-qubit monitoring (continuous-in-time weak measurement) by a single-electron transistor (SET) operating in the sequential-tunneling regime. We show that commonly used master equations for this regime are not of the Lindblad form that is necessary and sufficient for guaranteeing valid physical states. In this paper we derive a Lindblad-form master equation and a corresponding quantum trajectory model for continuous measurement of the charge qubit by a SET. Our approach requires that the SET-qubit coupling be strong compared to the SET tunnelling rates. We present an analysis of the quality of the qubit measurement in this model (sensitivity versus back-action). Typically, the strong coupling when the SET island is occupied causes back-action on the qubit beyond the quantum back-action necessary for its sensitivity, and hence the conditioned qubit state is mixed. However, in one strongly coupled, asymmetric regime, the SET can approach the limit of an ideal detector with an almost pure conditioned state. We also quantify the quality of the SET using more traditional concepts such as the measurement time and decoherence time, which we have generalized so as to treat the strongly responding regime.en_US
dc.description.peerreviewedYesen_US
dc.description.publicationstatusYesen_AU
dc.format.extent292156 bytes
dc.format.mimetypeapplication/pdf
dc.languageEnglishen_US
dc.language.isoen_AU
dc.publisherAmerican Physical Societyen_US
dc.publisher.placeRidge, NYen_US
dc.publisher.urihttp://prb.aps.org/en_AU
dc.relation.ispartofstudentpublicationNen_AU
dc.relation.ispartofpagefrom045328.01en_US
dc.relation.ispartofpageto045328.11en_US
dc.relation.ispartofjournalPhysical Review B: Condensed Matter and Materials Physicsen_US
dc.relation.ispartofvolume74en_US
dc.rights.retentionYen_AU
dc.subject.fieldofresearchcode240201en_US
dc.titleSensitivity and back action in charge qubit measurements by a strongly coupled single-electron transistoren_US
dc.typeJournal articleen_US
dc.type.descriptionC1 - Peer Reviewed (HERDC)en_US
dc.type.codeC - Journal Articlesen_US
gro.rights.copyrightCopyright 2006 American Physical Society. This is the author-manuscript version of this paper. Reproduced in accordance with the copyright policy of the publisher. Please refer to the journal's website for access to the definitive, published version.en_AU
gro.date.issued2006
gro.hasfulltextFull Text


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