An analysis of the Quality of Charge Qubit Measurement by a Strongly Coupled Single-Electron Transistor
We derive a Lindblad-form master equation and a corresponding quantum trajectory model for continuous measurement of a charge qubit by a single electron transistor (SET) operating in the sequential-tunneling regime when the SET-qubit coupling is 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) and show that 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 generalized definitions of measurement time and decoherence time.
Charge qubit Lindblad equation measurement quality single electron transistor strong coupling
Neil P.Oxtoby H.W.Wiseman He-Bi Sun
Centre for Quantum Dynamics,Centre for Quantum Computer Technology,School of Science, Griffith University,Brisbane 4111, Australia
国际会议
Asian Conference on Quantum Onformation Science 2006(2006亚洲量子信息大会)
北京
英文
97-98
2006-09-01（万方平台首次上网日期，不代表论文的发表时间）