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arXiv · 1010.4622

Renormalized dynamics in charge qubit measurements by a single electron transistor

JunYan Luo·HuJun Jiao·Jianzhong Wang·Yu Shen·Xiao-Ling He
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Abstract

We investigate charge qubit measurements using a single electron transistor, with focus on the backaction-induced renormalization of qubit parameters. It is revealed the renormalized dynamics leads to a number of intriguing features in the detector's noise spectra, and therefore needs to be accounted for to properly understand the measurement result. Noticeably, the level renormalization gives rise to a strongly enhanced signal-to-noise ratio, which can even exceed the universal upper bound imposed quantum mechanically on linear-response detectors.

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JunYan Luo, HuJun Jiao, Jianzhong Wang, Yu Shen, Xiao-Ling He. 2010-10-22. Renormalized dynamics in charge qubit measurements by a single electron transistor. https://doi.org/10.1016/j.physleta.2010.10.002

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