AIP conference proceedings

Solid-state qubit measurement with single electron transistors

HuJun Jiao, Feng Li, Shi-Kuan Wang, Xin-Qi Li, Hsi‐Sheng Goan, Yueh-Nan Chen

Published Jan 1, 2008• 0 citations

Abstract

In this paper we consider the continuous weak measurement of a solid‐state qubit by single electron transistors (SET). For single‐dot SET, we find that in nonlinear response regime the signal‐to‐noise ratio can violate the universal upper bound imposed quantum mechanically on any linear response detectors. We understand the violation by means of the cross‐correlation of the detector currents. For double‐dot SET, we discuss its robustness against wider range of temperatures, quantum efficiency, and the relevant open issues unresolved.

DOI: 10.1063/1.3037144

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