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arXiv · 1011.6529

Ideal Quantum non-demolishing measurement of a flux qubit at variable bias

Ying-Dan Wang·Xiaobo Zhu·Christoph Bruder
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Abstract

We propose a scheme to realize a quantum non-demolition (QND) measurement of a superconducting flux qubit by a Josephson bifurcation amplifier. Our scheme can implement a perfect QND measurement for a qubit subject to a variable magnetic bias. Measurement back-action induced qubit relaxation can be suppressed and hence the QND fidelity is expected to be high over a wide range of bias conditions.

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Ying-Dan Wang, Xiaobo Zhu, Christoph Bruder. 2010-11-30. Ideal Quantum non-demolishing measurement of a flux qubit at variable bias. https://doi.org/10.1103/physrevb.83.134504

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