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Hybridized solid-state qubit in the charge-flux regime

J. Q. You·J. S. Tsai·Franco Nori
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Abstract

Most superconducting qubits operate in a regime dominated by either the electrical charge or the magnetic flux. Here we study an intermediate case: a hybridized charge-flux qubit with a third Josephson junction (JJ) added into the SQUID loop of the Cooper-pair box. This additional JJ allows the optimal design of a low-decoherence qubit. Both charge and flux $1/f$ noises are considered. Moreover, we show that an efficient quantum measurement of either the current or the charge can be achieved by using different area sizes for the third JJ.

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J. Q. You, J. S. Tsai, Franco Nori. 2005-12-18. Hybridized solid-state qubit in the charge-flux regime. https://doi.org/10.1103/physrevb.73.014510

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