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arXiv · 0808.3080

Modeling of quasiparticle-induced excitations of a Josephson charge-phase qubit

J. Könemann·H. Zangerle·B. Egeling·R. Harke·B. Mackrodt·R. Dolata·A. B. Zorin
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Abstract

We have analyzed quasiparticle transitions in an Al charge-phase qubit inducing a dynamic change of the qubit states. The time-averaged mixed state is related to the strong coupling of the qubit to an ensemble of non-equilibrium quasiparticles in the leads. Such quasiparticles tunnel stochastically on and off the island and can excite the qubit. Continuous monitoring of the qubit impedance at a frequency of 80 MHz shows the admixture of the excited state. We present a numerical description of these cyclic transitions and compare it with our experimental data.

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J. Könemann, H. Zangerle, B. Egeling, R. Harke, B. Mackrodt, R. Dolata, A. B. Zorin. 2008-08-22. Modeling of quasiparticle-induced excitations of a Josephson charge-phase qubit. https://arxiv.org/abs/0808.3080

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