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arXiv · 2301.00110

Fast high-fidelity charge readout by operating the cavity-embedded Cooper pair transistor in the Kerr bistable regime

Bhargava Thyagarajan·Sisira Kanhirathingal·Benjamin L. Brock·Juliang Li·Miles P. Blencowe·Alexander J. Rimberg
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Abstract

Operating the cavity-embedded Cooper pair transistor (cCPT) in the Kerr bistable regime, we demonstrate single-shot resolution between two charge states that are $0.09e$ apart. The measurement is performed with 94$\%$ fidelity in a duration of 3 $\mu$s. The drive power at which the measurement is performed corresponds to only 20 intracavity photons on average in the high oscillation amplitude state of the cCPT, which is orders-of-magnitude smaller than that in rf-SETs. We find that the limiting factor for this mode of operation of the cCPT is the spontaneous fluctuation-induced switching between the two metastable oscillation amplitude states. We present empirical data on the variation of the switching dynamics with drive parameters and cCPT DC bias.

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Bhargava Thyagarajan, Sisira Kanhirathingal, Benjamin L. Brock, Juliang Li, Miles P. Blencowe, Alexander J. Rimberg. 2022-12-31. Fast high-fidelity charge readout by operating the cavity-embedded Cooper pair transistor in the Kerr bistable regime. https://arxiv.org/abs/2301.00110

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