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arXiv · 1302.7020

Catch-Disperse-Release Readout for Superconducting Qubits

Eyob A. Sete·Andrei Galiautdinov·Eric Mlinar·John M. Martinis·Alexander N. Korotkov
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Abstract

We analyze a single-shot readout for superconducting qubits via the controlled catch, dispersion, and release of a microwave field. A tunable coupler is used to decouple the microwave resonator from the transmission line during the dispersive qubit-resonator interaction, thus circumventing damping from the Purcell effect. We show that if the qubit frequency tuning is sufficiently adiabatic, a fast high-fidelity qubit readout is possible, even in the strongly nonlinear dispersive regime. Interestingly, the Jaynes-Cummings nonlinearity leads to the quadrature squeezing of the resonator field below the standard quantum limit, resulting in a significant decrease of the measurement error.

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Eyob A. Sete, Andrei Galiautdinov, Eric Mlinar, John M. Martinis, Alexander N. Korotkov. 2013-02-27. Catch-Disperse-Release Readout for Superconducting Qubits. https://doi.org/10.1103/physrevlett.110.210501

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