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arXiv · 1508.01743

Broadband Filters for Abatement of Spontaneous Emission in Circuit Quantum Electrodynamics

Nicholas T. Bronn·Yanbing Liu·Jared B. Hertzberg·Antonio D. Córcoles·Andrew A. Houck·Jay M. Gambetta·Jerry M. Chow
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Abstract

The ability to perform fast, high-fidelity readout of quantum bits (qubits) is essential to the goal of building a quantum computer. However, coupling a fast measurement channel to a superconducting qubit typically also speeds up its relaxation via spontaneous emission. Here we use impedance engineering to design a filter by which photons may easily leave the resonator at the cavity frequency but not at the qubit frequency. We implement this broadband filter in both an on-chip and off-chip configuration.

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Nicholas T. Bronn, Yanbing Liu, Jared B. Hertzberg, Antonio D. Córcoles, Andrew A. Houck, Jay M. Gambetta, Jerry M. Chow. 2015-08-07. Broadband Filters for Abatement of Spontaneous Emission in Circuit Quantum Electrodynamics. https://doi.org/10.1063/1.4934867

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