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arXiv · 2306.06258

Broadband Bandpass Purcell Filter for Circuit Quantum Electrodynamics

Haoxiong Yan·Xuntao Wu·Andrew Lingenfelter·Yash J. Joshi·Gustav Andersson·Christopher R. Conner·Ming-Han Chou·Joel Grebel·Jacob M. Miller·Rhys G. Povey·Hong Qiao·Aashish A. Clerk·Andrew N. Cleland
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Abstract

In circuit quantum electrodynamics (QED), qubits are typically measured using dispersively-coupled readout resonators. Coupling between each readout resonator and its electrical environment however reduces the qubit lifetime via the Purcell effect. Inserting a Purcell filter counters this effect while maintaining high readout fidelity, but reduces measurement bandwidth and thus limits multiplexing readout capacity. In this letter, we develop and implement a multi-stage bandpass Purcell filter that yields better qubit protection while simultaneously increasing measurement bandwidth and multiplexed capacity. We report on the experimental performance of our transmission-line--based implementation of this approach, a flexible design that can easily be integrated with current scaled-up, long coherence time superconducting quantum processors.

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Haoxiong Yan, Xuntao Wu, Andrew Lingenfelter, Yash J. Joshi, Gustav Andersson, Christopher R. Conner, Ming-Han Chou, Joel Grebel, Jacob M. Miller, Rhys G. Povey, Hong Qiao, Aashish A. Clerk, Andrew N. Cleland. 2023-06-09. Broadband Bandpass Purcell Filter for Circuit Quantum Electrodynamics. https://doi.org/10.1063/5.0161893

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