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arXiv · 1704.04421

Approaching ultra-strong coupling in Transmon circuit-QED using a high-impedance resonator

Sal J. Bosman·Mario F. Gely·Vibhor Singh·Daniel Bothner·Andres Castellanos-Gomez·Gary A. Steele
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Abstract

In this experiment, we couple a superconducting Transmon qubit to a high-impedance $645\ \Omega$ microwave resonator. Doing so leads to a large qubit-resonator coupling rate $g$, measured through a large vacuum Rabi splitting of $2g\simeq 910$ MHz. The coupling is a significant fraction of the qubit and resonator oscillation frequencies $\omega$, placing our system close to the ultra-strong coupling regime ($\bar{g}=g/\omega=0.071$ on resonance). Combining this setup with a vacuum-gap Transmon architecture shows the potential of reaching deep into the ultra-strong coupling $\bar{g} \sim 0.45$ with Transmon qubits.

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Sal J. Bosman, Mario F. Gely, Vibhor Singh, Daniel Bothner, Andres Castellanos-Gomez, Gary A. Steele. 2017-04-14. Approaching ultra-strong coupling in Transmon circuit-QED using a high-impedance resonator. https://doi.org/10.1103/physrevb.95.224515

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