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arXiv · 2310.03854

Resonant Schr\"odinger Cat States in Circuit Quantum Electrodynamics

M. Ayyash·X. Xu·M. Mariantoni
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Abstract

We propose a fast scheme to generate Schr\"odinger cat states in a superconducting resonator using a continuously driven qubit without resorting to the dispersive regime, two-photon drives, or engineered two-photon dissipation. We provide analysis for when the qubit is on and off resonance from the drive. We extend our analysis to account for a third level in a weakly-anharmonic qutrit. We also discuss the case of a strongly-anharmonic qutrit. Throughout the paper, we corroborate our analytical results with numerical simulations in the presence of energy relaxation and dephasing of the qubit and resonator using realistic experimental parameters.

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M. Ayyash, X. Xu, M. Mariantoni. 2023-10-05. Resonant Schr\"odinger Cat States in Circuit Quantum Electrodynamics. https://doi.org/10.1103/physreva.109.023703

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