Implementation of cross resonance gate for a capacitively coupled two fluxonium device in 3D cavity*

Fluxonium qubits stand out with their high anharmonicity and longer coherence times [1,2]. For this reason they are promising candidates for cross resonance gate applications where the weak transmon anharmonicity is one of the main limitations [3]. Our work focuses on the implementation of the cross resonance gate on a capacitively coupled two fluxonium system and suggests an 'all microwave' scheme in a simple 3D resonator geometry. We will present our improved toolbox for the realization of the CR gate in our system and report recent benchmarking results. In particular we will discuss observations of the effect of strong drives on fluxonium qubits in a 3D cavity.

[1] L. B. Nguyen, et. al., Phys. Rev. X 9, 041041 (2019)

[2] A. Somoroff, et. al., arXiv: 2103.08578 (2021)

[3] S. Sheldon, et al., Phys. Rev. A 93, 060302 (2016)