Multi-qubit correlated quasiparticle transitions in large array of tantalum transmon qubits: Part I*

Quantum error correction is a crucial aspect in realizing a universal quantum computer. Ensuring errors are uncorrelated in both space and time is a significant requirement. However, recent studies have revealed correlated errors, such as charge noise, two-level-system drift, and energy relaxation in superconducting qubits, induced by cosmic rays. This work focuses on observing correlated errors related to quasiparticle transitions in a large array of tantalum transmon qubits. The results demonstrate that multi-qubit correlated quasiparticle transition events are more frequent than multi-qubit correlated energy relaxation events, affirming their association with quasiparticle bursts. Interestingly, the average rate of multi-qubit correlated energy relaxation events in tantalum qubits was found to be smaller than that in aluminum qubits, possibly attributed to the stronger electron-phonon interaction in tantalum. Part I of the presentation emphasizes the experimental design, setup, and calibration.