Above 99.9% Fidelity Single-Qubit Gates, Two-Qubit Gates, and Readout in a Single Superconducting Quantum Device

Curator's Take

This article shows that a single superconducting chip can now deliver >99.9 % fidelity for both single‑qubit rotations, controlled‑Z two‑qubit gates and simultaneous readout, a milestone that closes the performance gap between isolated gate demonstrations and fully integrated processors. By fine‑tuning qubit‑coupler interactions and introducing a new calibration routine, the authors push error rates into the regime required for surface‑code error correction without sacrificing parallel operation—a key step toward scalable architectures. The result validates that high‑fidelity control can be maintained in realistic multi‑qubit layouts, though further work will be needed to preserve these numbers as device counts grow and crosstalk becomes more complex.

— Mark Eatherly