Three-dimensional niobium coaxial cavity with 0.1-second lifetime
Abstract
We report on the internal quality factor of a three-dimensional niobium quarter-wave coaxial cavity that has undergone mid-temperature annealing, exhibiting Q int ≳ 3 × 10 9 at the single-photon level below 20 mK, which corresponds to an internal photon lifetime of τ int ∼ 90 ms . Moreover, Q int of the mid-temperature-annealed cavities remains almost unchanged even after several cooldown cycles and air exposure. These results suggest that stable low-loss niobium oxides are formed by mid-temperature annealing on the surface of a three-dimensional niobium cavity. This surface treatment could be applicable to the fabrication of two-dimensional superconducting circuits and help improve the lifetime of Nb -based superconducting qubits.
Fields of Study & Subjects
Atomic and Subatomic Physics Research
Particle accelerators and beam dynamics
Particle Accelerators and Free-Electron Lasers
Publication details
- Journal / source
- Physical Review Applied
- Publisher
- American Physical Society (APS)
- Volume
- 25
- Issue
- 3
- Pages
- 34076
- Publication date
- 4 February 2026
- Language
- EN