Recovery Dynamics of a Gap-Engineered Transmon after a Quasiparticle Burst
Abstract
Ionizing radiation impacts create bursts of quasiparticle density in superconducting qubits. These bursts temporarily degrade qubit coherence, which can be detrimental for quantum error correction. Here, we experimentally resolve quasiparticle bursts in 3D gap-engineered transmon qubits by continuously monitoring qubit transitions. Gap engineering allows us to reduce the burst detection rate by a factor of 5. This reduction falls 4 orders of magnitude short of that expected if the quasiparticles were to quickly thermalize to the cryostat temperature. We associate the limited effect of gap engineering with the slow thermalization of the phonons in our chips after the burst.
Fields of Study & Subjects
Quantum and electron transport phenomena
Quantum Information and Cryptography
Physics of Superconductivity and Magnetism
Publication details
- Journal / source
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Volume
- 136
- Issue
- 5
- Pages
- 050601–050601
- Publication date
- 7 January 2026
- Language
- EN