Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Bulletin of the American Physical Society

Improved coherence times for transmon qubits in two-dimensional resonators

Simon Gustavsson, Archana Kamal, Theodore Gudmundsen, Jonilyn Yoder, Paul B. Welander, Xiaoyue Jin, Fei Yan, David J. Hover, Andrew J. Kerman, Adam Sears, Terry P. Orlando, William D. Oliver

Published Mar 4, 2014• 0 citations
OpenAlex

Related papers

Millisecond lifetimes and coherence times in 2D transmon qubits

Matthew P. Bland, Faranak Bahrami, Jeronimo G. C. Martinez +14 more

Nature•Nov 5, 2025•57 citations

Extended coherence times of superconducting transmon qubits

Erik A. Lucero, Matthias Steffen, Jay Gambetta +2 more

Bulletin of the American Physical Society•Mar 18, 2013•1 citation

Investigating decoherence in the transmon qubit using a 3D resonator

Hanhee Paik, David Schuster, Lev S. Bishop +5 more

Bulletin of the American Physical Society•Mar 25, 2011•0 citations

Real-Time Correlation of Relaxation, Dephasing, and Two-level System Dynamics in Transmon Qubits

Ambrose Yang, Alexander M. Young, Paal H. Prestegaard +13 more

Materials improvements in transmon qubits have yielded remarkable advances in qubit lifetimes (T1)and coherence times (T2). However, state-of-the-art superconducting qubits experience temporal fluctuations in their performance, which limit gate fidelities and quantum processor performance. We observe correlated increases in qubit relaxation and dephasing rates that last for minutes to hours, which we call T1 and T2 excursions. Using interleaved lifetime and coherence time measurements, noise spectroscopy, and two-level-system (TLS) spectroscopy, we find that these excursions are caused by single or few strongly-coupled TLS defects that spectrally diffuse into resonance with the qubit frequency. Our measurement protocol provides a powerful tool for understanding the noise sources that cause temporal fluctuations in superconducting qubit performance.

quant-pharXiv:2610.34485•Oct 27, 2026•0 citations

New material platform for superconducting transmon qubits with coherence times exceeding 0.3 milliseconds

Alexander P. M. Place, Lila V. H. Rodgers, Pranav Mundada +18 more

The superconducting transmon qubit is a leading platform for quantum computing and quantum science. Building large, useful quantum systems based on transmon qubits will require significant improvements in qubit relaxation and coherence times, which are orders of magnitude shorter than limits imposed by bulk properties of the constituent materials. This indicates that relaxation likely originates from uncontrolled surfaces, interfaces, and contaminants. Previous efforts to improve qubit lifetimes have focused primarily on designs that minimize contributions from surfaces. However, significant improvements in the lifetime of two-dimensional transmon qubits have remained elusive for several years. Here, we fabricate two-dimensional transmon qubits that have both lifetimes and coherence times with dynamical decoupling exceeding 0.3 milliseconds by replacing niobium with tantalum in the device. We have observed increased lifetimes for seventeen devices, indicating that these material improvements are robust, paving the way for higher gate fidelities in multi-qubit processors.

arXiv:2003.00024•Nature Communications•Mar 19, 2021•562 citations

Measurements of coherence times on a transmon qubit with superconducting bandgap engineering

Luyan Sun, L. DiCarlo, Luigi Frunzio +4 more

Bulletin of the American Physical Society•Mar 18, 2010•0 citations
Materials improvements in transmon qubits have yielded remarkable advances in qubit lifetimes (T1)and coherence times (T2). However, state-of-the-art superconducting qubits experience temporal fluctuations in their performance, which limit gate fidelities and quantum processor performance. We observe correlated increases in qubit relaxation and dephasing rates that last for minutes to hours, which we call T1 and T2 excursions. Using interleaved lifetime and coherence time measurements, noise spectroscopy, and two-level-system (TLS) spectroscopy, we find that these excursions are caused by single or few strongly-coupled TLS defects that spectrally diffuse into resonance with the qubit frequency. Our measurement protocol provides a powerful tool for understanding the noise sources that cause temporal fluctuations in superconducting qubit performance.
The superconducting transmon qubit is a leading platform for quantum computing and quantum science. Building large, useful quantum systems based on transmon qubits will require significant improvements in qubit relaxation and coherence times, which are orders of magnitude shorter than limits imposed by bulk properties of the constituent materials. This indicates that relaxation likely originates from uncontrolled surfaces, interfaces, and contaminants. Previous efforts to improve qubit lifetimes have focused primarily on designs that minimize contributions from surfaces. However, significant improvements in the lifetime of two-dimensional transmon qubits have remained elusive for several years. Here, we fabricate two-dimensional transmon qubits that have both lifetimes and coherence times with dynamical decoupling exceeding 0.3 milliseconds by replacing niobium with tantalum in the device. We have observed increased lifetimes for seventeen devices, indicating that these material improvements are robust, paving the way for higher gate fidelities in multi-qubit processors.