6 papers
Oxygen distribution and segregation at grain boundaries in Nb and Ta-encapsulated Nb thin films for superconducting qubits
Jaeyel Lee, Dieter Isheim, Zuhawn Sung +14
We report on atomic-scale analyses of oxygen distribution and segregation at grain boundaries (GBs) of Nb and Ta-encapsulated Nb (Ta/Nb) thin films for superconducting qubits using…
Comparison of Nb and Ta Pentoxide Loss Tangents for Superconducting Quantum Devices
D. P. Goronzy, W. W. Mah, P. G. Lim +14
Superconducting transmon qubits are commonly made with thin-film Nb wiring, but recent studies have shown increased performance with Ta wiring. In this work, we compare the resonat…
Vortex-Controlled Quasiparticle Multiplication and Self-Growth Dynamics in Superconducting Resonators
Joong M. Park, Martin Mootz, Richard H. J. Kim +11
Even in the quantum limit, non-equilibrium quasiparticle (QP) populations induce QP poisoning that irreversibly relaxes the quantum state and significantly degrades the coherence o…
X-ray scattering investigation of hydride surface segregation in epitaxial Nb films
David A. Garcia-Wetten, Philip J. Ryan, Jong Woo Kim +4
Hydride precipitation in niobium-based, superconducting circuits is a damaging side-effect of hydrofluoric acid treatments used to clean and thin the Nb surface oxides and Si oxide…
Identifying Materials-Level Sources of Performance Variation in Superconducting Transmon Qubits
Akshay A. Murthy, Mustafa Bal, Michael J. Bedzyk +46
The Superconducting Materials and Systems (SQMS) Center, a DOE National Quantum Information Science Research Center, has conducted a comprehensive and coordinated study using super…
Loss tangent fluctuations due to two-level systems in superconducting microwave resonators
André Vallières, Megan E. Russell, Xinyuan You +10
Superconducting microwave resonators are critical to quantum computing and sensing technologies. Additionally, they are common proxies for superconducting qubits when determining t…