4 papers
Effect of metal encapsulation on bulk superconducting properties of niobium thin films used in qubits
Amlan Datta, Kamal R. Joshi, Sunil Ghimire +18
Niobium metal occupies nearly 100\% of the volume of a typical 2D transmon device. While the aluminum Josephson junction is of utmost importance, maintaining quantum coherence acro…
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…
Correlating Superconducting Qubit Performance Losses to Sidewall Near-Field Scattering via Terahertz Nanophotonics
Richard H. J. Kim, Samuel J. Haeuser, Joong-Mok Park +16
Elucidating dielectric losses, structural heterogeneity, and interface imperfections is critical for improving coherence in superconducting qubits. However, most diagnostics rely o…
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…