Loss Mechanisms and Quasiparticle Dynamics in Superconducting Microwave Resonators Made of Thin-Film Granular Aluminum.
| Autor: | Grünhaupt L; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany., Maleeva N; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany., Skacel ST; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany., Calvo M; Université Grenoble Alpes, CNRS, Grenoble INP, Insitut Néel, F-38000 Grenoble, France., Levy-Bertrand F; Université Grenoble Alpes, CNRS, Grenoble INP, Insitut Néel, F-38000 Grenoble, France., Ustinov AV; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.; Russian Quantum Center, National University of Science and Technology MISIS, 119049 Moscow, Russia., Rotzinger H; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany., Monfardini A; Université Grenoble Alpes, CNRS, Grenoble INP, Insitut Néel, F-38000 Grenoble, France., Catelani G; JARA Institute for Quantum Information (PGI-11), Forschungszentrum Jülich, 52425 Jülich, Germany., Pop IM; Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.; Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein Leopoldshafen, Germany. |
|---|---|
| Jazyk: | angličtina |
| Zdroj: | Physical review letters [Phys Rev Lett] 2018 Sep 14; Vol. 121 (11), pp. 117001. |
| DOI: | 10.1103/PhysRevLett.121.117001 |
| Abstrakt: | Superconducting high kinetic inductance elements constitute a valuable resource for quantum circuit design and millimeter-wave detection. Granular aluminum (grAl) in the superconducting regime is a particularly interesting material since it has already shown a kinetic inductance in the range of nH/□ and its deposition is compatible with conventional Al/AlOx/Al Josephson junction fabrication. We characterize microwave resonators fabricated from grAl with a room temperature resistivity of 4×10^{3} μΩ cm, which is a factor of 3 below the superconductor to insulator transition, showing a kinetic inductance fraction close to unity. The measured internal quality factors are on the order of Q_{i}=10^{5} in the single photon regime, and we demonstrate that nonequilibrium quasiparticles (QPs) constitute the dominant loss mechanism. We extract QP relaxation times in the range of 1 s and we observe QP bursts every ∼20 s. The current level of coherence of grAl resonators makes them attractive for integration in quantum devices, while it also evidences the need to reduce the density of nonequilibrium QPs. |
| Databáze: | MEDLINE |
| Externí odkaz: |
|