Evidence of Long-Range Coherence in Superconducting Networks
- Resource Type
- Periodical
- Authors
- Bizzi, R.; Campanari, V.; Cassi, D.; Merlo, V.; Romeo, F.; Salina, G.; Cirillo, M.
- Source
- IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 33(1):1-6 Jan, 2023
- Subject
- Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Fingers
Josephson junctions
Junctions
Granular superconductors
Arrays
Topology
Superconducting transition temperature
Josephson effect
networks of Josephson junctions
superconductive electronics
- Language
- ISSN
- 1051-8223
1558-2515
2378-7074
Systematic experimental investigations are reported of charge transport in double-comb and star-shaped planar arrays obtained by coupling superconducting islands via Josephson tunnel junctions. The fabrication of the structures is based on a standard niobium trilayer technology with superconducting transition temperature close to 9 K. Noticeable enhancements of Josephson supercurrents and energy gap are recorded. Complementarity between experimental data and theoretical predictions is employed as a tool to clarify the role of different graph topologies in conditioning the singular behavior of synthetic graph-shaped networks. The predictions of the theoretical models are based on the Bose-Einstein topological condensation and a de Gennes-Alexander approach for granular superconductors. Evidence is shown of the dependence, for both gap and Josephson critical currents, on node-to-node connections in the networks, namely on array topology.