Magnetic Josephson Junctions With Superconducting Interlayer for Cryogenic Memory

We investigate a Magnetic Josephson Junction (MJJ) - a superconducting device with ferromagnetic barrier for a scalable high-density cryogenic memory compatible with energy-efficient single flux quantum (SFQ) circuits. The superconductor-insulator-superconductor-ferromagnet-superconductor (SIS '...

Full description

Saved in:
Bibliographic Details
Published inIEEE transactions on applied superconductivity Vol. 23; no. 3; p. 1701208
Main Authors Vernik, I. V., Bol'ginov, V. V., Bakurskiy, S. V., Golubov, A. A., Kupriyanov, M. Y., Ryazanov, V. V., Mukhanov, O. A.
Format Journal Article
LanguageEnglish
Published New York IEEE 01.06.2013
The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:We investigate a Magnetic Josephson Junction (MJJ) - a superconducting device with ferromagnetic barrier for a scalable high-density cryogenic memory compatible with energy-efficient single flux quantum (SFQ) circuits. The superconductor-insulator-superconductor-ferromagnet-superconductor (SIS ' FS) MJJs are analyzed both experimentally and theoretically. We found that the properties of SIS ' FS junctions fall into two distinct classes based on the thickness of S ' layer. We fabricate Nb-Al/AlOx-Nb-PdFe-Nb SIS ' FS MJJs using a co-processing approach with a combination of HYPRES and ISSP fabrication processes. The resultant SIS ' FS structure with thin superconducting S ' -layer is substantially affected by the ferromagnetic layer as a whole. We fabricate these type of junctions to reach the device compatibility with conventional SIS junctions used for superconducting SFQ electronics to ensure a seamless integration of MJJ-based circuits and SIS JJ-based ultra-fast digital SFQ circuits. We report experimental results for MJJs, demonstrating their applicability for superconducting memory and digital circuits. These MJJs exhibit I c R n product only ~ 30% lower than that of conventional SIS junctions co-produced in the same fabrication. Analytical calculations for these SIS ' FS structures are in a good agreement with the experiment. We discuss application of MJJ devices for memory and programmable logic circuits.
ISSN:1051-8223
1558-2515
DOI:10.1109/TASC.2012.2233270