Quarterman, P orcid.org/0000-0001-6272-6243, Satchell, N orcid.org/0000-0003-1597-2489, Kirby, BJ orcid.org/0000-0003-2472-3791 et al. (4 more authors) (2020) Distortions to the penetration depth and coherence length of superconductor/normal-metal superlattices. Physical Review Materials, 4 (7). 074801. ISSN 2475-9953
Abstract
Superconducting (S) thin film superlattices composed of Nb and a normal-metal spacer (N) have been extensively utilized in Josephson junctions given their favorable surface roughness compared to Nb films of comparable thickness. In this work, we characterize the London penetration depth and Ginzburg-Landau coherence lengths of S/N superlattices using polarized neutron reflectometry and electrical transport. Despite the normal-metal spacer layers being only approximately 8% of the total superlattice thickness, we surprisingly find that the introduction of these thin N spacers between S layers leads to a dramatic increase in the measured London penetration depth compared to that of a single Nb film of comparable thickness. Using the measured values for the effective in- and out-of-plane coherence lengths, we quantify the induced anisotropy of the superlattice samples and compare to a single Nb film sample. From these results, we find that the superlattices behave similarly to layered 2D superconductors.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2020 American Physical Society. This is an author produced version of an article published in Physical Review Materials. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Condensed Matter (Leeds) |
Funding Information: | Funder Grant number EPSRC (Engineering and Physical Sciences Research Council) EP/M000923/1 EU - European Union 743791 |
Depositing User: | Symplectic Publications |
Date Deposited: | 15 Jul 2020 14:11 |
Last Modified: | 19 Dec 2024 15:19 |
Status: | Published |
Publisher: | American Physical Society |
Identification Number: | 10.1103/PhysRevMaterials.4.074801 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:163107 |