Proximity effect-induced superconductivity and NMR relaxation in Nb-Cu multilayers

Guo-Qing Zheng, Yoshio Kitaoka, Yasukage Oda, Kunisuke Asayama, Yoshihisa Obi, Hiroyasu Fujimori, Ryozo Aoki

Research output: Contribution to journalArticle

9 Citations (Scopus)


The nuclear spin lattice relaxation rate, T1-l, for 63Cu in zero field from 8 K down to 0.3 K, has been measured in Nb-Cu multilayered thin films where both the Nb- and Cu-layer thicknesses are much smaller compared to the coherence lengths. A BCS- like temperature dependence of T1-1 replaced gradually by a Korringa-law-like one at low temperatures has been found. A dependence of the relaxation on the Cu-layer thickness at low temperatures has also been found. It has been proposed and confirmed by a series of experiments that superconductivity in the Cu-layer induced by the proximity effect has an anisotropic energy gap, reflecting the geometrical feature of a thin film.

Original languageEnglish
Pages (from-to)599-607
Number of pages9
JournalJournal of the Physical Society of Japan
Issue number2
Publication statusPublished - Feb 1991
Externally publishedYes



  • Cu NMR
  • Energy gap
  • Nb-Cu
  • Spin-lattice relaxation rate
  • Superconducting multilayers
  • Superconducting proximity effect

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Zheng, G-Q., Kitaoka, Y., Oda, Y., Asayama, K., Obi, Y., Fujimori, H., & Aoki, R. (1991). Proximity effect-induced superconductivity and NMR relaxation in Nb-Cu multilayers. Journal of the Physical Society of Japan, 60(2), 599-607.