Study for superconducting proximity effect in unconventional superconductivity by microscopic experimental probe

2015 Fiscal Year Final Research Report

• Project/Area Number: 25610082
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Hokkaido University
• Principal Investigator: Ihara Yoshihiko 北海道大学, 理学(系)研究科(研究院), 講師 (80598491)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 超伝導 / 核磁気共鳴 / 近接効果

Outline of Final Research Achievements

We have performed the nuclear magnetic resonance (NMR) experiment on the thin film deposited on the surface of unconventional superconductors to study the superconducting proximity effect. We prepared the superconductor-metal junction with various film thicknesses, and measured the nuclear spin-lattice relaxation rate for each sample. As the result, we found the increase or decrease in relaxation rate below the superconducting transition temperature. This result proves that the superconductivity proximity effect on one layer of thin film can be detected by the NMR experiment. We also found that whether the relaxation rate increase or decrease depends on the film thickness. Namely, the increase in relaxation rate observed in a sample with thin layer addresses an exotic characteristic of unconventional superconductivity. Further detailed experiments to confirm this behavior is now in progress.

Free Research Field

固体電子物性