119Sn NMR study in the normal state of the superconductor Ca3Ir4Sn13
1 Hangzhou Key Laboratory of Quantum Matter, Department of Physics, Hangzhou Normal University Hangzhou 310036, China
2 Department of Chemistry, Graduate School of Science, Kyoto University - Kyoto 606-8502, Japan
Received: 9 March 2015
Accepted: 4 July 2015
We report a 119Sn nuclear magnetic resonance (NMR) investigation of Ca3Ir4Sn13 with superconducting transition temperature . The anomaly observed at in susceptibility and resistivity has been successfully identified by both Knight shift K and the temperature-divided spin lattice relaxation rate, . Detailed analysis indicates that the hyperfine coupling constant changes at , suggesting the variation of the electronic states with temperature approaching 45 K. Furthermore, shows a linear behavior with magnetic susceptibility χ above , indicating the existence of three-dimensional ferromagnetic spin fluctuations in the normal state of Ca3Ir4Sn13 above 45 K. The relation between spin fluctuations and superconductivity is discussed.
PACS: 74.70.-b – Superconducting materials other than cuprates / 76.60.-k – Nuclear magnetic resonance and relaxation
© EPLA, 2015