Abstract
We have measured upper-critical-field (formula presented) specific heat C, and tunneling spectra of the intermetallic perovskite superconductor (formula presented) with a superconducting transition temperature (formula presented) Based on these measurements and relevant theoretical relations, we have evaluated various superconducting parameters for this material, including the thermodynamic critical field (formula presented) coherence length (formula presented) penetration depth (formula presented) lower-critical-field (formula presented) and Ginzburg-Landau parameter (formula presented) From the specific heat, we obtain the Debye temperature (formula presented) We find a jump of (formula presented) at (formula presented) (where (formula presented) is the normal-state electronic specific coefficient), which is larger than the weak-coupling BCS value of 1.43, suggesting that (formula presented) may be a strong-coupling superconductor. In addition, we observed a pronounced zero-bias conductance peak (ZBCP) in the tunneling spectra. We discuss the possible physical origins of the observed ZBCP.
Original language | English (US) |
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Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 67 |
Issue number | 9 |
DOIs | |
State | Published - Mar 13 2003 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics