Abstract
We have measured the optical reflectivity of LuNC and YNC compounds, and have evaluated the optical conductivity both below and above the superconducting transition temperature. The normal state optical properties suggest that these superconductors are almost in the clean limit. Our results below give, however, evidence of a superconducting gap signature, and are in agreement with a BCS singlet ground state. Our experimental findings also indicate a moderate-to-strong coupling limit for the pairing mechanism.
- Received 2 July 1996
DOI:https://doi.org/10.1103/PhysRevLett.78.547
©1997 American Physical Society