Anisotropy of the Superconducting Gap of the Borocarbide Superconductor YNi2B2C with Ultrasonic Attenuation
Abstract
The ultrasonic attenuation α of the highly anisotropic s-wave superconductor YNi2B2C has been measured for all the symmetrically independent elastic modes to explore the location of the zero superconducting gap region on the Fermi surface. The attenuation of the longitudinal mode shows a pronounced anisotropy in the superconducting state: While α shows a thermally activated behavior along [110] and [001] directions, it shows T-linear dependence along [100]. These results together with those for the transverse modes demonstrate the presence of point nodes or zero-gap regions along [100] and [010] directions. This is a clear demonstration of ultrasonic attenuation as a powerful probe for the structure of the anisotropic superconducting gap.
- Publication:
-
Physical Review Letters
- Pub Date:
- April 2004
- DOI:
- 10.1103/PhysRevLett.92.147002
- Bibcode:
- 2004PhRvL..92n7002W
- Keywords:
-
- 74.25.Ld;
- 74.20.Rp;
- 74.25.Jb;
- 74.70.Dd;
- Mechanical and acoustical properties elasticity and ultrasonic attenuation;
- Pairing symmetries;
- Electronic structure;
- Ternary quaternary and multinary compounds