Tunneling measurements of the electron spectrum in the superconducting state have been carried out in Y2C3 samples with the bulk (resistive and diamagnetic) critical temperature Tc = 15-16 K. A break-junction technique was crucial to find the intrinsic gap features. The representative gap structure at 4 K reveals distinct BCS-like peaks with the gap value of 2Δ(4 K) = 3-4 meV. Assuming local Tc values of 10-13 K, the characteristic gap to Tc ratio 2Δ/kBT c (kB is the Boltzmann constant) was found to possess the BCS weak-coupling value 3.5 ± 0.2, appropriate to isotropic s-wave superconductors.
- Break junction
- Superconducting energy gap
ASJC Scopus subject areas
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Energy Engineering and Power Technology
- Electronic, Optical and Magnetic Materials