Unconventional electronic Raman spectra of borocarbide superconductors

Borocarbide superconductors, which are thought to be conventional BCS-type superconductors, are not so conventional in several electronic Raman properties. Anisotropic gap-like features and finite scattering strength below the gap were observed for the RNi2B2C (R = Lu, Y) systems in our previous study.[1] The effects of Go-doping on the 2 Delta gap-like features and the finite scattering strength below and above the gap are studied in R = Lu (B = B-11) system. In superconducting states, Go-doping strongly suppresses the 2 Delta peak in both B-2g and B-1g symmetries. Raman cross-section calculation which includes inelastic scattering shows a relatively good fit to the features above the 2 Delta peak, while it does not fully account for the features below the peak.