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Unconventional electronic Raman spectra of borocarbide superconductors

In-Sang Yang·M. V. Klein·T. P. Devereaux·I. R. Fisher·P. C. Canfield
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Abstract

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 $R$Ni$_2$B$_2$C ($R$ = Lu, Y) systems in our previous study. The effects of Co-doping on the 2$Δ$ 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, Co-doping strongly suppresses the 2$Δ$ 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$Δ$ peak, while it does not fully account for the features below the peak.

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In-Sang Yang, M. V. Klein, T. P. Devereaux, I. R. Fisher, P. C. Canfield. 1999-12-31. Unconventional electronic Raman spectra of borocarbide superconductors. https://doi.org/10.1016/s0921-4534(00)01106-0

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