Point-contact spectroscopy of the nickel borocarbide superconductors RNi2B2C (R=Y, Dy, Ho, Er, Tm, Lu) Academic Article uri icon

abstract

  • An overview of the recent efforts in point-contact (PC) spectroscopy of the nickel borocarbide superconductors RNi2B2C in the normal and superconducting (SC) state is given. The results of measurements of the PC electron-boson(phonon) interaction spectral function are presented. Phonon maxima and crystalline-electric-field (CEF) excitations are observed in the PC spectra of compounds with R = Dy, Ho, Er and Tm, while for R = Y a dominant phonon maximum around 12 meV is characteristic. Additionally, non-phonon and non-CEF maxima are observed near 3 meV in R = Ho and near 6 meV in R = Dy. Directional PC study of the SC gap gives evidence for the multi-band nature of superconductivity in R = Y, Lu. At low temperature the SC gap in R = Ho exhibits a standard single-band BCS-like dependence, which vanishes above Tc* 5.6 K < Tc 8.5 K, where a specific magnetic ordering starts to play a role. For R = Tm (Tc 10.5 K) a decrease of the SC gap is observed below 5 K. 2007 Elsevier B.V. All rights reserved.

published proceedings

  • Physica C: Superconductivity and its Applications

author list (cited authors)

  • Naidyuk, Y. G., Bashlakov, D. L., Bobrov, N. L., Chernobay, V. N., Kvitnitskaya, O. E., Yanson, I. K., ... Ross, J. H.

publication date

  • January 1, 2007 11:11 AM