Competition of multiband superconducting and magnetic order in ErNi2B2C observed by Andreev reflection

Abstract

Point contacts (PC) Andreev reflection dV/dI spectra for the antiferromagnetic (T_N =6K) superconductor (Tc=11K) ErNi2B2C have been measured for the two main crystallographic directions. Observed retention of the Andreev reflection minima in dV/dI up to Tc directly points to unusual superconducting order parameter (OP) vanishing at Tc. Temperature dependence of OP was obtained from dV/dI using recent theory of Andreev reflection including pair-breaking effect. For the first time existence of a two superconducting OPs in ErNi2B2C is shown. A distinct decrease of both OPs as temperature is lowered below T_N is observed.

5 pages, 5 figs, to be published in Europhys. Lett

References in corpus (5)

• Upper critical field pecularities of superconducting YNi2B2C and LuNi2B2C
• Local superconducting density of states of ErNi2B2C
• Point Contact Spectroscopy of Superconducting Gap Anisotropy in Nickel Borocarbide Compound LuNi2B2C
• Bulk electronic structure of the antiferromagnetic superconducting phase in ErNi2B2C
• Investigation of the superconducting energy gap in the compound LuNi${}_2$B${}_2$C by the method of point contact spectroscopy: two-gap approximation

Cited by in corpus (7)

• Probing multiband superconductivity by point-contact spectroscopy
• Anatomy of point-contact Andreev reflection spectroscopy from the experimental point of view (review)
• Peculiarities of the superconducting gaps and the electron-boson interaction in TmNi2B2C as seen by point-contact spectroscopy
• Non-collinear order and gapless superconductivity in s-wave magnetic superconductors
• Observation of anisotropic effect of antiferromagnetic ordering on the superconducting gap in ErNi2B2C
• Inelastic electron-phonon scattering and excess current in superconducting point contacts with a short coherence length
• Nonequilibrium effects in ballistic point contacts Ta-Cu and 2H-NbSe2-Cu. Two-gap superconductivity in 2H-NbSe2