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arXiv · 0806.4814

The Superconducting Gap Behavior in the Antiferromagnetic Nickel-Borocarbide Compounds RNi2B2C (R=Dy, Ho, Er, Tm) Studied by Point-Contacts Spectroscopy

Yu. G. Naidyuk·G. Behr·N. L. Bobrov·V. N. Chernobay·S. -L. Drechsler·G. Fuchs·O. E. Kvitnitskaya·D. G. Naugle·K. D. D. Rathnayaka·I. K. Yanson
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Abstract

An general survey of the superconducting (SC) gap study in the title compounds by point-contact (PC) spectroscopy is presented. The SC gap was determined from dV/dI of PCs employing the well-known theory of conductivity for normal metal-superconductor PCs accounting Andreev reflection. The theory was modified by including pair-breaking effects considering the presence of magnetic rare-earth ions. A possible multiband structure of these compounds was also taken into account. The PC study of the gap in the Er-compound (TN=6K Tc=6.5K) the SC gap has a BCS-like dependence in the AF state. The SC gap for R = Ho (TN=5.2K<Tc=8.5K) exhibits below T*=5.6K a single-band BCS-like dependence vanishing above T*, where a specific magnetic order occurs. The difference in the SC gap behavior in the title compounds is attributed to different AF ordering.

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Yu. G. Naidyuk, G. Behr, N. L. Bobrov, V. N. Chernobay, S. -L. Drechsler, G. Fuchs, O. E. Kvitnitskaya, D. G. Naugle, K. D. D. Rathnayaka, I. K. Yanson. 2008-07-02. The Superconducting Gap Behavior in the Antiferromagnetic Nickel-Borocarbide Compounds RNi2B2C (R=Dy, Ho, Er, Tm) Studied by Point-Contacts Spectroscopy. https://doi.org/10.1088/1742-6596/150/5/052178

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