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arXiv · 0806.1456

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

N. L. Bobrov·V. N. Chernobay·Yu. G. Naidyuk·L. V. Tyutrina·D. G. Naugle·K. D. D. Rathnayaka·S. L. Bud`ko·P. C. Canfield·I. K. Yanson
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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.

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N. L. Bobrov, V. N. Chernobay, Yu. G. Naidyuk, L. V. Tyutrina, D. G. Naugle, K. D. D. Rathnayaka, S. L. Bud`ko, P. C. Canfield, I. K. Yanson. 2008-06-09. Competition of multiband superconducting and magnetic order in ErNi2B2C observed by Andreev reflection. https://doi.org/10.1209/0295-5075/83/37003

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