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arXiv · 1212.4954

First-Order Superconducting Transition of Sr2RuO4

Shingo Yonezawa·Tomohiro Kajikawa·Yoshiteru Maeno
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Abstract

By means of the magnetocaloric effect, we examine the nature of the superconducting-normal (S-N) transition of Sr2RuO4, a most promising candidate for a spin-triplet superconductor. We provide thermodynamic evidence that the S-N transition of this oxide is of first order below approximately 0.8 K and only for magnetic field directions very close to the conducting plane, in clear contrast to the ordinary type-II superconductors exhibiting second-order S-N transitions. The entropy release across the transition at 0.2 K is 10% of the normal-state entropy. Our result urges an introduction of a new mechanism to break superconductivity by magnetic field.

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Shingo Yonezawa, Tomohiro Kajikawa, Yoshiteru Maeno. 2012-12-20. First-Order Superconducting Transition of Sr2RuO4. https://doi.org/10.1103/physrevlett.110.077003

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