Field dependence of the thermal conductivity in the iron-based superconductor KFe$_2$As$_2$

ORAL

Abstract

The behavior of the thermal conductivity in the iron-arsenide KFe$_2$As$_2$ at low temperature provides compelling evidence of d-wave superconductivity [1]. Here we report a detailed study of the thermal conductivity in KFe$_2$As$_2$ as a function of magnetic field, for two field orientations: perpendicular and parallel to the FeAs planes. The data are in excellent quantitative agreement with theoretical calculations for a d-wave superconductor [2]. Our study also highlights the power of thermal conductivity as a technique to directly measure the upper critical field H$_{c2}$ in a clean type-II superconductor. \\[4pt] [1] J.-Ph. Reid et al., Phys. Rev. Lett. 109, 087001 (2012).\\[0pt] [2] A. B. Vorontsov and I. Vekhter, Phys. Rev. B 75, 224502 (2007).

Authors

  • A. Juneau-Fecteau

    University of Sherbrooke

  • F.F. Tafti

    University of Sherbrooke

  • S. Ren\'e de Cotret

    University of Sherbrooke

  • N. Doiron-Leyraud

    University of Sherbrooke

  • L. Taillefer

    University of Sherbrooke, University of Sherbrooke (Canada)

  • X.H. Chen

    University of Science and Technology of China, Hefei National laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China

  • X.G. Luo

    University of Science and Technology of China

  • X.H. Chen

    University of Science and Technology of China, Hefei National laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China