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arXiv · 0905.2342

Location of gap nodes in the organic superconductors $\kappa$-(ET)$_2$Cu(NCS)$_2$ and $\kappa$-(ET)$_2$Cu[N(CN)$_2$]Br determined by magnetocalorimetry

L. Malone·O. J. Taylor·J. A. Schlueter·A. Carrington
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Abstract

We report specific heat measurements of the organic superconductors $\kappa$-(ET)$_2$Cu(NCS)$_2$ and $\kappa$-(ET)$_2$Cu[N(CN)$_2$]Br. When the magnetic field is rotated in the highly conducting planes at low temperature ($T\simeq 0.4$ K), we observe clear oscillations of specific heat which have a strong fourfold component. The observed strong field and temperature dependence of this fourfold component identifies it as originating from nodes in the superconducting energy gap which point along the in-plane crystal axes ($d_{xy}$ symmetry)

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L. Malone, O. J. Taylor, J. A. Schlueter, A. Carrington. 2009-05-14. Location of gap nodes in the organic superconductors $\kappa$-(ET)$_2$Cu(NCS)$_2$ and $\kappa$-(ET)$_2$Cu[N(CN)$_2$]Br determined by magnetocalorimetry. https://doi.org/10.1103/physrevb.82.014522

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