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arXiv · 0709.3172

Impurity Effect on Superconducting Properties in Molecular Substituted Organic Superconductor $κ$-(ET)$_2$Cu(NCS)$_2$

Naoki Yoneyama·Takahiko Sasaki·Hajime Oizumi·Norio Kobayashi
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Abstract

We report an impurity effect in the organic superconductor $κ$-(ET)$_2$Cu(NCS)$_2$ by substitution of the ET molecule with an analogue, bis(methyleneditio)tetrathiafulvalene (MT). The superconducting transition temperature decreases with increasing substitution. The in-plane magnetic penetration depth is enhanced with substitution, which is quantitatively attributed to the decrease in the in-plane mean free path. The enhancement of the penetration depth can also explain the reduction of the effective pinning in terms of the condensation energy.

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Naoki Yoneyama, Takahiko Sasaki, Hajime Oizumi, Norio Kobayashi. 2007-09-20. Impurity Effect on Superconducting Properties in Molecular Substituted Organic Superconductor $κ$-(ET)$_2$Cu(NCS)$_2$. https://doi.org/10.1143/jpsj.76.123705

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