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Anomalous behaviour of the in-plane electrical conductivity of the layered superconductor $κ$-(BEDT-TTF)$_2$Cu(NCS)$_2$

John Singleton·Charles Mielke·William Hayes·John Schlueter
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Abstract

The quasiparticle scattering rates in high-quality crystals of the quasi-two-dimensional superconductor $κ$-(BEDT-TTF)$_2$Cu(NCS)$_2$ ~are studied using the Shubnikov-de Haas effect and MHz penetration-depth experiments. There is strong evidence that the broadening of the Landau-levels is primarily caused by spatial inhomogeneities, indicating a quasiparticle lifetime for the Landau states $\gg 3$ ps. In contrast to the predictions of Fermi-liquid theory, the scattering time derived from the intralayer conductivity is found to be much shorter ($0.14-0.56$ ps).

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John Singleton, Charles Mielke, William Hayes, John Schlueter. 2003-08-07. Anomalous behaviour of the in-plane electrical conductivity of the layered superconductor $κ$-(BEDT-TTF)$_2$Cu(NCS)$_2$. https://doi.org/10.1088/0953-8984%2F15%2F12%2F103

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