Anisotropic zero-resistance onset in organic superconductors

Vladislav D. Kochev; Kaushal K. Kesharpu; Pavel D. Grigoriev

doi:10.1103/physrevb.103.014519

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arXiv · 2007.14388

Anisotropic zero-resistance onset in organic superconductors

Vladislav D. Kochev·Kaushal K. Kesharpu·Pavel D. Grigoriev

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Abstract

We study the coexistence of superconductivity (SC) and density-wave state and reconcile various puzzling experimental data in organic superconductors (TMTSF)$_{2}$PF$_{6}$ and (TMTSF)$_{2}$ClO$_{4}$. The anisotropic resistance drop above $T_c$ is qualitatively described by nascent isolated SC islands within a bulk analytical model. However, the observed anisotropic SC onset is explained only when the finite size and flat needle shape of samples is considered. Our results pave a way to estimate the volume fraction and the typical size of SC islands in far from the sample surface, and apply to many inhomogeneous superconductors, including high-$T_c$ cuprate or Fe-based ones.

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Vladislav D. Kochev, Kaushal K. Kesharpu, Pavel D. Grigoriev. 2020-07-28. Anisotropic zero-resistance onset in organic superconductors. https://doi.org/10.1103/physrevb.103.014519

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