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Thermal activation between Landau levels in the organic superconductor $β''$-(BEDT-TTF)$_{2}$SF$_{5}$CH$_{2}$CF$_{2}$SO$_{3}$

M. -S. Nam·A. Ardavan·J. A. Symington·J. Singleton·N. Harrison·C. H. Mielke·J. A. Schlueter·R. W. Winter·G. L. Gard
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Abstract

We show that Shubnikov-de Haas oscillations in the interlayer resistivity of the organic superconductor $β''$-(BEDT-TTF)$_{2}$SF$_{5}$ CH$_{2}$CF$_{2}$SO$_{3}$ become very pronounced in magnetic fields $\sim$~60~T. The conductivity minima exhibit thermally-activated behaviour that can be explained simply by the presence of a Landau gap, with the quasi-one-dimensional Fermi surface sheets contributing negligibly to the conductivity. This observation, together with complete suppression of chemical potential oscillations, is consistent with an incommensurate nesting instability of the quasi-one-dimensional sheets.

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M. -S. Nam, A. Ardavan, J. A. Symington, J. Singleton, N. Harrison, C. H. Mielke, J. A. Schlueter, R. W. Winter, G. L. Gard. 2001-05-02. Thermal activation between Landau levels in the organic superconductor $β''$-(BEDT-TTF)$_{2}$SF$_{5}$CH$_{2}$CF$_{2}$SO$_{3}$. https://doi.org/10.1103/physrevlett.87.117001

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