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arXiv · 1006.5956

Multi-band Superconductivity in the Chevrel Phases SnMo6S8 and PbMo6S8

A. P. Petrović·R. Lortz·G. Santi·C. Berthod·C. Dubois·M. Decroux·A. Demuer·A. B. Antunes·A. Paré·D. Salloum·P. Gougeon·M. Potel·Ø. Fischer
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Abstract

Sub-Kelvin scanning tunnelling spectroscopy in the Chevrel Phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with Delta_1 = 3 meV, Delta_2 ~ 1.0 meV and Delta_1 = 3.1 meV, Delta_2 ~ 1.4 meV respectively. The gap distribution is strongly anisotropic, with Delta_2 predominantly seen when scanning across unit-cell steps on the (001) sample surface. The spectra are well-fitted by an anisotropic two-band BCS s-wave gap function. Our spectroscopic data are confirmed by electronic heat capacity measurements which also provide evidence for a twin-gap scenario.

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A. P. Petrović, R. Lortz, G. Santi, C. Berthod, C. Dubois, M. Decroux, A. Demuer, A. B. Antunes, A. Paré, D. Salloum, P. Gougeon, M. Potel, Ø. Fischer. 2010-06-30. Multi-band Superconductivity in the Chevrel Phases SnMo6S8 and PbMo6S8. https://doi.org/10.1103/physrevlett.106.017003

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