2010/06/30 by A. P. Petrović, R. Lortz, Rolf Lortz +13 · 46 citations
Materials Science · Physics and Astronomy · #Anisotropy #Condensed matter physics #Iron-based superconductors research #Materials science #Optics #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Spectral line #Spectroscopy #Superconductivity #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.106.017003
published in Physical Review Letters 106(1), 017003 (American Physical Society) · 5 pages, 4 figures
arxiv created 2010/06/30 · openalex publication_date 2011/01/06 · arxiv updated 2013/03/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Sub-Kelvin scanning tunneling spectroscopy in the Chevrel phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with \ensuremathΔ1=3 meV, \ensuremathΔ2\ensuremath∼1.0 meV and \ensuremathΔ1=3.1 meV, \ensuremathΔ2\ensuremath∼1.4 meV, respectively. The gap distribution is strongly anisotropic, with \ensuremathΔ2 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.