Studies on two-gap superconductivity in 2H-NbS(2)

J. Kacmarcik (1) , Z. Pribulova , C. Marcenat (2) , T. Klein (3) , P. Rodiere , Laurent Cario (4) , P. Samuely

1 CLTP IEP - Centre of Low Temperature Physics
2 SPSMS - UMR 9001 - Service de Physique Statistique, Magnétisme et Supraconductivité
3 MPIFR - Max-Planck-Institut für Radioastronomie
4 IMN - Institut des Matériaux Jean Rouxel

We present the ac-calorimetry measurements of superconducting 2H-NbS2 in the temperature range down to 0.6 K and magnetic fields up to 8 T. The temperature and magnetic field dependence of the electronic specific heat consistently indicate existence of two superconducting energy gaps in the system - one of them with the coupling ratio below the BCS weak-coupling limit and the other above that value. These results support previous findings by scanning tunneling microscopy and spectroscopy measurements [I. Guillamón, H. Suderow, S. Vieira, L. Cario, et al., Phys. Rev. Lett. 101 (2008) 166407] of two pronounced features in density of states related to a two-gap superconductivity in this system.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

J. Kacmarcik, Z. Pribulova, C. Marcenat, T. Klein, P. Rodiere, et al.. Studies on two-gap superconductivity in 2H-NbS(2). Physica C: Superconductivity and its Applications, 2010, 470, pp.S719. ⟨10.1016/j.physc.2009.10.131⟩. ⟨hal-00849336⟩