Dynamically current-driven de Gennes -St James states in Metal-Superconductor junctions

Hervé Cercellier (1) , Hadrien Grasland (1) , H.Q. Luo (2) , X.Y. Lu (2) , D.L. Gong (2) , Z.-S. Wang (1, 2) , Thierry Klein (1)

1 NEEL - MagSup - Magnétisme et Supraconductivité
2 beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science

We investigate the conductance of a Normal-Normal'-Superconductor (NN'S) junction, in which current injection destroys superconductivity in a small region N' of the superconductor, with a size varying with the applied voltage V. Voltage-dependent de Gennes-Saint James (dGSJ) bound states appearing in the N' slab lead to two distinct sets of conductance oscillations. We show that this effect significantly alters the conductance of systems for which κ 2 vF ∼ 10 9 m/s such as pnictides (κ and vF being the Ginzburg number and the Fermi velocity, respectively), and we discuss their consequences on the identification of the bosonic modes of strongly coupled superconductors.

Domaines: Supraconductivité [cond-mat.supr-con]

Hervé Cercellier, Hadrien Grasland, H.Q. Luo, X.Y. Lu, D.L. Gong, et al.. Dynamically current-driven de Gennes -St James states in Metal-Superconductor junctions. 2016. ⟨hal-01308180⟩