Quantum Dot coupled to a normal and a superconducting lead
  We report on electrical transport measurements in a carbon nanotube quantum dot coupled to a normal and a superconducting lead. Depending on the ratio of Kondo temperature $T_{K}$ and superconducting gap $\Delta$ the zero bias conductance resonance either is split into two side-peaks or persists. We also compare our data with a simple model of a resonant level - superconductor interface. 
M.R. Graeber, T. Nussbaumer, W. Belzig and C. Schoenenberger