| speaker: | Jens Paaske Niels Bohr Instituttet & Nano-Science Centret, Copenhagen, Denmark |
| time: | Tu., 21.08, 14:50-15:40 |
Collaborators: T. Sand-Jespersen, B. M. Andersen, K. Grove-Rasmussen, H. I. Jorgensen, M. Aagesen, C. Sorensen, P. E. Lindelof, K. Flensberg, J. Nygaard at the Niels Bohr Institute in Copenhagen.
We report measurements of the nonlinear conductance of InAs nanowire quantum dots coupled to superconducting leads. We observe a clear alternation between odd and even occupation of the dot, with sub-gap-peaks at |V_{sd}|=Delta/e markedly stronger(weaker) than the quasiparticle tunneling peaks at |V_{sd}|=2Delta/e for odd(even) occupation. We attribute the enhanced \Delta-peak to an interplay between Kondo-correlations and Andreev tunneling in dots with an odd number of spins, and substantiate this interpretation by a poor man's scaling analysis.