1. Université de Genève, GAP-Biophotonics, Chemin de Pinchat 22, 1211 Geneva 4, Switzerland.
2. Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
3. Université de Genève, GAP-Nonlinear, Chemin de Pinchat 22, 1211 Geneva 4, Switzerland.