1. Institut des Molécules et Matériaux du Mans (IMMM-UMR CNRS 6283), Université du Mans, Avenue Olivier Messiaen, 72085 Le Mans CEDEX 9, France
2. Group of Optics, Department of Applied Physics, University of Cantabria, 39005 Santander, Spain
3. Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, Treboniu Laurian 42, 400271 Cluj-Napoca, Romania
4. Biomolecular Physics Department, Faculty of Physics, Babes-Bolyai University, Mihail Kogalniceanu No. 1, 400084 Cluj-Napoca, Romania