1. Laboratory of Photomolecular Science; Institute of Chemical Sciences and Engineering; École Polytechnique Fédérale de Lausanne; 1015 Lausanne Switzerland
2. Institute of Materials Science of Seville; Spanish National Research Council-University of Seville; Av. Americo Vespucio 49 41092 Seville Spain
3. Laboratory of Photonics and Interfaces; Institute of Chemical Sciences and Engineering; École Polytechnique Fédérale de Lausanne; 1015 Lausanne Switzerland
4. Research Division; Panasonic Corporation; 1006 (Oaza Kadoma) Kadoma City Osaka 571-8501 Japan
5. Adolphe Merkle Institute; University of Fribourg; Ch. du. Musée 3 CH-1700 Fribourg Switzerland