1. IQFR - CSIC, Serrano 119, 28006 Madrid,
Spain
2. Laboratoire de Physique
des
Solides, Bâtiment 510, CNRS UMR 8502, Université Paris Sud XI, F 91405 Orsay, France
3. Laboratoire Matériaux
et
Phénomènes Quantiques, CNRS-UMR 7162, Université Paris Diederot - Paris 7, Case Courrier 7021, 75205
Paris Cedex 13, France
4. Optoelectronics Research Centre
and Centre for Photonic Metamaterials, University of Southampton, Southampton SO17 1BJ, United Kingdom
5. Research Center in Physics of
Matter and Radiation (PMR), University of Namur (FUNDP), 61 rue de Bruxelles, 5000 Namur, Belgium
6. Departamento de Química
Física, Universidade de Vigo, 36310
Vigo, Spain