1. Faculty of Chemistry and Geosciences, Vilnius University, Vilnius LT-03225, Lithuania
2. Faculty of Physics, Vilnius University, Vilnius LT-10222, Lithuania
3. CNRS, IJL, Université de Lorraine, Epinal F-88000, France
4. Center for Physical Science and Technology, Vilnius LT-10257, Lithuania
5. Institute of Photonics, University of Eastern Finland, Joensuu FI-80101, Finland
6. Institut Universitaire de France (IUF), 75231 Paris Cedex 05, France