1. Faculty
of Mathematics and Physics, University of Ljubljana, Jadranska
19, SI 1000 Ljubljana, Slovenia
2. J. Stefan Institute, Jamova
39, SI 1000 Ljubljana, Slovenia
3. National Institute for Chemistry, Hajdrihova 19, SI 1001, Ljubljana, Slovenia
4. Polymer Technology College, SI2380 Slovenj Gradec, Slovenia
5. The
MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Applied
Physics Institute and School of Physics, Nankai University, Hongda
Street 23, Tianjin 300457, China