1. Materials Research Laboratory, University of Nova Gorica, Vipavska 11c, 5270 Ajdovščina, Slovenia
2. Laboratory of Organic Matter Physics, University of Nova Gorica, Vipavska 11c, 5270 Ajdovščina, Slovenia
3. Laboratory of Quantum Optics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
4. Department of Low and Medium Energy Physics, J. Stefan Institute, Jamova 39, POB 000, SI-1001 Ljubljana, Slovenia
5. Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, 610054 Chengdu, China