1. Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii
Street, UA-79011 Lviv, Ukraine
2. Institute
of Applied Mathematics and Fundamental Sciences, Lviv Polytechnic National University, UA-79013 Lviv, Ukraine
3. Istituto Nazionale di Ottica INO-CNR, I-50019 Sesto Fiorentino, Italy
4. European Laboratory for Non Linear Spectroscopy, LENS, I-50019 Sesto Fiorentino, Italy
5. Dipartimento
di Fisica, Universita di Roma La Sapienza, I-00185 Roma, Italy
6. Center
for Life Nano Science @Sapienza, Istituto Italiano di Tecnologia, 295 Viale Regina Elena, I-00161 Roma, Italy