1. Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine, Lviv, Ukraine
2. Institute of Applied Mathematics and Fundamental Sciences, National Polytechnic University, Lviv, Ukraine
3. Center for Life Nano Science @Sapienza, Istituto Italiano di Tecnologia, Roma, Italy
4. Dipartimento di Fisica, Universita' di Roma “La Sapienza”, Roma, Italy