1. Department of Physics; Chalmers University of Technology; SE41296 Göteborg Sweden
2. Department of Energy Engineering; Hanyang University; Seoul 04763 South Korea
3. Department of Pharmacy; “G. D'Annunzio” Chieti-Pescara University; Via Dei Vestini 31 Chieti Italy
4. CNR-ISC; U.O.S. Sapienza; Piazzale A. Moro 5 00185 Roma Italy