1. National
Institute of Optics, National Council of Research of Italy, Via
Campi Flegrei 34, 80078 Pozzuoli, Italy
2. Institute
of Microelectronics and Microsystems, National Council of Research of Italy, Via Pietro Castellino, Napoli, Italy
3. Institute
of Polymer Chemistry and Technology, National Council of Research of Italy, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
4. Department
of Chemical, Materials and Production Engineering, University of Naples, Piazzale Tecchio, 80125 Naples, Italy