1. Physics Department, University of Calabria, Ponte P. Bucci, Cubo 33B, 87036 Rende (CS), Italy
2. CNR-NANOTEC UOS Cosenza, LiCryL and Centre of Excellence CEMIF.CAL, Ponte P. Bucci, Cubo 33B, 87036 Rende (CS), Italy
3. Department of Mechanical, Energy and Management Engineering, Ponte P. Bucci, Cubo 46 C, 87036 Rende (CS), Italy