1. School of Science and Technology Physics Section University of Camerino, Via Madonna delle Carceri 9, 62032 Camerino, MC, Italy
2. Dipartimento di Scienze Fisiche e Chimiche (DSFC), Università degli Studi dell'Aquila, Via Vetoio 10, 67100 L'Aquila, Italy
3. Istituto di Struttura della Materia-CNR (ISM-CNR), S.S. 14, Km 163,5, 34149 Trieste, Italy
4. Faculty of Applied Physics and Mathematics, and Advanced Materials Centre, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
5. Department of Physics, Division of Science and Technology, University of Education Lahore, Jauharabad Campus, Pakistan
6. CNR-SPIN UoS L' Aquila, Via Vetoio 10, 67100 L'Aquila, Italy
7. INFN-Sez. Perugia, Via Pascoli Perugia, Italy