1. a Department of Mechanical Engineering , EST/IPS , Campus do IPS , Estefanilha, 2910‐761 Setúbal, Portugal
2. b I3N – CENIMAT , Quinta da Torre , 2829‐516 Caparica, Portugal
3. c Department of Materials Science , The New University of Lisbon , 2829‐516 Caparica, Portugal
4. d CFMC – UL , Av. Prof. Gama Pinto 2, 1649‐003 Lisboa, Portugal
5. e Department of Physics , IST , Av. Rovisco Pais, 1049‐001 Lisboa, Portugal