1. UNESP - São Paulo State University; School of Sciences; POSMAT - Post-Graduate Program in Materials Science and Technology, Av. Eng. Luiz Edmundo Carrijo Coube 14-01; 17033-360, Bauru, SP Brazil
2. Federal University of Santa Catarina (UFSC); Department of Physics; Post-Graduate Program in Physics, Florianópolis, SC; 88040-900 Brazil
3. UNESP - São Paulo State University; School of Sciences; Department of Physics, Av. Eng. Luiz Edmundo Carrijo Coube 14-01; 17033-360 Bauru, SP Brazil