Detalhes bibliográficos
| Resumo: | Sapphire single crystals implanted with different fluences of cobalt and subjected to annealing treatments in vacuum and in air during 1 h at 1000 degreesC were studied by optical and structural techniques. At room temperature the absorption mainly occurs in the ultraviolet (UV) being the luminescence dominated by a UV/blue broad emission band and a highly structured red emission. Structural analysis indicates that metallic precipitates, CoAl2O4 and CoO phases are present in the implanted and annealed samples depending either on the fluence and on the annealing atmosphere. The observed luminescence cannot be correlated with intra-ionic Co2+ and Co3+ in an Al3+ site in the sapphire lattice and a tentative assignment of the observed emission lines to the presence of aggregates is made. |
| Autores principais: | Monteiro, T. |
| Outros Autores: | Soares, M.J.; Santos, L.; Boemare, C.; Cascalheira, J.; Alves, L.C.; Alves, E. |
| Assunto: | Precipitates a-Al2O3 Optical properties |
| Ano: | 2002 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso restrito |
| Instituição associada: | Universidade de Aveiro |
| Idioma: | inglês |
| Origem: | RIA - Repositório Institucional da Universidade de Aveiro |