Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8158623 | Journal of Magnetism and Magnetic Materials | 2013 | 7 Pages |
Abstract
The magnetic and electrical properties of Ni implanted single crystalline TiO2 rutile were studied for nominal implanted fluences between 0.5Ã1017Â cmâ2 and 2.0Ã1017Â cmâ2 with 150Â keV energy, corresponding to maximum atomic concentrations between 9Â at% and 27Â at% at 65Â nm depth, in order to study the formation of metallic oriented aggregates. The results indicate that the as implanted crystals exhibit superparamagnetic behavior for the two higher fluences, which is attributed to the formation of nanosized nickel clusters with an average size related with the implanted concentration, while only paramagnetic behavior is observed for the lowest fluence. Annealing at 1073Â K induces the aggregation of the implanted nickel and enhances the magnetization in all samples. The associated anisotropic behavior indicates preferred orientations of the nickel aggregates in the rutile lattice consistent with Rutherford backscattering spectrometry-channelling results. Electrical conductivity displays anisotropic behavior but no magnetoresistive effects were detected.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
M.M. Cruz, R.C. da Silva, J.V. Pinto, R.P. Borges, N. Franco, A. Casaca, E. Alves, M. Godinho,