| Autor: |
Ney, V., Ye, S., Kammermeier, T., Ney, A., Zhou, H., Fallert, J., Kalt, H., Lo, F.-Y., Melnikov, A., Wieck, A. D. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; Oct2008, Vol. 104 Issue 8, p083904, 6p, 8 Graphs |
| Abstrakt: |
ZnO(0001) substrates were ion implanted with 100 keV of Co and 300 keV of Gd at different fluences ranging from 5×1013–1×1015/cm2. The resulting Co:ZnO and Gd:ZnO samples were analyzed with respect to their structural, magnetic, and optical properties. The effect of annealing at 350 °C on the structure and the resulting magnetic and optical properties were investigated as well. For Co:ZnO hardly any changes were observable, neither in the structural nor in the magnetic properties, even though the existence of substitutional Co2+ in the ZnO lattice could be shown by means of low temperature photoluminescence especially for Zn-annealed samples. For the much larger Gd ion the implantation leads to a changed crystal structure, which leads to a ferromagneticlike behavior for higher implantation doses, which could even be enhanced by annealing in vacuum. Ferromagnetic behavior in annealed Gd:ZnO is corroborated by ferromagnetic resonance measurements at low temperatures. The distinct behavior of Gd- and Co-implanted ZnO highlights the importance of defects in the understanding of the magnetic properties in dilute magnetic semiconductors. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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