Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 18: Poster I : Bio Magn. (1-2); Mag.Imgaging (3-9); Magn. Semiconductors (10-16); Half Metals & Oxides (17-20); Coupl.Phenomena (21-27); Magn. Mat. (28-41); Micro & Nanostr. Magn. Materials (42-61); Micro Magn. (62-64); Surface Magnetism (65-70); Transport Phenomena (71-85)

MA 18.13: Poster

Dienstag, 26. Februar 2008, 15:15–18:30, Poster E

Investigations of different oxide diluted magnetic semiconductors — •Milan Gacic, Gerhard Jakob, and Hermann Adrian — Institut für Physik, Universität Mainz, Staudinger Weg 7, 55128 Mainz

Though many groups are working for years now on finding the origin of room temperature ferromagnetism in oxide diluted magnetic semiconductors as ZnO or TiO₂ doped with different transition metals, there is still no breakthrough in sight. The results are controversial and it is even not clear whether it is an intrinsic effect. However, the growth process and the growth conditions seem to play an important role.
We did extensive investigations on the wide bandgap semiconductors ZnO and ZrO₂ with different doping combinations. Here we present and compare our results concerning magnetic and transport properties of ZnO:Co, ZnO:(Co,Li), ZnO:C and ZrO₂:Mn thin films. All films were deposited by pulsed laser deposition on sapphire or ZrO₂ substrates at different growth conditions. The magnetic properties were extremely sensitive to the preparation condition. However, there is evidence that mostly defect rich films exhibit ferromagnetism. Most of the samples showed a small anomalous Hall effect as well as a clear and strongly temperature dependent magnetoresistance, which seems to be much more influenced by the doping than the magnetic properties.