Berlin 2012 – wissenschaftliches Programm
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MA: Fachverband Magnetismus
MA 39: Micro- and Nanostructured Magnetic Materials I
MA 39.6: Vortrag
Donnerstag, 29. März 2012, 10:45–11:00, EB 202
Defect-induced ferromagnetism in SiC — •Yutian Wang1, Lin Li1, Slawomir Prucnal1, Kay Potzger1, Shengqiang Zhou1, Zhaorong Yang2, Wolfgang Anwand3, and Andreas Wagner3 — 1Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, POB 51 01 19, 01314 Dresden, Germany — 2Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China — 3Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, POB 51 01 19, 01314 Dresden, Germany
A controllable method to create defects in SiC is the key requirement for understanding the mechanism of the defect-induced ferromagnetism. Using Ne-ion irradiation, defect-induced ferromagnetism in SiC can be established. Electron-spin resonance and positron annihilation spectroscopy [1] are adopted to determine the location of unpaired electrons and the type of defects. The dependence of magnetic properties on the concentrations of VSi-VC divacancies has been studied. We found that by increasing the irradiation fluence the saturation magnetization has increased initially, then dropped to almost zero since a large irradiation fluence induced too much disorder [2]. Temperature dependent magnetization indicates two ferromagnetic components. One reveals a Curie temperature around 70 K while another one has a Curie temperature above room temperature. Employing electron-spin resonance and SQUID magnetometry leads to the observation of large magnetic anisotropy. Reference: 1.Brauer, G., et al., Phys. Rev. B, 54, 3084 (1996). 2.Li, L. et al., Appl. Phys. Lett., 98, 222508 (2011).