ISSN:
1434-6036
Keywords:
PACS. 61.80.Jh Ion radiation effects – 75.60.-d Domain effects, magnetization curves, and hysteresis – 85.70.Ge Ferrite and garnet devices
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: The behavior of the magnetic properties of magnetite Fe3O4 irradiated by swift heavy ions is investigated by magnetization measurements. Although there is no induced structural phase transformation, both coercive field and saturation magnetization are sensitive to ion irradiation and exhibit different behaviors depending on the ion fluence range. In the low fluence regime, the coercive field increases, which is evidence for a strong pinning of magnetic domain boundaries by the induced defects. The magnetization shows a decrease in the saturation value and tends to reorient perpendicularly to the ion track axis. At high fluence, the initial magnetic properties of the sample are nearly restored. The changes in the magnitude and the direction of magnetization are interpreted by magnetostrictive effects related to the stress induced by irradiation. A phenomenological model is applied to reproduce the fluence evolution of the saturation magnetization, assuming relaxation of the stress induced around the core of defects of the tracks by overlapping effects at high fluence. The results are compared to those obtained in the case of yttrium iron garnet Y3Fe5O12.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s10051-001-8676-3
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