Influence of surface anisotropy on the magnetization reversal of nanoparticles
نویسنده
چکیده
The influence of surface anisotropy on the magnetization processes of maghemite nanoparticles with ellipsoidal shape is studied by means of Monte Carlo simulations. Radial surface anisotropy is found to favor the formation of hedgehog-like spin structures that become more stable as the surface anisotropy constant at the surface kS is increased form the value at the core. We have studied the change in the low temperature hysteresis loops with the particle aspect ratio and with kS , finding a change in the magnetization reversal mode as kS or the particle elongation is increased.
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