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Effect of the shape anisotropy on the magnetic configuration of (Ga,Mn)As and its evolution with temperature

K. Hamaya·T. Taniyama·T. Koike·Y. Yamazaki
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Abstract

We study the effect of the shape anisotropy on the magnetic domain configurations of a ferromagnetic semiconductor (Ga,Mn)As/GaAs(001) epitaxial wire as a function of temperature. Using magnetoresistance measurements, we deduce the magnetic configurations and estimate the relative strength of the shape anisotropy compared with the intrinsic anisotropies. Since the intrinsic anisotropy is found to show a stronger temperature dependence than the shape anisotropy, the effect of the shape anisotropy on the magnetic domain configuration is relatively enhanced with increasing temperature. This information about the shape anisotropy provides a practical means of designing nanostructured spin electronic devices using (Ga,Mn)As.

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K. Hamaya, T. Taniyama, T. Koike, Y. Yamazaki. 2006-03-06. Effect of the shape anisotropy on the magnetic configuration of (Ga,Mn)As and its evolution with temperature. https://doi.org/10.1063/1.2196113

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