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Effect of Ga$^{+}$ irradiation on magnetic and magnetotransport properties in (Ga,Mn)As epilayers

H. Kato·K. Hamaya·Y. Kitamoto·T. Taniyama·H. Munekata
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Abstract

We report on the magnetic and magnetotransport properties of ferromagnetic semiconductor (Ga,Mn)As modified by Ga$^{+}$ ion irradiation using focused ion beam. A marked reduction in the conductivity and the Curie temperature is induced after the irradiation. Furthermore, an enhanced negative magnetoresistance (MR) and a change in the magnetization reversal process are also demonstrated at 4 K. Raman scattering spectra indicate a decrease in the concentration of hole carriers after the irradiation, and a possible origin of the change in the magnetic properties is discussed.

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H. Kato, K. Hamaya, Y. Kitamoto, T. Taniyama, H. Munekata. 2004-10-01. Effect of Ga$^{+}$ irradiation on magnetic and magnetotransport properties in (Ga,Mn)As epilayers. https://doi.org/10.1063/1.1844751

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