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Negative magnetoresistance and anomalous Hall effect in GeMnTe-SnMnTe spin-glass-like system

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 نشر من قبل Kilanski Lukasz Dr.
 تاريخ النشر 2012
  مجال البحث فيزياء
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Magnetotransport properties of spin-glass-like Ge/1-x-y/Sn/x/Mn/y/Te mixed crystals with chemical composition changing in the range of 0.083 < x < 0.142 and 0.012 < y < 0.119 are presented. The observed negative magnetoresistance we attribute to two mechanisms i.e. weak localization occurring at low fields and spin disorder scattering giving contribution mainly at higher magnetic fields. A pronounced hysteretic anomalous Hall effect (AHE) was observed. The estimated AHE coefficient shows a small temperature dependence and is dependent on Mn-content, with changes in the range of 10E-7 < R_S < 10E-6 m^3/C. The scaling law analysis has proven that the AHE in this system is due to the extrinsic mechanisms, mainly due to the skew scattering accompanied with the side jump processes.

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