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Weak localization in GaMnAs: evidence of impurity band transport

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 نشر من قبل Leonid Rokhinson
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report the observation of negative magnetoresistance in the ferromagnetic semiconductor GaMnAs at low temperatures ($T<3$ K) and low magnetic fields ($0< B <20$ mT). We attribute this effect to weak localization. Observation of weak localization provides a strong evidence of impurity band transport in these materials, since for valence band transport one expects either weak anti-localization due to strong spin-orbit interactions or total suppression of interference by intrinsic magnetization. In addition to the weak localization, we observe Altshuler-Aronov electron-electron interactions effect in this material.



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