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arXiv · 0707.2416

Weak localization in GaMnAs: evidence of impurity band transport

L. P. Rokhinson·Y. Lyanda-Geller·Z. Ge·S. Shen·X. Liu·M. Dobrowolska·J. K. Furdyna
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Abstract

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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L. P. Rokhinson, Y. Lyanda-Geller, Z. Ge, S. Shen, X. Liu, M. Dobrowolska, J. K. Furdyna. 2007-07-17. Weak localization in GaMnAs: evidence of impurity band transport. https://doi.org/10.1103/physrevb.76.161201

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