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arXiv · 0706.0109

Spin-Polarized Tunneling as a probe of (Ga,Mn)As electronic properties

M. Elsen·H. Jaffres·R. Mattana·L. Thevenard·A. Lemaitre·J. -M. George
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Abstract

We present magnetic and tunnel transport properties of (Ga,Mn)As/(In,Ga)As/(Ga,Mn)As structure before and after adequate annealing procedure. The conjugate increase of magnetization and tunnel magnetoresistance obtained after annealing is shown to be associated to the increase of both exchange energy $Δ$$_{exch}$ and hole concentration by reduction of the Mn interstitial atom in the top magnetic electrode. Through a 6x6 band k.p model, we established general phase diagrams of tunneling magnetoresistance (TMR) and tunneling anisotropic magnetoresistance (TAMR) \textit{vs.} (Ga,Mn)As Fermi energy (E$_F$) and spin-splitting parameter (B$_G$). This allows to give a rough estimation of the exchange energy $Δ$$_{exch}$=6B$_G$$\simeq$120 meV and hole concentration p$\simeq1.10^{20}$cm$^{-3}$ of (Ga,Mn)As and beyond gives the general trend of TMR and TAMR \textit{vs.} the selected hole band involved in the tunneling transport.

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M. Elsen, H. Jaffres, R. Mattana, L. Thevenard, A. Lemaitre, J. -M. George. 2007-06-01. Spin-Polarized Tunneling as a probe of (Ga,Mn)As electronic properties. https://arxiv.org/abs/0706.0109

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