本文研究了（Ga，Mn）As/（In，Ga）As/（Ga，Mn）As结构在适当退火前后的磁性和隧道输运性质。退火后得到的磁化强度和隧道磁电阻的共轭增加被证明是与交换能$Δ$ $_{exch}$和空穴浓度的增加，通过减少在顶部磁性电极中的Mn间隙原子。通过6 × 6能带k.p模型，建立了隧道磁电阻（TMR）和隧道各向异性磁电阻（TAMR）\textit{vs.}（Ga，Mn）As费米能级（E $_F$）和自旋分裂参数（B $_G$）的一般相图.这允许给出交换能量$Δ$ $_{exch}$ = 6 B $_G$ $\simeq$ 120毫电子伏和空穴浓度p $\simeq1.10^{20}$ cm $^{-3}$的（Ga，Mn）As和超越给出TMR和TAMR \textit{vs.}的一般趋势的一般估计所选择的空穴带参与隧穿传输。
英文摘要：
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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School of Materials Science and Engineering, Beihang University（北京航空航天大学材料科学与工程学院）；State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, Beihang University（热带海洋工程材料与材料评价国家重点实验室，北京航空航天大学）；The Analysis & Testing Center, Beihang University（北京航空航天大学分析测试中心）
