We study tunneling anisotropic magnetoresistance in single-barrier tunnel junctions consisting of an $n$-type ferromagnetic semiconductor (In,Fe)Sb electrode, an (In,Al)Sb tunnel barrier, and an $n$-type InSb electrode. We measured the current-voltage ($I\text{−}V$) characteristics in the junctions and plotted the change in tunnel resistance $R$ or $\mathrm{d}I\text{/}\mathrm{d}V$ values when an external magnetic field $\mathit{H}$ was rotated between out-of-plane and in-plane directions with respect to the crystalline axes of the (In,Fe)Sb thin films. We observe a sizeable decrease in the junction resistance when $\mathit{H}$ is rotated from the perpendicular $\left[001\right]$ direction to the in-plane $\left[110\right]$ direction, whose origin is explained by considering $\mathit{H}$ direction dependent $s\text{−}d$ scatterings and the $s$,p-d hybridized band picture of (In,Fe)Sb. Meanwhile, when $\mathit{H}$ is rotated in the film plane, we observe a twofold anisotropic change in the $\mathrm{d}I\text{/}\mathrm{d}V$ with a maximum and a minimum when $\mathit{H}$ is along the $\left[\overline{1}10\right]$ and $\left[110\right]$ crystal axes, respectively. This result reflects in-plane twofold anisotropy in the density of states of the impurity band of (In,Fe)Sb, whose origin is attributed to a possible preferential distribution of Fe atoms along the $\left[\overline{1}10\right]$ direction.

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• Magnetism
• Spintronics
• Tunneling anisotropic magnetoresistance
• Dilute magnetic semiconductors
• Narrow band gap systems
• Tunnel junctions
• Molecular beam epitaxy