Tunneling Anisotropic Magnetoresistance in L1_0-MnGa Based Antiferromagnetic Perpendicular Tunnel Junction

We report on the tunneling anisotropic magnetoresistance in antiferromagnetic perpendicular tunnel junction consisting of L1_0-MnGa/FeMn/AlO_x/Pt grown on GaAs (001) substrates by molecular-beam epitaxy. The temperature-dependent perpendicular exchange bias effect reveals an exchange coupling between ferromagnetic L1_0-MnGa and antiferromagnetic FeMn. The rotation of antiferromagnetic spins in FeMn can be driven by perpendicularly magnetized L1_0-MnGa due to the exchange-spring effect at the interface and leads to room-temperature tunneling anisotropic magnetoresistance ratio of 0.86%. We also find that the tunneling anisotropic magnetoresistance strongly depends on temperature and angle. These results have broadened the material selection range for high performance antiferromagnetic spintronic devices.