Low voltage tunneling magnetoresistance in CuCrO₂-based semiconductor heterojunctions at room temperature

CuCrO₂-based heterojunction diodes with rectifying characteristics have been fabricated by combining p-type Mg-doped CuCrO₂ and n-type Al-doped ZnO. It was found that the current for the heterojunction in low bias voltage region is dominated by the trap-assisted tunneling mechanism. Positive magnetoresistance (MR) effect for the heterojunction can be observed at room temperature due to the tunneling-induced antiparallel spin polarization near the heterostructure interface. The MR effect becomes enhanced with the magnetic field, and shows the maximum at a bias voltage around 0.5V. The phenomena indicate that the CuCrO₂-based heterojunction is a promising candidate for low-power semiconductor spintronic devices.