High-pressure synthesis of orthorhombic SrIrO3 perovskite and its positive magnetoresistance

The orthorhombic SrIrO3 perovskite was synthesized under 5 GPa and 1000 degrees C. It is paramagnetic below about 170 K and transfers to an unknown magnetism under higher temperature. A band type metal to insulator transition caused by a pseudogap was observed at about 44 K. Interestingly a positive magnetoresistance, i.e., resistance increased with applying magnetic field, was observed in the orthorhombic SrIrO3 perovskite below about 170 K. (C) 2008 American Institute of Physics.