Tailoring large magnetoresistance in Dirac semimetal SrIrO3 films

Perovskite SrIrO3 is a special Dirac material with fascinating effects due to its strong electron correlation and spin–orbit coupling. In this work, a large magnetoresistance (MR) was observed not only in epitaxial SrIrO3 films but also in a SrIrO3/PbZr0.2Ti0.8O3 epitaxial heterostructure with a magnetic field applied perpendicular to the external electric field. The magnetoresistance of SrIrO3 (10 nm) and SrIrO3/PbZr0.2Ti0.8O3 (10 nm/30 nm) reach values as large as 40% and 110% at 9 T and 5 K, respectively. We believe that the unusual magnetoresistance is from the Dirac/Weyl state. Especially, the SrIrO3/PbZr0.2Ti0.8O3 bilayer shows negative magnetoresistance with strong oscillations close…