Anomalous pressure dependence of the electronic transport and anisotropy in SrIrO₃ films

Iridate oxides display exotic physical properties that arise from the interplay between a largespin–orbit coupling and electron correlations. Here, we present a comprehensive study of theeffects of hydrostatic pressure on the electronic transport properties of SrIrO3(SIO), a systemthat has recently attracted a lot of attention as potential correlated Dirac semimetal. Ourinvestigations on untwinned thin lms of SIO reveal that theelectrical resistivity of thismaterial is intrinsically anisotropic and controlled by the orthorhombic distortion of theperovskite unit cell. These effects provide another evidence for the strong coupling betweenthe electronic and lattice degrees of freedom in this class of compounds. Upon increasingpressure, a systematic increase of the transport anisotropies is observed. The anomalouspressure-induced changes of the resistivity cannot be accounted for by the pressuredependence of the density of the electron charge carriers, as inferred from Hall effectmeasurements. Moreover, pressure-induced rotations of the IrO6octahedra likely occur withinthe distorted perovskite unit cell and affect electron mobility of this system