High-Pressure Tuning of Electrical Transport in Freestanding Oxide Films

Abstract: Electrical transport of oxide films under high pressure is largely unexplored due to the absence of a universal strategy. In this work, we have developed an in-house route to investigate the electrical transport properties of oxide films under high pressures, by improving the elasticity of freestanding oxide films and the robustness of high-pressure techniques on nano-devices. As a showcase, we investigated the electrical resistivity of perovskite SrIrO3 films under high pressures, and found a pressure-driven semimetal-to-insulator transition and an insulator-to-metal transition. At the monolayer-limit, the SrIrO3 films directly transform from an insulating state to a metallic state, highlighting the intriguing interplay of dimensionality and hydrostatic pressure in correlated oxides, which can be unveiled through the universal high-pressure strategy.