Metal-insulator transition in LaVO₃ thin films

Using Molecular Beam Epitaxy (MBE), we grew thin films of LaVO₃ under a partial pressure of oxygen and ozone of ~1∙10^-7 torr and a substrate temperature of ~650° C. To probe the electrical properties of the material, we applied a bipolar current across the samples over a range of temperatures, taking the average of the voltages produced by currents in either direction to determine the resistivity. The samples showed metallic transport down to near 120 K, with the resistivity decreasing by a factor of 20 compared to that at 300 K. Below 120 K, a drastic change in the electronic properties of the samples appears, suggestive of a transition to a gapped state.