Synthesis and electrical transport properties of the LaVO₃/SrTiO₃ interface

We have investigated the two dimensional electron gas at the interface of band gap insulator SrTiO₃ and mott insulator LaVO₃ in comparison to the well-known, purely band insulating LaAlO₃/SrTiO₃ system. Thin films of LaVO₃ were grown epitaxially on TiO₂ terminated SrTiO₃ single crystal substrates using RHEED-monitored pulsed laser deposition. Optimal process parameters for layer-by-layer growth were found resulting in the growth of atomically smooth films of well-defined thickness. Electrical transport measurements revealed an insulator-metal transition at a film thickness of six unit cells, which is different to previously reported values. Conducting samples showed metallic behavior in a wide temperature range, with their conductivity showing little to no dependence on layer thickness. This led to the conclusion of the metallic behavior being a merely interface driven effect.