Room temperature Mott metal–insulator transition in V₂O₃ compounds induced via strain-engineering

Vanadium sesquioxide (V2O3) is an archetypal Mott insulator in which the atomic positions and electron correlations change as temperature, pressure, doping are varied, giving rise to different structural, magnetic, or electronic phase transitions. Remarkably, isostructural transition Cr-doped V2O3 between paramagnetic metallic insulating observed bulk has been elusive thin film compounds so far. Here, via continuous lattice deformations induced by heteroepitaxy, we demonstrate a room temperature metal–insulator 1.5% pure films. By means of controlled epitaxial strain, not only structure but also intrinsic optical properties films stabilized at intermediate states phases, inaccessible materials. This leads with unique features such colossal resistivity (ΔR/R up 100 000%) broad range constant values consequence strain-modulated bandgap. We propose new diagram for engineered in-plane tunable parameter. Our results that controlling transitions correlated systems strain offers radical approach create next generation devices.