Strain effects on the metal-insulator transition
in V2O3 thin films
| The effect of epitaxial stress on the metal-insulator transition of V2O3 has been studied in the form of epitaxial thin films grown on α-Al2O3 (0001) and LiTaO3 (0001) substrates. A metallic phase is stabilized down to 2 K in the V2O3 thin film on α-Al2O3 (0001), where the a axis is compressed by 4 % owing to large epitaxial stress. On the other hand, the transition temperature TMI is raised by 20 K from the value of 170 K in bulk sample in the film on LiTaO3 (0001), where the a axis is expanded. These results suggest an intimate relationship between the a-axis length and TMI in V2O3. The conductivity of the metallic ultrathin films shows logarithmic temperature dependence below 20 K, probably due to Anderson localization in two-dimensional systems. |