Metal-insulator transition in low dimensional La0.75Sr0.25VO3 thin films

We report on the metal-insulator transition that occurs as a function of film thickness in ultrathin La0.75Sr0.25VO3 films. The metal-insulator transition displays a critical thickness of 5 unit cell. Above the critical thickness, metallic films exhibit a temperature driven metal-insulator transition with weak localization behavior. With decreasing film thickness, oxygen octahedron rotation in the films increases, causing enhanced electron-electron correlation. The electron-electron correlations in ultrathin films induce the transition from metal to insulator in addition to Anderson localization.