  High-quality epitaxial SrVO3 (SVO) thin films of various thicknesses were
grown on (001)-oriented LSAT substrates by pulsed electron-beam deposition
technique. Thick SVO films (~25 nm) exhibited metallic behavior with the
electrical resistivity following the T2 law corresponding to a Fermi liquid
system. We observed a temperature driven metal-insulator transition (MIT) in
SVO ultrathin films with thicknesses below 6.5 nm, the transition temperature
TMIT was found to be at 50 K for the 6.5 nm film, 120 K for the 5.7 nm film and
205 K for the 3 nm film. The emergence of the observed MIT can be attributed to
the dimensional crossover from a three-dimensional metal to a two-dimensional
Mott insulator, as the resulting reduction in the effective bandwidth W opens a
band gap at the Fermi level. The magneto-transport study of the SVO ultrathin
films also confirmed the observed MIT is due to the electron-electron
interactions other than localization.
