Thickness-dependence of the electronic properties in V2O3 thin films

TL;DR

This study investigates how the thickness of V2O3 thin films influences their lattice strain and electronic properties, revealing metallic behavior without a metal-insulator transition and strong electronic correlations.

Contribution

It provides detailed analysis of the thickness-dependent lattice strain and electronic properties of high-quality V2O3 thin films grown by pulsed laser deposition, highlighting their correlated metallic behavior.

Findings

V2O3 films are metallic between 2-300 K without a metal-insulator transition.

Resistivity follows a Fermi liquid T^2 dependence with A ≈ 0.14 μΩcmK^{-2}.

Hall resistance shows strong temperature dependence indicating electronic correlations.

Abstract

High quality vanadium sesquioxide V2O3 films (170-1100 {\AA}) were grown using the pulsed laser deposition technique on (0001)-oriented sapphire substrates, and the effects of film thickness on the lattice strain and electronic properties were examined. X-ray diffraction indicates that there is an in-plane compressive lattice parameter (a), close to -3.5% with respect to the substrate and an out-of-plane tensile lattice parameter (c) . The thin film samples display metallic character between 2-300 K, and no metal-to-insulator transition is observed. At low temperature, the V2O3 films behave as a strongly correlated metal, and the resistivity (\rho) follows the equation \rho =\rho_0 + A T^2, where A is the transport coefficient in a Fermi liquid. Typical values of A have been calculated to be 0.14 \mu\Omega cm K^{-2}, which is in agreement with the coefficient reported for V2O3 single crystals under high pressure. Moreover, a strong temperature-dependence of the Hall resistance confirms the electronic correlations of these V2O3 thin films samples.