Growth window and effect of substrate symmetry in hybrid molecular beam epitaxy of a Mott insulating rare earth titanate

Abstract

The conditions for the growth of stoichiometric GdTiO3 thin films by molecular beam epitaxy (MBE) are investigated. It is shown that relatively high growth temperatures (>750 °C) are required to obtain an MBE growth window in which only the stoichiometric film grows for a range of cation flux ratios. This growth window narrows with increasing film thickness. It is also shown that single-domain films are obtained by the growth on a symmetry-matched substrate. The influence of lattice mismatch strain on the electrical and magnetic characteristics of the GdTiO3 thin film is investigated.