Recent progress in nanostructured multiferroic Bi2FeCrO6 thin films

We report the latest progress on the growth and characterization of Bi2FeCrO6 (BFCO), a recently discovered multiferroic system. BFCO thin films and nanostructures exhibit exceptional multiferroic properties at room temperature. The growth of pure BFCO thin films on STO substrates is possible only in a narrow window of deposition parameters (i.e., Oxygen pressure pO2=1.2×10−2 mbar and around a substrate temperature TS=680 °C). The epitaxial growth stabilizes the metastable single phase of this material and promotes the Fe/Cr cation ordering in both thin films and nanostructures. This cationic ordering which is responsible for good magnetic properties of BFCO is also at the origin of pronounced photovoltaic (PV) properties observed in the epitaxial films grown on STO substrates. The results indicate that the ferroelectric polarization plays a dominant role in the observed PV effect.

(Top) Crystal structure of BFCO thin films deposited on (1 1 1)-oriented SrTiO3:Nb substrates and direct evidence of the presence of cationic ordering Fe/Cr in the films. (Bottom) Control of the crystal orientation and the shape of the epitaxial nanostructures by the orientation of the niobium-doped STO substrates.Figure optionsDownload as PowerPoint slideHighlights
► Growth optimization of Bi2FeCrO6 (BFCO) thin films and nanostructures by pulsed laser deposition.
► Ordered BFCO single phase have been stabilized by epitaxial strain.
► Arbitrary patterns of heteroepitaxial multiferroic BFCO nanostructures have been fabricated by PLD combined with nanostenciling.
► Experimental characterizations revealed the excellent multiferroic character of BFCO thin films and nanostructures.
► Unprecedentedly high power conversion efficiency for ferroelectrics was observed in 125 nm-thick highly ordered BFCO films. legend