EFFECT OF EPITAXIAL STRAIN ON THE STRUCTURAL AND FERROELECTRIC PROPERTIES OF Bi2FeCrO6THIN FILMS

Bi2FeCrO6thin films were epitaxially grown by pulsed laser deposition on (100)-oriented LaAlO3, (LaAlO3)0.3(Sr2LaTaO6)0.7and SrTiO3single crystalline substrates with and without epitaxial CaRuO3buffered layer. The in-plane compressive strain induces monoclinic distortion of the Bi2FeCrO6lattice cell. The strain originates from lattice mismatch between CaRuO3and single crystal substrates. The similar crystal structure of the substrate and the layer lead to coherent epitaxial growth of the heterostructures and avoid strain relaxation in particular for BFCO films deposited on LaAlO3substrates. The ferroelectric character is demonstrated for all grown BFCO films. The residual in-plane strain weakly affects the effective piezoelectric coefficient of BFCO layers.