The effects of oxygen pressure on the structural, magnetic, and ferroelectric properties of 0.55BiFe0.95Ga0.03Mn0.02O3–0.45BaTiO3 thin films.

• The BFGMO–BTO film is successfully prepared by pulsed laser deposition method. • The structure and magnetic properties highly depend on the oxygen pressure. • The electric field used to switch ferroelectric domains increases with the film thickness. • The work contributes to finding a route to achieve more excellent room-temperature multiferroic films. 0.55BiFe 0.95 Ga 0.03 Mn 0.02 O 3 –0.45BaTiO 3 (BFGMO–BTO) thin films have been epitaxially grown on (0 0 1)-oriented Nb-doped SrTiO 3 (NSTO) single-crystal substrates by the pulsed laser deposition. X-ray diffraction, selected area electron diffraction, magnetic hysteresis loop, and piezoresponse force microscopy results show that the structural and magnetic properties of the BFGMO–BTO epitaxial films can be progressively tuned by the oxygen pressure (P O 2 ) during film deposition. The films prepared at P O 2 = 5 Pa phase separated into BFGMO and BTO phases, however, with increasing P O 2 to 20 Pa the films evolve from two phases to single phase with the best crystalline quality, largest saturation magnetization, lowest coercive field and relatively easy-switchable ferroelectric domains. [ABSTRACT FROM AUTHOR]