Influence of La doping in multiferroic properties of BiFeO3 thin films

Abstract

The influence of La doping on the crystal structure and multiferroic properties of BiFeO3 (BFO) thin films was investigated. BFO-based films of pure perovskite phase were deposited on BaPbO3∕Pt∕TiOx∕SiO2∕Si substrates by rf-magnetron sputtering. The increased dielectric constant and remanent polarization of the La-doped BFO films were due to the increased lattice parameters and an improved crystallinity. The polarization switching and the fatigue behavior of the BFO films were significantly enhanced by the La doping. The in-plane magnetization-field curves revealed that the room-temperature saturated magnetization of the BFO films increased with La doping.

Strain modulated transient photostriction in La and Nb codoped multiferroic BiFeO3 thin films

“…La and Nb codoped BFO film has been proved to show better ferroelectric properties in terms of large polarization and significantly reduced electrical leakage. 20,34 It is important to remind that the nonlinear susceptibility (v ð2Þ ) is a function of ferroelectric polarization. 22 Therefore, our finding suggests that the generation of acoustic phonons is strongly related to the optical rectification performance.…”

Periodicity dependence of the ferroelectric properties in BiFeO3∕SrTiO3 multiferroic superlattices

“…5,[7][8][9][10][11] Among the A site substitution, La doping was found to enhance the polarization and reduce the leakage behavior of BiFeO 3 thin films. 7 Substitution of cations like Sc 3+ , Nb 5+ , Cr 3+ , Mn 3+ in the B site, Sc 3+ and Nb 5+ were also found to improve the electrical properties. [8][9][10][11] The leakage current increases with the Ni 3+ -doping and decreases with the Ti 4+ -doping.…”

“…7 , 8 , 9 , 10 , 11 , 12 In epitaxially grown BiFeO 3 thin films, the leakage mechanism is dominated by Poole -Frenkel (P-F) emission with symmetric electrode configuration, while a mechanism close to (P-F) emission in an asymmetric electrode configuration 4 . Various efforts like i) substitution of heterovalent and homovalent substitutions on both A and B site cations which effectively controls the anion vacancies, 5,[7][8][9][10][11] ii) modification of the electrode material interface 12 and iii) recently a superlattice structure of a single periodicity of BiFeO 3 with SrTiO 3 13 were thusly employed to reduce the leakage behavior of BiFeO 3 thin films. Doping cations like, La, 3…”

Effects of nanostructuring and substrate symmetry on antiferromagnetic domain structure in LaFeO3thin films

“…The possibility to control magnetism in thin films and multilayers of perovskite oxides by epitaxial strain, [1][2][3] oxygen stoichiometry, 4-7 chemical substitution, 8,9 and substrate crystalline symmetry 10,11 has rendered such materials important model systems for fundamental studies of magnetic structure as well as attractive candidates for device applications. Advances in fabrication of complex oxide thin film nanostructures 12 and the recent development of novel tools for magnetic imaging with high spatial resolution have made the study of such systems on the nanometer length scale a realistic endeavor.…”