Room-temperature multiferroic properties of sol-gel derived 0.5LaFeO3-Bi4Ti3O12 thin films with layered perovskite

• Published in: Journal of alloys and compounds 2017-06, Vol.709, p.729-734
• Main Authors: Zhang, D.J., Su, J., Lu, C.J., Zhang, Y.C., Zhang, C., Li, Y., Feng, L.Y.
• Format: Article
• Language: English
• Subjects: Dielectric relaxation; Ferroelectric materials; Ferromagnetism; Magnetic fields; Magneto-dielectric coefficient; Multiferroic; Multiferroic materials; Perovskite; Perovskite structure; Room temperature; Silicon dioxide; Silicon substrates; Sol-gel processes; Sol–gel; Temperature; Thin films
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.03.140

Random-oriented 0.5LaFeO3-Bi4Ti3O12 thin films were prepared via a sol–gel method on (111)Pt/Ti/SiO2/Si(100) substrates. According to X-ray diffraction analysis, the films have a single-phase Aurivillius perovskite structure with a space group Fmm2. As expected, the coexistence of ferroelectric and ferromagnetic properties was detected at room temperature. The remanent polarization (2Pr) and the saturated magnetization (Ms) are 61.94 μC/cm2 and ∼0.90 emu/cm3, respectively. Furthermore, a magneto-dielectric effect was demonstrated at room temperature with a magneto-dielectric coefficient of 0.67% under a low magnetic field of 0.25 T, probably resulting from the charge ordering of Fe2+ and Fe3+. Finally, a dielectric relaxation behavior was observed around 130 K, which is also related to the coexistence of Fe2+ and Fe3+. •The novel random-oriented 0.5LaFeO3-Bi4Ti3O12 thin films of layered Aurivillius structure were prepared.•The films reveal ferroelectric property, ferromagnetic property and the magneto-dielectric effect at room temperature.•The films are useful in multi-states memory for their better stability and less energy consumption.