Multi-Ferroic Properties on BiFeO3/BaTiO3 Multi-Layer Thin-Film Structures with the Strong Magneto-Electric Effect for the Application of Magneto-Electric Devices

Abstract

The characteristics of X-ray Diffraction (XRD), Current (I)-Voltage (V), and the Polarization-Electric field (P-E) on the BiFeO3 (BFO), BaTiO3 (BTO), and our proposed Multi-Layer (ML) BiFeO3/BaTiO3 (BFO/BTO) samples are studied systemically. The influence of these films with and without different external Magnetic (Mex.) inputs is also investigated. Our proposed multi-ferroic ML BFO/BTO sample has a lower tunneling current (Jg) (~5 × 103 times) and a stronger magneto-electric effect (an ~25 times higher value of the change of saturated polarization Ps with the Mex. inputs than the pure multi-ferroic BFO sample. The material properties for ML BFO/BTO samples can be optimized with the combination of the advantages of BFO and BTO thin films. The stronger magneto-electric effect in our proposed ML samples can have many applications such as magnetic sensors, magnetic electric devices, and logic Magneto-Electric Spin–Orbit (MESO) devices.

Electrical, magnetic and microwave absorption properties of multiferroic NiFe2O4-BaTiO3 nanocomposites

“…We see that the hysteresis P(E) curve has a narrow nature and curvature when examined in the electric field generated by the applied external voltages of 100-900 V. Nevertheless, the observed P(E) loops do not show the saturation status yet, which could be related to the leakage currents in the sample. This behavior is also agreed with previous studies on BTO family [26,47,[50][51][52]58]. With an increase in NFO content, the hysteresis curves tend to expand gradually in the shape of a fingerprint.…”

“…The positive and negative counterpart values of E C and P r are not asymmetry, corresponding to the presence of an internal electric field, which is caused by the short distance, off-center and as well as the inherent movement of bound electrons [72]. Regarding the studies of multiferroic BTO-based composites with other FM phases fabricated by using mechano-chemical activation technique [71], high energy ball milling [50] and solid-state reaction methods [39,51,52,73] have shown similar results. To improve the electrical and magnetic properties of multiferroics, besides changing the fraction of the FM and FE phases, the fabricated methods also greatly affect their characters, as shown in table 1.…”

“…Additionally, the hysteresis curves tend to expand, the E C value gradually increases from 0.4 to 2.0 kV cm −1 , the P r value increases gradually from 0.004 to 0.038 μC cm −2 for C0-C4. These increases are attributed to the pinning effect arising that relate to the presence of FM phase in composites [50][51][52]. The high internal polarization led to the enhancement of P r and P m [70].…”

“…Additionally, BTO is also a lead-free ferroelectric material with wide bandgap and quite high Curie temperature [40][41][42][43][44][45]. Therefore, BTO was chosen as a typical FE material to create multiferroic composites, such as BaTiO 3 -NiFe 2 O 4 [26], BaTiO 3 -CoFe 2 O 4 [41], BaTiO 3 -Ni 0.7 Zn 0.3 Fe 2 O 4 [46], Ba 0.9 Sr 0.1 Ti 0.9 Zr 0.1 O 3 -CoFe 2 O 4 [47], Ba 0.85 Ca 0.15 Ti 0.9 Zr 0.1 O 3 -CoFe 2 O 4 [48], BaTiO 3 -CoFe 2 O 4 [49], BaTiO 3 -BiFeO 3 [50], BaTiO 3 -Bi 0.85 La 0.15 FeO 3 [51], [0.5(Ba 0.7 Ca 0.3 TiO 3 )−0.5(BaZr 0.2 Ti 0.8 O 3 )]-Co 0.9 NiFe 2 O 4 [52]. Among spinel ferrites, nickel ferrite (NiFe 2 O 4 : NFO) is a typical ferromagnetic exhibiting the high initial permeability, which is an important character to improve the electromagnetic conversion factor in multiferroic composites [26,27,29].…”

Chemical Solution Deposition of La-Substituted BiFe0.5Sc0.5O3 Perovskite Thin Films on Different Substrates

“…Moreover, the aspects such as preferred orientation or surface strain can be considered as an additional powerful tool, allowing the physical properties of the materials to be tuned [18,19]. For the fabrication of multicomponent oxide thin films, various deposition approaches, including vacuum-based and non-vacuum based techniques, can be successfully employed [20][21][22][23][24]. It is well known that for some advanced deposition methods, such as metal organic chemical solution deposition, the precise stoichiometric control in multicomponent systems is a very challenging task because of different volatility of precursors, different deposition rates, etc.…”