Magnetoelectric coupling effect in lead-free Bi₄Ti₃O₁₂/CoFe₂O₄composite films derived from chemistry solution deposition

Abstract

Lead-free magnetoelectric composite films combining Bi 4 Ti 3 O 12 and CoFe 2 O 4 were synthesized by chemical solution deposition on Pt (100)/Ti/SiO 2 /Si substrate. Morphological and electrical domain structure, ferroelectric, leakage, dielectric, piezoelectric, magnetic and magnetoelectric properties were investigated for Bi 4 Ti 3 O 12 /CoFe 2 O 4 composite films. Well-defined interfaces between Bi 4 Ti 3 O 12 and CoFe 2 O 4 film layers and electrical domain structure were observed. The composite films show the coexistence of ferroelectric and ferromagnetic orders at room temperature. Larger piezoelectric coefficient and magnetization are obtained for the composite films, which is contributed to the magnetoelectric effect since it originates from the interface coupling through mechanical strain transfer. This work presents a feasible way to modulate the magnetoelectric coupling in ferromagnetic/ferroelectric composite films for developing lead-free micro-electro-mechanical system and information storage devices.

Strong magnetoelectric effect in pulse laser deposited [Ba(Zr0.2Ti0.8)O3‐0.5(Ba0.7Ca0.3)TiO3]/CoFe2O4 bilayer thin film

“…The larger values for α E, 31 may originate from the higher saturation magnetization as well as magnetostriction response of the CFO layer in the transverse direction. The α E values reported here are far better than the reported values of α E ; ~ 0.105 V/cm Oe for the CFO/BCTZO film, ~0.060 V/Oe cm for the PZT/CFO film, and ~0.029 V/cm Oe for the Bi 4 Ti 3 O 12 /CoFe 2 O 4 film . The fields at which α E ,31 and α E ,33 show a maximum correspond to the minimum seen in the M 2 ‐ H curve (in‐plane: 2 kOe, out of plane: 2.8 kOe), which is shown in the inset (i) of Figure B.…”

“…Further growth of the domains may hinder the piezoelectric deformation, leading to the drop in the value. 32 The larger values for α E, 31 34 The fields at which α E, 31 and α E, 33 show a maximum correspond to the minimum seen in the M 2 -H curve (in-plane: 2 kOe, out of plane: 2.8 kOe), which is shown in the inset (i) of Figure 4B. In a strain-mediated ME composite system, the coefficient α E follows the trend of a piezomagnetic coefficient (q ij ), that is, the dλ ij /dH vs H curve, since dλ ij /dH = q ij and λ ij is the magnetostrictive coefficient.…”

Advances in Magnetic Nanoparticles for Biomedical Applications

“…Besides their intrinsic nanoscale physical phenomena, their often exhibit exceptional optical, electrical, magnetic, and chemical properties, attracting vast attention in many biotechnological areas, such as magnetic resonance imaging, drug delivery systems, hyperthermia and labeling and separation of cells and proteins, among other biological entities . Different kinds of NPs, such as quantum dots, carbon nanotubes, gold NPs, silica NPs, polymeric NPs, and magnetic NPs (MNPs) have been designed and synthesized.…”

Magnetoelectric Functionality of Ni–Mn–In-Encapsulated AlN/Ni–Mn–In/Ni-Graded Heterostructure for Flexible Magnetic Field Sensor

“…The magnetoelectric coupling with different ferromagnetic materials such as terfenol-D, CoFe 2 O 4 , and Metglas has already been observed. ,,,,,, However, novel magnetostrictive materials are still required to be explored to enhance the multifunctionality of the ME heterostructure-based devices. The ferromagnetic shape memory alloys (FSMA, Ni–Mn–In) possess giant magnetostrictive strain than conventional ferromagnetic materials and can be promising for magnetoelectric devices. ,,, It undergoes first-order martensite transformation near room temperature, providing large strain during the austenite-to-martensite structural phase transition.…”