Effects of pillar size modulation on the magneto-structural coupling in self-assembled BiFeO₃–CoFe₂O₄ heteroepitaxy

Abstract

The magneto-structural coupling of BiFeO3 (BFO)–CoFe2O4 (CFO)/LaAlO3 (LAO) heteroepitaxy with various lateral sizes of CFO pillars embedded in a BFO matrix was investigated.

Formation and physical properties of the self-assembled BFO–CFO vertically aligned nanocomposite on a CFO-buffered two-dimensional flexible mica substrate

“…5(d) can be fitted with three main components: Fe 2+ 2p 3/2 (710.6 eV), Fe 3+ 2p 3/2 (713.1 eV) and Fe 2+ satellite peaks. 19,42 The ratio of Fe 3+ /Fe 2+ is estimated to be about 2.08. As for O 1s core level spectra ( Fig.…”

“…[14][15][16] The present work reports the detailed mechanisms leading to the self-assembled heteroepitaxial growth of the threedimensional (3D) BiFeO 3 -CoFe 2 O 4 (BFO-CFO) VAN on exible mica substrate. Previously, the BFO-CFO VAN grown on various rigid ceramic substrates has been illustrated as multiferroic nanocomposite exhibiting strong magnetoelectric coupling effects, [17][18][19][20] which can bring about profound application potential for next-generation electronic devices in elds such as memory, magnetic sensor, and energy harvesting. It has been recognized that the matrix-pillars conguration of the BFO-CFO VAN was enabled mainly via the surface energy difference between the interface of substrate/perovskite-structured BFO and substrate/spinel-structured CFO.…”

Magnetoelectricity in vertically aligned nanocomposites: Past, present, and future

“…51,52 Moreover, experiments have also been widely performed to improve the phase distribution morphologies and to enhance the properties of ME VANs. In addition to various piezoelectric and magnetostrictive phase combinations, 16,20,28,[32][33][34][35][36]53 studies (theory and experiments) reveal that the VAN morphology and properties can be controlled by shape and orientations, 3,20,25,54,55 deposition conditions, 19,[56][57][58][59] and substrate constraints. 24,[60][61][62][63]…”

“…68 It has been shown that both ME charge and voltage coefficients are significantly larger at large values of r, where the highest values are obtained at magnetic phase fractions of ~ 65% and ~ 93%, respectively. 68 Experimentally, the deposition conditions of epitaxial growth (e.g., target volume fraction, growth temperature, growth rate, and gas pressure for PLD) control the stoichiometry, 56,57 pillar shape, 58 pillar size, 59 and pillar distance. 69 The target volume fraction of perovskite and spinel phases directly determines the stoichiometry of VANs, which further affects their morphologies, and thus the magnetic anisotropy and ME properties.…”

“…19 The pillar size, on the other hand, affects the coupling behavior amongst the pillars, and the coupling behaviors between pillars and matrixes. 25,58,59,70…”