Impact of magnetization and hyperfine field distribution on high magnetoelectric coupling strength in BaTiO-BiFeO multilayers.

Correlations were established between the hyperfine field distribution around the Fe atoms, the multiferroic properties, and the high magnetoelectric coefficient in BaTiO-BiFeO multilayer stacks with variable BiFeO single layer thickness, down to 5 nm. Of key importance in this study was the deposition of Fe - enriched BiFeO, which enhances the sensitivity of conversion electron Mössbauer spectroscopy by orders of magnitude. The magnetoelectric coefficient α reaches a maximum of 60.

Simple synthesis and characterization of vertically aligned BaSrTiO-CoFeO multiferroic nanocomposites from CoFe nanopillar arrays.

A new strategy to elaborate (1-3) type multiferroic nanocomposites with controlled dimensions and vertical alignment is presented. The process involves a supported nanoporous alumina layer as a template for growth of free-standing and vertically aligned CoFe nanopillars using a room temperature pulsed electrodeposition process. BaSrTiO-CoFeO multiferroic nanocomposites were grown through direct deposition of BaSrTiO films by radio-frequency sputtering on the top surface of the pillar structure, with in situ simultaneous oxidation of CoFe nanopillars.

Correlation of Interface Impurities and Chemical Gradients with High Magnetoelectric Coupling Strength in Multiferroic BiFeO-BaTiO Superlattices.

The detailed understanding of magnetoelectric (ME) coupling in multiferroic oxide heterostructures is still a challenge. In particular, very little is known to date concerning the impact of the chemical interface structure and unwanted impurities that may be buried within short-period multiferroic BiFeO-BaTiO superlattices during growth. Here, we demonstrate how trace impurities and elemental concentration gradients contribute to high ME voltage coefficients in thin-film superlattices, which are built from 15 double layers of BiFeO-BaTiO.

Correlation of High Magnetoelectric Coupling with Oxygen Vacancy Superstructure in Epitaxial Multiferroic BaTiO₃-BiFeO₃ Composite Thin Films.

Epitaxial multiferroic BaTiO₃-BiFeO₃ composite thin films exhibit a correlation between the magnetoelectric (ME) voltage coefficient α and the oxygen partial pressure during growth. The ME coefficient α reaches high values up to 43 V/(cm·Oe) at 300 K and at 0.25 mbar oxygen growth pressure.

Sensitive in vivo cell detection using size-optimized superparamagnetic nanoparticles.

Magnetic nanoparticle (MNP) enabled cell visualization with magnetic resonance imaging (MRI) is currently an intensively studied area of research. In the present study, we have synthesized polyethylene glycolated (PEG) MNPs and validated their suitability as MR cell labeling agents in in vitro and in vivo experiments. The labeling of therapeutic potent mesenchymal stem cells (MSCs) with small core and large core MNPs was evaluated.