Magnetic anisotropy modulation of magnetite in Fe3O4/BaTiO3(100) epitaxial structures

TL;DR

This study investigates how the magnetic anisotropy of magnetite films grown on BaTiO3(100) can be modulated through strain induced by the piezoelectric properties of BaTiO3, revealing potential for tunable magnetic devices.

Contribution

It demonstrates the strain-induced modulation of magnetic anisotropy in Fe3O4 films via the phase transitions of BaTiO3, highlighting a new approach for magnetic property control.

Findings

Discontinuities in magnetometry linked to BaTiO3 phase transitions.

Tensile strain in Fe3O4 at room temperature due to BaTiO3 lattice expansion.

Magnetic anisotropy variation correlates with magnetoelastic effects.

Abstract

Temperature dependent magnetometry and transport measurements on epitaxial Fe3O4 films grown on BaTiO3(100) single crystals by molecular beam epitaxy show a series of discontinuities, that are due to changes in the magnetic anisotropy induced by strain in the different crystal phases of BaTiO3. The magnetite film is under tensile strain at room temperature, which is ascribed to the lattice expansion of BaTiO3 at the cubic to tetragonal transition, indicating that the magnetite film is relaxed at the growth temperature. From the magnetization versus temperature curves, the variation in the magnetic anisotropy is determined and compared with the magnetoelastic anisotropies. These results demonstrate the possibility of using the piezoelectric response of BaTiO3 to modulate the magnetic anisotropy of magnetite films.