Electrical Side-Gate Control of Magnetic Anisotropy in a Composite Multiferroic

Controlling magnetism via applied voltage rather than a magnetic field allows for smaller and energy-efficient electronic devices – which is a drive for studying magnetoelectric coupling in multiferroics. Composite multiferroics allow for choosing desired qualities in the coupled ferroic materials, allowing for above room temperature function and improved coupling compared to single-phase multiferroic materials. Thus, this work studies the coupling between epitaxial low damping ferromagnet on relaxor ferroelectric in a multiferroic heterostructure. Using a side-gate geometry, allowing for large electric field application with small applied voltages, we investigate the electrical control of magnetoresistance and magnetic anisotropy of single-crystalline MBE-grown Fe_0.75Co_0.25 on PMN-PT(001). Angle-dependent magnetoresistance scans reveal that the origin of this effect is strain-mediated magnetoelectric coupling, and Brillouin light scattering is used to investigate the change in magnetic dynamics. This electrical control of magnetic properties could serve as a building block for future magnetoelectronic and magnonic devices.