Magnetic State Switching in FeGa Microstructures

This work demonstrates that magnetoelectric composite heterostructures can be designed at the length scale of 10 microns that can be switched from a magnetized state to a vortex state, effectively switching the magnetization off, using electric field induced strain. This was accomplished using thin film magnetoelectric heterostructures of Fe81.4Ga18.6 on a single crystal (011) [Pb(Mg1/3Nb2/3)O3]0.68-[PbTiO3]0.32 (PMN-32PT) ferroelectric substrate. The heterostructures were tripped from a multi-domain magnetized state to a flux closure vortex state using voltage induced strain in a piezoelectric substrate. FeGa heterostructures were deposited on a Si-substrate for SQUID magnetometry characterization of the magnetic properties. The magnetoelectric coupling of a FeGa continuous film on PMN-32PT was characterized using a MOKE magnetometer with bi-axial strain gauges, and magnetic multi-domain heterostructures were imaged using X-Ray Magnetic Circular Dichroism – Photoemission Electron Microscopy (XMCD-PEEM) during the transition to the vortex state. The domain structures were modelled using MuMax3, a micromagnetics code, and compared with observations. The results provide considerable insight into designing magnetoelectric heterostructures that can be switched from an “on” state to an “off” state using electric field induced strain.

Bi(Mg1/2Zr1/2)O3-PbZrO3-PbTiO3 relaxor ferroelectric ceramics with large and temperature-insensitive electric field induced strain response

Ferroelectric ceramic materials with large and temperature-insensitive strain response are highly desired for the practical application of actuator in harsh environment conditions. In this work, a novel xBi(Mg1/2Zr1/2)O3-(0.55-x)PbZrO3-0.45PbTiO3 (xBMZ-PZ-0.45PT) ternary...