E-CONTROL · Electric-Field Control of Magnetic Domain Wall Motion and Fast Magnetic Switching: Magnetoelectrics at Micro, Nano, and Atomic Length Scales""

The aim of the proposed research is to study electric-field induced magnetic phenomena in thin-film ferromagnetic-ferroelectric heterostructures. In particular, the project addresses ferroic order competition and magnetoelectric coupling dynamics at micro, nano, and atomic length scales.The first part of the project focuses on the dynamics of coupled ferromagnetic-ferroelectric domains and electric-field induced magnetic domain wall motion at sub-nanosecond time scales. For simultaneous imaging of both ferroic domain responses to ultra-short electric-field pulses, the construction of a time-resolved polarization microscope is proposed. The second part relates to finite-size scaling of ferroic domain correlations in continuous films and electric-field control of magnetic effects in patterned nanostructures. Here, the aim is to elucidate the competition between magnetoelectric coupling at ferromagnetic-ferroelectric interfaces and the relevant energy scales within the bulk of ferroic materials. Moreover, electric-field induced domain wall motion in magnetic nanowires is pursued as a viable low-power alternative to current-driven spin-torque effects. Finally, the third part of E-CONTROL aims at visualization of magnetoelectric coupling effects with atomic precision. For this frontier study, the development of in situ transmission electron microscopy (TEM) techniques is proposed. The new measurement method enables the application of local electric fields on cross-sectional specimen during TEM analysis and this is bound to provide unique insights in strain-mediated and charge-modulated coupling mechanisms between ferromagnetic and ferroelectric thin films.""