Ultrafast transient dynamics in composite multiferroics

Abstract

We investigate theoretically the dynamic multiferroic (MF) response of coupled ferroelectric (FE)/ferromagnetic (FM) composites upon excitation by a photo-induced acoustic strain pulse. Two magnetoelectric (ME) mechanisms are considered: interface strain- and charge-mediated ME couplings. The former results in demagnetization, depolarization and repolarization within tens of picoseconds via respectively magnetostriction and piezoelectricity. Charge ME interaction affects the FE/FM feedback response leading to magnetization recovery. Experimental realization based on time-resolved x-ray diffraction is suggested. The findings indicate the potential of composite MF for photo-steered, high-speed, multi-state electronic devices.