Observation of strong magnetoelectric effects in Ba 0.7Sr 0.3TiO 3/La 0.7Sr 0.3MnO 3 thin film heterostructures

Abstract

A robust magnetoelectric (ME) response is essential in multiferroic thin films for potential nonvolatile ME memory elements. We report strong ME effects in bilayers and superlattices of Ba 0.7Sr 0.3TiO 3/La 0.7Sr 0.3MnO 3 composite multiferroics. The low-frequency ME coefficient ranges from 35 to 300 mV/cm Oe, depending on thickness, superlattice periodicity, and bias magnetic field and ac magnetic field orientations. Data on ME coupling are fitted well with a modified free-body model to obtain information on magneto-mechanical coupling in the composites. The strong ME coupling in spite of anticipated substrate clamping is a step forward towards the realization of multistate memories and read-write elements. © 2012 American Institute of Physics.