title: Magnetic-field-induced ferroelectric polarization reversal in magnetoelectric composites revealed by piezoresponse force microscopy.
abstract: Controlling electric polarization (or magnetization) in multiferroic materials with external magnetic fields (or electric fields) is very important for fundamental physics and spintronic devices. Although there has been some progress on magnetic-field-induced polarization reversal in single-phase multiferroics, such behavior has so far never been realized in composites. Here we show that it is possible to reverse ferroelectric polarization using magnetic fields in a bilayer Terfenol-D/PMN-33%PT composite. We realized this by ferroelectric domain imaging using piezoresponse force microscopy (PFM) under applied magnetic field loading. The internal electric field caused by the magnetoelectric (ME) effect in the PMN-PT crystal is considered as the driving force for the 180° polarization switching, and its existence is verified by switching spectroscopy PFM testing under a series of external magnetic fields. A quantitative method is further suggested to estimate the local ME coefficient based on the switching spectroscopy PFM testing results.
authors: LTCS and Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, 100871, China. lifaxin@pku.edu.cn.
authors: Hongchen
authors: H
authors: Miao
authors: Xilong
authors: X
authors: Zhou
authors: Shuxiang
authors: S
authors: Dong
authors: Haosu
authors: H
authors: Luo
authors: Faxin
authors: F
authors: Li