Self-Poling-Induced Magnetoelectric Effect in Highly Strained Epitaxial BiFeO3/La0.67Sr0.33MnO3-δ Multiferroic Heterostructures

Dong Li; Dongxing Zheng; Junlu Gong; Wanchao Zheng; Chao Jin; Haili Bai

doi:10.1021/acsami.7b05803

Self-Poling-Induced Magnetoelectric Effect in Highly Strained Epitaxial BiFeO₃/La_0.67Sr_0.33MnO_3-δ Multiferroic Heterostructures

ACS Appl Mater Interfaces. 2017 Jul 19;9(28):24331-24338. doi: 10.1021/acsami.7b05803. Epub 2017 Jul 10.

Authors

Dong Li¹, Dongxing Zheng¹, Junlu Gong¹, Wanchao Zheng¹, Chao Jin¹, Haili Bai¹

Affiliation

¹ Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Institute of Advanced Materials Physics, Faculty of Science, Tianjin University , Tianjin 300350, P. R. China.

PMID: 28649827
DOI: 10.1021/acsami.7b05803

Abstract

Highly strained epitaxial BiFeO₃/La_0.67Sr_0.33MnO_3-δ (BFO/LSMO) heterostructures were fabricated on LaAlO₃ substrates by magnetron sputtering. The as-grown downward self-polarization of BFO capping layers was confirmed by piezoelectric force microscopy. Using the electrostatic field-induced charge screening, a hole depletion state was induced in ultrathin (8 nm) LSMO films. As a result of the interfacial charge coupling, appreciable saturated magnetization (M_S) increase of about 500 and 100% can be observed in LSMO with BFO capping at 5 and 300 K, respectively. Besides, LSMO phase translations can be revealed by the BFO thickness-related exchange bias field (H_E) and M_S of the BFO/LSMO heterostructures. The results established a new approach in achieving interfacial magnetoelectric couplings with thin self-polarized multiferroic layers.

Keywords: bismuth ferrite; magnetoelectric coupling effect; multiferroic heterostructures; phase transitions; polarization.