Robust manipulation of magnetism in LaAO3/BaTiO3 (A = Fe, Mn and Cr) superstructures by ferroelectric polarization

IUCrJ

Chen, D.¹  Zhang, G.²  Cheng, Z.³ 

[1] Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475000, People's Republic of China;Institute for Superconducting and Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, Wollongong NSW 2500, Australia;School of Physics, Southeast University, Nanjing 211189, People's Republic of China

关键词: MULTIFERROIC LAYERS;    INTERFACES;    MAGNETISM;    METAL-INSULATOR TRANSITIONS;    FERROELECTRIC POLARISATION;    PEROVSKITE OXIDE SUPERSTRUCTURES;   

DOI  :  10.1107/S205225251801624X

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

Robust control of magnetism is both fundamentally and practically meaningful and highly desirable, although it remains a big challenge. In this work, perovskite oxide superstructures LaFeO3/BaTiO3 (LFO/BTO), LaMnO3/BaTiO3 (LMO/BTO) and LaCrO3/BaTiO3 (LCO/BTO) (001) are designed to facilitate tuning of magnetism by the electric field from ferroelectric polarization, and are systemically investigated via first-principles calculations. The results show that the magnetic ordering, conductivity and exchange interactions can be controlled simultaneously or individually by the reorientation of the ferroelectric polarization of BTO in these designed superstructures. Self-consistent calculations within the generalized gradient approximation plus on-site Coulomb correction did not produce distinct rotations of oxygen octahedra, but there were obvious changes in bond length between oxygen and the cations. These changes cause tilting of the oxygen octahedra and lead to spin, orbital and bond reconstruction at the interface, which is the structural basis responsible for the manipulation. With the G-type antiferromagnetic (G-AFM) ordering unchanged for both ±P cases, a metal–insulator transition can be observed in the LFO/BTO superstructure, which is controlled by the LFO thin film. The LMO/BTO system has A-type antiferromagnetic (A-AFM) ordering with metallic behavior in the +P case, while it shifts to a half-metallic ferromagnetic ordering when the direction of the polarization is switched. LCO/BTO exhibits C-type antiferromagnetic (C-AFM) and G-AFM orders in the +P and −P cases, respectively. The three purpose-designed superstructures with robust intrinsic magnetoelectric coupling are a particularly interesting model system that can provide guidance for the development of this field for future applications.

【 授权许可】

CC BY