title: Local Magnetoelectric Effect in La-Doped BiFeO3 Multiferroic Thin Films Revealed by Magnetic-Field-Assisted Scanning Probe Microscopy.
abstract: Multiferroic La-doped BiFeO3 thin films have been prepared by a sol-gel plus spin-coating process, and the local magnetoelectric coupling effect has been investigated by the magnetic-field-assisted scanning probe microscopy connected with a ferroelectric analyzer. The local ferroelectric polarization response to external magnetic fields is observed and a so-called optimized magnetic field of ~40 Oe is obtained, at which the ferroelectric polarization reaches the maximum. Moreover, we carry out the magnetic-field-dependent surface conductivity measurements and illustrate the origin of local magnetoresistance in the La-doped BiFeO3 thin films, which is closely related to the local ferroelectric polarization response to external magnetic fields. This work not only provides a useful technique to characterize the local magnetoelectric coupling for a wide range of multiferroic materials but also is significant for deeply understanding the local multiferroic behaviors in the BiFeO3-based systems.
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China.
authors.forename: Dan-Feng
authors.initials: DF
authors.lastname: Pan
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China.
authors.forename: Ming-Xiu
authors.initials: MX
authors.lastname: Zhou
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China.
authors.forename: Zeng-Xing
authors.initials: ZX
authors.lastname: Lu
authors.affiliation: Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky, 40506-0055, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China.|Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
authors.forename: Jun-Ming
authors.initials: JM
authors.lastname: Liu
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China.|Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
authors.forename: Guang-Hou
authors.initials: GH
authors.lastname: Wang
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, China. wanjg@nju.edu.cn.|Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China. wanjg@nju.edu.cn.
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Wan
keywords: La-doped BiFeO3 thin film; Local conductivity; Magnetoelectric coupling; Multiferroicity; Scanning probe microscopy