title: Magnetic interactions in BiFe₀.₅Mn₀.₅O₃ films and BiFeO₃/BiMnO₃ superlattices.
abstract: The clear understanding of exchange interactions between magnetic ions in substituted BiFeO3 is the prerequisite for the comprehensive studies on magnetic properties. BiFe0.5Mn0.5O3 films and BiFeO3/BiMnO3 superlattices have been fabricated by pulsed laser deposition on (001) SrTiO3 substrates. Using piezoresponse force microscopy (PFM), the ferroelectricity at room temperature has been inferred from the observation of PFM hysteresis loops and electrical writing of ferroelectric domains for both samples. Spin glass behavior has been observed in both samples by temperature dependent magnetization curves and decay of thermo-remnant magnetization with time. The magnetic ordering has been studied by X-ray magnetic circular dichroism measurements, and Fe-O-Mn interaction has been confirmed to be antiferromagnetic (AF). The observed spin glass in BiFe0.5Mn0.5O3 films has been attributed to cluster spin glass due to Mn-rich ferromagnetic (FM) clusters in AF matrix, while spin glass in BiFeO3/BiMnO3 superlattices is due to competition between AF Fe-O-Fe, AF Fe-O-Mn and FM Mn-O-Mn interactions in the well ordered square lattice with two Fe ions in BiFeO3 layer and two Mn ions in BiMnO3 layer at interfaces.
authors.affiliation: 1] Department of Physics, Southeast University, Nanjing 211189, China [2] Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096, China [3] Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China [4] National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Sheng
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstrasse 400, D-01328 Dresden, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Khalid
authors.affiliation: Department of Materials Science and Engineering, Nanjing University, Nanjing 210008, China.
authors.forename: Yanqiang
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstrasse 400, D-01328 Dresden, Germany.
authors.forename: Yutian
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, Nanjing University, Nanjing 210008, China.
authors.forename: Xiangbiao
authors.initials: X
authors.lastname: Qiu
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Maocheng
authors.initials: M
authors.lastname: He
authors.affiliation: College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Shuangbao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstrasse 400, D-01328 Dresden, Germany.
authors.forename: Shengqiang
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Materials Science and Engineering, Nanjing University, Nanjing 210008, China.
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Zhai
authors.affiliation: York-Nanjing Joint Centre, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Liu
authors.affiliation: College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.affiliation: York-Nanjing Joint Centre, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Y B
authors.initials: YB
authors.lastname: Xu
authors.affiliation: 1] National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China [2] Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Du