title: Magnetoelectricity coupled exchange bias in BaMnF4.
abstract: Multiferroic BaMnF4 powder was prepared by hydrothermal method. Hysteretic field dependent magnetization curve at 5 K confirms the weak ferromagnetism aroused from the canted antiferromagnetic spins by magnetoelectric coupling. The blocking temperature of 65 K for exchange bias coincides well with the peak at 65 K in the zero-field cooled temperature-dependent magnetization curve, which has been assigned to the onset temperature of two-dimensional antiferromagnetism. An upturn kink of exchange field and coercivity with decreasing temperature was observed from 40 K to 20 K, which is consistent with the two-dimensional to three-dimensional antiferromagnetic transition at Néel temperature (~26 K). In contrast to the conventional mechanism of magnetization pinned by interfacial exchange coupling in multiphases, the exchange bias in BaMnF4 is argued to be a bulk effect in single phase, due to the magnetization pinned by the polarization through magnetoelectric coupling.
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, &Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096, &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhou
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.|Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Wang
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.|College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Chang
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.|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: Jiangsu Laboratory of Advanced Functional Materials, Changshu Institute of Technology, Changshu 215500, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Qian
authors.affiliation: Jiangsu Laboratory of Advanced Functional Materials, Changshu Institute of Technology, Changshu 215500, China.
authors.forename: Zhida
authors.initials: Z
authors.lastname: Han
authors.affiliation: Department of Physics, Southeast University, Nanjing 211189, &Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096, &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.|National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Xu
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.|Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Du
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.|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: Department of Physics, Southeast University, Nanjing 211189, &Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096, &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Dong