Neutron powder-diffraction study of phase transitions in strontium-doped bismuth ferrite: 1. Variation with chemical composition. (23rd June 2022)

• Record Type: Journal Article
• Authors: Ma, Zhengzheng; Tan, Lei; Huang, Haijun; He, Lunhua; Chen, Jie; Lu, Huaile; Deng, Sihao; Yin, Wen; Zhang, Junrong; Tian, Haolai; Du, Rong; Arnold, Donna C; Phillips, Anthony E; Dove, Martin T
• Is Part Of: Journal of physics. Volume 34:Number 25(2022)
• Publication Date: 2022-06-23
• Subjects: magnetoelectric coupling -- doping -- bismuth ferrite -- neutron diffraction; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac6389
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We report results from a study of the crystal and magnetic structures of strontium-doped BiFeO3 using neutron powder diffraction and the Rietveld method. Measurements were obtained over a wide range of temperatures from 300–800 K for compositions between 10%–16% replacement of bismuth by strontium. The results show a clear variation of the two main structural deformations—symmetry-breaking rotations of the FeO6 octahedra and polar ionic displacements that give ferroelectricity—with chemical composition, but relatively little variation with temperature. On the other hand, the antiferromagnetic order shows a variation with temperature and a second-order phase transition consistent with the classical Heisenberg model. There is, however, very little variation in the behaviour of the antiferromagnetism with chemical composition, and hence with the degree of the structural symmetry-breaking distortions. We therefore conclude that there is no significant coupling between antiferromagnetism and ferroelectricity in Sr-doped BiFeO3 and, by extension, in pure BiFeO3 .