Magnetic ordering and dielectric relaxation in the double perovskite YBaCuFeO5. (1st March 2017)

• Record Type: Journal Article
• Authors: Lai, Yen-Chung; Du, Chao-Hung; Lai, Chun-Hao; Liang, Yu-Hui; Wang, Chin-Wei; Rule, Kirrily C; Wu, Hung-Cheng; Yang, Hung-Duen; Chen, Wei-Tin; Shu, G J; Chou, F-C
• Is Part Of: Journal of physics. Volume 29:Number 14(2017)
• Publication Date: 2017-03-01
• Subjects: multiferroics -- magnetic phase transition -- ferroelectric relaxation; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa5708
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Using magnetization, dielectric constant, and neutron diffraction measurements on a high quality single crystal of YBaCuFeO5 (YBCFO), we demonstrate that the crystal shows two antiferromagnetic transitions at T N 1 ∼ 475 K and T N 2 ∼ 175 K, and displays a giant dielectric constant with a characteristic of the dielectric relaxation at T N 2 . It does not show the evidence of the electric polarization for the crystal used for this study. The transition at T N 1 corresponds with a paramagnetic to antiferromagnetic transition with a magnetic propagation vector doubling the unit cell along three crystallographic axes. Upon cooling, at T N 2, the commensurate spin ordering transforms to a spiral magnetic structure with a propagation vector of ( h 2 k 2 l 2 ± δ ), where h, k, and l are odd, and the incommensurability δ is temperature dependent. Around the transition boundary at T N 2, both commensurate and incommensurate spin ordering coexist.