On the structural origin of the single-ion magnetic anisotropy in LuFeO sub(3)

• Published in: Journal of physics. Condensed matter 2016-04, Vol.28 (15), p.156001-156010
• Main Authors: Cao, Shi, Zhang, Xiaozhe, Paudel, Tula R, Sinha, Kishan, Wang, Xiao, Jiang, Xuanyuan, Wang, Wenbin, Brutsche, Stuart, Wang, Jian, Ryan, Philip J, Kim, Jong-Woo, Cheng, Xuemei, Tsymbal, Evgeny Y, Dowben, Peter A, Xu, Xiaoshan
• Format: Article
• Language: English
• Subjects: Anisotropy; Condensed matter; Conduction band; Electronic structure; Minorities; Spectra; Splitting; Three dimensional
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/28/15/156001

The electronic structure for the conduction bands of both hexagonal and orthorhombic LuFeO sub(3) thin films have been measured using x-ray absorption spectroscopy at oxygen K (O K) edge. Dramatic differences in both the spectral features and the linear dichroism are observed. These differences in the spectra can be explained using the differences in crystal field splitting of the metal (Fe and Lu) electronic states and the differences in O 2p-Fe 3d and O 2p-Lu 5d hybridizations. While the oxidation states have not changed, the spectra are sensitive to the changes in the local environments of the Fe super(3+) and Lu super(3+) sites in the hexagonal and orthorhombic structures. Using the crystal-field splitting and the hybridizations that are extracted from the measured electronic structures and the structural distortion information, we derived the occupancies of the spin minority states in Fe super(3+), which are non-zero and uneven. The single ion anisotropy on Fe super(3+) sites is found to originate from these uneven occupancies of the spin minority states via spin-orbit coupling in LuFeO sub(3).