A-type antiferromagnetic (AF) order with a two-dimensional (2D) ferromagnetic short-range fluctuation was observed in the stoichiometric orthorhombic La1−xEuxMnO3+δ system (0 < x < 1, δ 0 with trivalent Mn3+). The observation of strong basal plane ferromagnetic coupling of the A-type AF order with fluctuation above antiferromagnetic Néel temperature TN strongly indicates a C-type orbital ordering of eg electrons at higher temperature throughout the whole system. Anomalous decrease of TN from 139 K for LaMnO3, to 91 K for La0.5Eu0.5MnO3 and down to 42 K for EuMnO3 is the result of weaker anisotropic superexchange interaction due to stronger Jahn-Teller lattice distortion in orbital-ordered EuMnO3 from power x-ray Rietveld analysis and Mn K-edge x-ray absorption near-edge structure spectroscopic study.
|期刊||Physical Review B - Condensed Matter and Materials Physics|
|出版狀態||已發佈 - 2003 六月 19|
ASJC Scopus subject areas