Onset of two-dimensional (2D) ferromagnetic (FM) short-range order with T2D≃150 K above A-type antiferromagnetic (AF) Néel temperature TN = 139 K was observed in 100 G low field for orbital-ordered LaMnO3. The A-type AF long-range order is stabilized through strong 2D basal plane FM superexchange coupling of orbital-ordered eg electrons and weak c-axis AF coupling. Both T2D and TN are field dependent, and merge in 1 T high field around 130 K. Mn K-edge X-ray absorption near-edge spectrum for orbital-ordered LaMnO 3 at room temperature indicates a pre-edge splitting of 2.0 eV due to weakly allowed 1s-3d dipole transition.
- 2D FM short range fluctuation
- A-type AF order
- Orbital order
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering