Impact of antiferromagnetism on the optical properties of rare earth nickelates

Abstract

We study the temperature dependence of the optical conductivity of rare-earth nickelate films of varying composition and strain close to the antiferromagnetic ordering temperature, TN. Two prominent peaks at 0.6 and 1.3 eV, which are characteristic of the insulating phase, display a small but significant increase in intensity when the material passes from para- to antiferromagnetic. This observation indicates the presence of a positive feedback between antiferromagnetic (AF) and bond disproportionation (BD) order. By analyzing the temperature dependence near TN, and using a Landau-type free-energy expression for BD and AF order, we infer that BD order is a necessary condition for the AF phase to appear, and that the antiferromagnetism contributes to stabilization of the bond disproportionation. This model also explains why hysteresis is particularly strong when the transition into the insulating state occurs simultaneously with antiferromagnetic order.

5 pages, 5 figures

References in corpus (5)

• Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
• Role of magnetic and orbital ordering at the metal-insulator transition in NdNiO3
• Low-energy description of the metal-insulator transition in the rare-earth nickelates
• Electronic Transitions in Strained SmNiO_3 Thin Films
• Tailoring the electronic transitions of NdNiO_3 films through (111)_pc oriented interfaces

Cited by in corpus (13)

• Temperature-independent thermal radiation
• Mechanism and Control Parameters of the Coupled Structural and Metal-Insulator Transition in Nickelates
• Generic optical excitations of correlated systems: $\pi$-tons
• RENiO3 single crystals (RE = Nd, Sm, Gd, Dy, Y, Ho, Er, Lu) grown from molten salts under 2000 bar oxygen-gas pressure
• Renormalization of effective interactions in a negative charge-transfer insulator
• Distortion mode anomalies in bulk PrNiO${}_3$ illustrating the potential of symmetry-adapted distortion mode analysis for the study of phase transitions
• Hybridization-switching induced Mott transition in ABO${}_3$ perovskites
• Anomalous electron transport in epitaxial NdNiO${}_3$ films
• Raman spectroscopic evidence for multiferroicity in rare earth nickelate single crystals
• Resonant inelastic x-ray scattering study of bond order and spin excitations in nickelate thin-film structures
• Charge disproportionation and site-selective local magnetic moments in the post-perovskite-type Fe${}_2$O${}_3$ under ultra-high pressures
• Probing photo-induced rearrangements in the NdNiO${}_3$ magnetic spiral with polarization-sensitive ultrafast resonant soft x-ray scattering
• Optical spectra of rare-earth nickelates