Resonant inelastic x-ray scattering study of bond order and spin excitations in nickelate thin-film structures

Abstract

We used high-resolution resonant inelastic x-ray scattering (RIXS) at the Ni $L_3$ edge to simultaneously investigate high-energy interband transitions characteristic of Ni-O bond ordering and low-energy collective excitations of the Ni spins in the rare-earth nickelates $R$NiO${}_3$ ($R$ = Nd, Pr, La) with pseudocubic perovskite structure. With the support of calculations based on a double-cluster model we quantify bond order (BO) amplitudes for different thin films and heterostructures and discriminate short-range BO fluctuations from long-range static order. Moreover we investigate magnetic order and exchange interactions in spatially confined $R$NiO${}_3$ slabs by probing dispersive magnon excitations. While our study of superlattices (SLs) grown in the (001) direction of the perovskite structure reveals a robust non-collinear spin spiral magnetic order with dispersive magnon excitations that are essentially unperturbed by BO modulations and spatial confinement, we find magnons with flat dispersions and strongly reduced energies in SLs grown in the $(111{)}_{\text{pc}}$ direction that exhibit collinear magnetic order. These results give insight into the interplay of different collective ordering phenomena in a prototypical 3$d$ transition metal oxide and establish RIXS as a powerful tool to quantitatively study several order parameters and the corresponding collective excitations within one experiment.

13 pages, 8 figures, accepted in Physical Review B

References in corpus (13)

• Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
• Physics of ultrathin films and heterostructures of rare earth nickelates
• Ground state oxygen holes and the metal-insulator transition in the negative charge transfer rare-earth nickelates
• Bond disproportionation and dynamical charge fluctuations in the perovskite rare earth nickelates
• 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
• Bands, resonances, edge singularities and excitons in core level spectroscopy investigated within the dynamical mean field theory
• Tunable Charge and Spin Order in PrNiO${}_3$ Thin Films and Superlattices
• Tailoring the electronic transitions of NdNiO_3 films through (111)_pc oriented interfaces
• Complex magnetic order in nickelate slabs
• Interplay between breathing mode distortion and magnetic order in rare-earth nickelates $R$NiO${}_3$ within DFT+$U$
• Latent Instabilities in Metallic LaNiO3 Films by Strain Control of Fermi-Surface Topology
• Bond-Order and the Role of Ligand States in Stripe-Modulated IrTe2

Cited by in corpus (2)

• X-ray spectroscopy of rare-earth nickelate LuNiO${}_3$: LDA+DMFT study
• Control of the metal-insulator transition in NdNiO${}_3$ thin films through the interplay between structural and electronic properties