Orbital superexchange and crystal field simultaneously at play in YVO3: Resonant inelastic x-ray scattering at the VLedge and the OKedge

Abstract

Orbital superexchange and crystal field simultaneously at play in YVO3Benckiser, E.; Fels, L.; Ghiringhelli, G.; Sala, M. Moretti; Schmitt, T.; Schlappa, J.; Strocov, V. N.; Mufti, N.; Blake, G. R.; Nugroho, A. A. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. We report on the observation of orbital excitations in YVO 3 by means of resonant inelastic x-ray scattering (RIXS) at energies across the vanadium L 3 and oxygen K absorption edges. At the V L 3 edge, we are able to resolve the full spectrum of orbital excitations up to 5 eV. In order to unravel the effect of superexchange interactions and the crystal field on the orbital excitations, we analyzed the energy and temperature dependence of the intra-t 2g excitations at 0.1-0.2 eV in detail. While these results suggest a dominant influence of the crystal field, peak shifts of about 13-20 meV observed as a function of the transferred momentum q a reflect a finite dispersion of the orbital excitations. This is puzzling since theoretical models based on superexchange interactions predict a dispersion only for q c. Furthermore, we demonstrate that RIXS at the O K edge is very sensitive to intersite excitations. At the O K edge, we observe excitations across the Mott-Hubbard gap and an additional feature at 0.4 eV, which we attribute to two-orbiton scattering, i.e., an exchange of orbitals between adjacent sites. Altogether, our results indicate that both superexchange interactions and the crystal field are important for a quantitative understanding of the orbital excitations in YVO 3 .

Specific Heat on Single-crystalline YVO3

“…While the synchrotron X-ray detects an emerge of the forbidden reflection for Pbnm symmetry as lowering temperatures below T0, the infrared spectroscopy detects new modes from the infrared active. An evidence for the orbital ordering in YVO3 has recently been reported by means of the crystallographic studies [4] similar to those for the LaMnO3 [11] and resonance inelastic X-ray scattering study [12]. The change in the crystallographic structure at T0, as described earlier has provided evidence of the onset of the orbital ordering.…”

High-resolution resonant inelastic x-ray scattering study of the electron-phonon coupling in honeycomb α−Li2IrO3

“…Since these processes involve hopping via an intermediate oxygen atom, one may expect a greater sensitivity to them at the oxygen K-edge. Indeed, such behavior has already been demonstrated for YVO 3 [55].…”

Using RIXS to Uncover Elementary Charge and Spin Excitations

“…Besides cuprates, RIXS has also been utilized to measure excitations in iron-pnictide superconductors [45,46], felectron systems [47], and many other materials [48][49][50], including out of equilibrium [51]. Indeed, the idea of using polarization control to separate the spin-flip and non-spinflip excitations can be generalized to all kinds of materials.…”