Observation of Two Nondispersive Magnetic Excitations in NiO by Resonant Inelastic Soft-X-Ray Scattering

Abstract

We present high resolution (DeltaE=120 meV) resonant inelastic x-ray scattering data measured at the Ni L3 edge (2p_{3/2}-->3d) on the paradigmatic antiferromagnetic oxide NiO. Spectra reveal clear signatures of magnetic excitations at approximately 95 and approximately 190 meV whose energy seems independent from transferred momentum. These spectral features are well reproduced by a single Ni2+ ion model in an effective exchange field. Within this local model the two magnetic excitations are characterized by a variation of the atomic magnetic moment along the local ordering direction (DeltaS_{alpha}) of one and two units. The DeltaS_{alpha}=2 case has different nature from bimagnons observed in optical Raman spectra, for which DeltaS_{alpha}=0.

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

“…Therefore the spin selection rule does not apply, giving rise to a large spectral weight of such high-spin to low-spin excitations. 65,66 This is corroborated by the absence of RIXS peaks between 1.1 and 1.3 eV in the data obtained at the O K edge (see Fig. 1).…”

Observation ofddexcitations in NiO andNiCl2usingKVeenendaal1, Liu2, Carpenter3 et al. 2011Phys. Rev. B293190View full textAdd to dashboardCite

“…One subsequently detects the energy ω ′ of the X-rays resulting from the radiative decay of the core hole. Local dd transitions 1 , spin-flips 2 , and singlemagnon excitations 3 have been observed in the soft X-ray region at the transition-metal L-and M -edges. However, low-energy X-rays do not have sufficient penetration depth to study, for example, the electronic structure in technologically-relevant materials, such as transitionmetal molecular compounds in solution.…”

Unraveling Orbital Correlations with Magnetic Resonant Inelastic X-Ray Scattering

“…Recently, resonant inelastic x-ray scattering (RIXS) [19][20][21][22] has been proven successful in measuring spin excitations in various cuprates [23][24][25][26][27][28], nickelates [29], and even iron-based compounds [30]. Here we show in a general setting how the polarization dependent intensity of magnetic RIXS directly provides an insight into the orbital correlations in the ground state of correlated materials.…”