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arXiv · 1110.3141

Analysis of Resonant Inelastic X-Ray Scattering in Stripe-Ordered Nickelate

Takuji Nomura·Eiji Kaneshita
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Abstract

We analyze theoretically the resonant inelastic x-ray scattering (RIXS) at the Ni K edge in the stripe-ordered state of La_{2-x}Sr_xNiO_4 at x=1/3. In the calculation of RIXS spectra, the stripe-ordered ground state is described within the Hartree-Fock approximation by using a realistic tight-binding model for Ni3dγand O2p_{x, y} orbitals, and the electron correlations in the electronic excitation processes are taken into account within the random-phase approximation. The calculated RIXS spectrum shows a tail toward the low-energy region when the momentum transfer of photons equals the stripe vector Q, being consistent with a recent experimental result. The origin of this anomalous momentum dependence of RIXS spectra is discussed microscopically.

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Takuji Nomura, Eiji Kaneshita. 2012-01-17. Analysis of Resonant Inelastic X-Ray Scattering in Stripe-Ordered Nickelate. https://doi.org/10.1143/jpsj.81.024707

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