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arXiv · 2009.12925

Dynamical spin susceptibility in La2CuO4 studied by resonant inelastic x-ray scattering

H. C. Robarts·M. Garcia-Fernandez·J. Li·A. Nag·A. C. Walters·N. E. Headings·S. M. Hayden·Ke-Jin Zhou
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Abstract

Resonant inelastic X-ray scattering (RIXS) is a powerful probe of elementary excitations in solids. It is now widely applied to study magnetic excitations. However, its complex cross-section means that RIXS has been more difficult to interpret than inelastic neutron scattering (INS). Here we report high-resolution RIXS measurements of magnetic excitations of La2CuO4, the antiferromagnetic parent of one system of high-temperature superconductors. At high energies (~2 eV), the RIXS spectra show angular-dependent dd orbital excitations which are found to be in good agreement with single-site multiplet calculations. At lower energies (<0.3 eV), we show that the wavevector-dependent RIXS intensities are proportional to the product of the single-ion spin-flip cross section and the dynamical susceptibility of the spin-wave excitations. When the spin-flip crosssection is dividing out, the RIXS magnon intensities show a remarkable resemblance to INS data. Our results show that RIXS is a quantitative probe the dynamical spin susceptibility in cuprate and therefore should be used for quantitative investigation of other correlated electron materials.

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H. C. Robarts, M. Garcia-Fernandez, J. Li, A. Nag, A. C. Walters, N. E. Headings, S. M. Hayden, Ke-Jin Zhou. 2020-09-27. Dynamical spin susceptibility in La2CuO4 studied by resonant inelastic x-ray scattering. https://doi.org/10.1103/physrevb.103.224427

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