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Momentum dependent light scattering in insulating cuprates

F. H. Vernay·M. J. P. Gingras·T. P. Devereaux
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Abstract

We investigate the problem of inelastic x-ray scattering in the spin$-{1/2}$ Heisenberg model on the square lattice. We first derive a momentum dependent scattering operator for the $A_{1g}$ and $B_{1g}$ polarization geometries. On the basis of a spin-wave analysis, including magnon-magnon interactions and exact-diagonalizations, we determine the qualitative shape of the spectra. We argue that our results may be relevant to help interpret inelastic x-ray scattering experiments in the antiferromagnetic phase of the cuprates.

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F. H. Vernay, M. J. P. Gingras, T. P. Devereaux. 2007-01-12. Momentum dependent light scattering in insulating cuprates. https://doi.org/10.1103/physrevb.75.020403

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