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arXiv · 1101.2356

The Spin-Exchange Dynamical Structure Factor of the S=1/2 Heisenberg Chain

Antoine Klauser·Jorn Mossel·Jean-Sebastien Caux·Jeroen van den Brink
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Abstract

We determine the spin-exchange dynamical structure factor of the Heisenberg spin chain, as is measured by indirect Resonant Inelastic X-ray Scattering (RIXS). We find that two-spin RIXS excitations nearly entirely fractionalize into *two spinon* states. These share the same continuum lower bound as single-spin neutron scattering excitations, even if the relevant final states belong to orthogonal symmetry sectors. The RIXS spectral weight is mainly carried by higher-energy excitations, and is beyond the reach of the low-energy effective theories of Luttinger liquid type.

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Antoine Klauser, Jorn Mossel, Jean-Sebastien Caux, Jeroen van den Brink. 2011-01-12. The Spin-Exchange Dynamical Structure Factor of the S=1/2 Heisenberg Chain. https://doi.org/10.1103/physrevlett.106.157205

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