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X-ray edge singularity in integrable lattice models of correlated electrons

Fabian H. L. Essler·Holger Frahm
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Abstract

We study the singularities in X-ray absorption spectra of one-dimensional Hubbard and $t$--$J$ models. We use Boundary Conformal Field Theory and the Bethe Ansatz solutions of these models with both periodic and open boundary conditions to calculate the exponents describing the power-law decay near the edges of X-ray absorption spectra in the case where the core-hole potential has bound states.

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Fabian H. L. Essler, Holger Frahm. 1997-05-26. X-ray edge singularity in integrable lattice models of correlated electrons. https://doi.org/10.1103/physrevb.56.6631

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