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Correlation functions of the XXZ Heisenberg spin-1/2 chain in a magnetic field

N. Kitanine·J. M. Maillet·V. Terras
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Abstract

Using the algebraic Bethe ansatz method, and the solution of the quantum inverse scattering problem for local spins, we obtain multiple integral representations of the $n$-point correlation functions of the XXZ Heisenberg spin-$1 \over 2$ chain in a constant magnetic field. For zero magnetic field, this result agrees, in both the massless and massive (anti-ferromagnetic) regimes, with the one obtained from the q-deformed KZ equations (massless regime) and the representation theory of the quantum affine algebra ${\cal U}_q (\hat{sl}_2)$ together with the corner transfer matrix approach (massive regime).

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N. Kitanine, J. M. Maillet, V. Terras. 1999-07-23. Correlation functions of the XXZ Heisenberg spin-1/2 chain in a magnetic field. https://doi.org/10.1016/s0550-3213(99)00619-7

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