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arXiv · 1204.4037

On Form Factors in nested Bethe Ansatz systems

Balazs Pozsgay·Willem-Victor van Gerven Oei·Marton Kormos
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Abstract

We investigate form factors of local operators in the multi-component Quantum Non-linear Schr\"odinger model, a prototype theory solvable by the so-called nested Bethe Ansatz. We determine the analytic properties of the infinite volume form factors using the coordinate Bethe Ansatz solution and we establish a connection with the finite volume matrix elements. In the two-component models we derive a set of recursion relations for the "magnonic form factors", which are the matrix elements on the nested Bethe Ansatz states. In certain simple cases (involving states with only one spin-impurity) we obtain explicit solutions for the recursion relations.

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Balazs Pozsgay, Willem-Victor van Gerven Oei, Marton Kormos. 2012-04-18. On Form Factors in nested Bethe Ansatz systems. https://doi.org/10.1088/1751-8113/45/46/465007

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