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arXiv · 0707.2803

Deformed strings in the Heisenberg model

R. Hagemans·J. -S. Caux
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Abstract

We investigate solutions to the Bethe equations for the isotropic S = 1/2 Heisenberg chain involving complex, string-like rapidity configurations of arbitrary length. Going beyond the traditional string hypothesis of undeformed strings, we describe a general procedure to construct eigenstates including strings with generic deformations, discuss general features of these solutions, and provide a number of explicit examples including complete solutions for all wavefunctions of short chains. We finally investigate some singular cases and show from simple symmetry arguments that their contribution to zero-temperature correlation functions vanishes.

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R. Hagemans, J. -S. Caux. 2007-07-19. Deformed strings in the Heisenberg model. https://doi.org/10.1088/1751-8113/40/49/001

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