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arXiv · hep-th/9210096

Non-linear Field Theory of a Frustrated Heisenberg Spin Chain

Sumathi Rao·Diptiman Sen
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Abstract

We derive a continuum field theory for the Majumdar-Ghosh model in the large-$S$ limit, where the field takes values in the manifold of the $SO(3)$ group. No topological term is induced in the action and the cases for integer spin and half-integer spin appear to be indistinguishable. A one-loop $β-$function calculation indicates that the theory flows towards a strong coupling (disordered) phase at long distances. This is verified in the large-$N$ limit, where all excitations are shown to be massive. (Three figures not included)

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Sumathi Rao, Diptiman Sen. 1992-10-18. Non-linear Field Theory of a Frustrated Heisenberg Spin Chain. https://doi.org/10.1016/0550-3213(94)90407-3

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