Non - linear Field Theory of a Frustrated Heisenberg Spin Chain
نویسندگان
چکیده
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. *
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