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Integrable versus Non-Integrable Spin Chain Impurity Models

E. S. Sorensen·S. Eggert·I. Affleck
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Abstract

Recent renormalization group studies of impurities in spin-1/2 chains appear to be inconsistent with Bethe ansatz results for a special integrable model. We study this system in more detail around the integrable point in parameter space and argue that this integrable impurity model corresponds to a non-generic multi-critical point. Using previous results on impurities in half-integer spin chains, a consistent renormalization group flow and phase diagram is proposed.

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E. S. Sorensen, S. Eggert, I. Affleck. 1993-06-01. Integrable versus Non-Integrable Spin Chain Impurity Models. https://doi.org/10.1088/0305-4470%2F26%2F23%2F023

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