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Quantitative expression of the spin gap via bosonization for a dimerized spin-1/2 chain

Edmond Orignac
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Abstract

Using results on the mass gap in the sine-Gordon model combined with the exact amplitudes in the bosonized representation of the Heisenberg spin-1/2 chain and one-loop renormalization group, we derive a quantitative expression for the gap in a dimerized spin-1/2 chain. This expression is shown to be in good agreement with recent numerical estimates when a marginally irrelevant perturbation is taken into account.

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Edmond Orignac. 2004-03-05. Quantitative expression of the spin gap via bosonization for a dimerized spin-1/2 chain. https://doi.org/10.1140/epjb%2Fe2004-00198-5

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