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Critical properties of the double-frequency sine-Gordon model with applications

M. Fabrizio·A. O. Gogolin·A. A. Nersesyan
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Abstract

We study the properties of the double-frequency sine--Gordon model in the vicinity of the Ising quantum phase transition displayed by this model. Using a mapping onto a generalised lattice quantum Ashkin-Teller model, we obtain critical and nearly-off-critical correlation functions of various operators. We discuss applications of the double-sine-Gordon model to one-dimensional physical systems, like spin chains in a staggered external field and interacting electrons in a staggered potential.

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M. Fabrizio, A. O. Gogolin, A. A. Nersesyan. 2000-01-17. Critical properties of the double-frequency sine-Gordon model with applications. https://doi.org/10.1016/s0550-3213(00)00247-9

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