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arXiv · hep-th/9506141

The Large N Random Phase sine-Gordon Model

Michel Bauer·Denis Bernard
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Abstract

At large distances and in the low temperature phase, the quenched correlation functions in the 2d random phase sine-Gordon model have been argued to be of the form~: $ \bar {\vev{~[φ(x)-φ(0)]^2~}}_* = A (\log|x|) + B \ep^2 (\log|x|)^2 $, with $\ep=(T-T_c)$. However, renormalization group computations predict $B\not=0$ while variational approaches (which are supposed to be exact for models with a large number of components) give $B=0$. We introduce a large $N$ version of the random phase sine-Gordon model. Using non-Abelian bosonization and renormalization group techniques, we show that the correlation functions of our models have the above form but with a coefficient $B$ suppressed by a factor $1/N^3$ compared to $A$.

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Michel Bauer, Denis Bernard. 1995-06-21. The Large N Random Phase sine-Gordon Model. https://doi.org/10.1209/epl%2Fi1996-00329-2

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