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Anomalous Scaling of the SO(8) Symmetric Phases in the Two-Leg Ladder

Hsiu-Hau Lin
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Abstract

We carry out a complete analytical stability study for the SO(8) symmetric phases in the weakly-interacting two-leg ladder. It is shown that the SO(8) symmetry is robust under generic perturbations. Since there are no fixed points in the one-loop renormalization group equations, the conventional classification of relevant and irrelevant perturbations fails in this case. A new classification is defined and explained in detail. It leads to the anomalous scaling in the ratios of excitation gaps and an universal exponent 1/3 is extracted. This new method is also applied to the well studied 2D Ising model and similar exponent is calculated.

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Hsiu-Hau Lin. 2000-10-01. Anomalous Scaling of the SO(8) Symmetric Phases in the Two-Leg Ladder. https://arxiv.org/abs/cond-mat/0010011

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