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The Spectrum-Generating Algebra of the Van Hove Scenario is SO(8)

R. S. Markiewicz·M. T. Vaughn
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Abstract

The various nesting and pairing instabilities of the generalized Van Hove scenario can be classified via an SO(8) spectrum-generating algebra. An SO(6) subgroup is an approximate symmetry group of the model, having two 6-dimensional representations (`superspins'). This group contains as subgroups both the SO(5) and SO(4) groups found by Zhang, while one superspin is a combination of Zhang's 5-component superspin with a flux phase instability; the other includes a charge density wave instability plus s-wave superconductivity. This is the smallest group which can describe both striped phases and superconductivity.

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R. S. Markiewicz, M. T. Vaughn. 1998-02-06. The Spectrum-Generating Algebra of the Van Hove Scenario is SO(8). https://arxiv.org/abs/cond-mat/9802078

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