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Large-n Limit of N=2 Supersymmetric Q^n Model in Two Dimensions

Kiyoshi Higashijima·Tetsuji Kimura·Muneto Nitta·Makoto Tsuzuki
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Abstract

We investigate non-perturbative structures of the two-dimensional N=2 supersymmetric nonlinear sigma model on the quadric surface Q^{n-2}(C) = SO(n)/SO(n-2)xU(1), which is a Hermitian symmetric space, and therefore Kahler, by using the auxiliary field and large-n methods. This model contains two kinds of non-perturbatively stable vacua; one of them is the same vacuum as that of supersymmetric CP^{n-1} model, and the other is a new kind of vacuum, which has not yet been known to exist in two-dimensional nonlinear sigma models, the Higgs phase. We show that both of these vacua are asymptotically free. Although symmetries are broken in these vacua, there appear no massless Nambu-Goldstone bosons, in agreement with Coleman's theorem, due to the existence of two different mechanisms in these vacua, the Schwinger and the Higgs mechanisms.

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Kiyoshi Higashijima, Tetsuji Kimura, Muneto Nitta, Makoto Tsuzuki. 2001-02-21. Large-n Limit of N=2 Supersymmetric Q^n Model in Two Dimensions. https://doi.org/10.1143/ptp.105.261

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