Surprises in the $O(N)$ models: nonperturbative fixed points, large $N$ limit and multi-criticality

Shunsuke Yabunaka; Bertrand Delamotte

doi:10.1103/physrevlett.119.191602

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arXiv · 1707.04383

Surprises in the $O(N)$ models: nonperturbative fixed points, large $N$ limit and multi-criticality

Shunsuke Yabunaka·Bertrand Delamotte

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Abstract

We find that the multicritical fixed point structure of the O($N$) models is much more complicated than widely believed. In particular, we find new nonperturbative fixed points in three dimensions ($d=3$) as well as at $N=\infty$. These fixed points come together with an intricate double-valued structure when they are considered as functions of $d$ and $N$. Many features found for the O($N$) models are shared by the O($N)\otimes$O(2) models relevant to frustrated magnetic systems.

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Shunsuke Yabunaka, Bertrand Delamotte. 2017-10-12. Surprises in the $O(N)$ models: nonperturbative fixed points, large $N$ limit and multi-criticality. https://doi.org/10.1103/physrevlett.119.191602

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