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arXiv · 2308.13181

Emergent $\mathbb{Z}_2$ symmetry near a CDW multicritical point

Steven A. Kivelson·Akshat Pandey·Anisha G. Singh·Aharon Kapitulnik·Ian R. Fisher
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Abstract

We consider the critical behavior associated with incommensurate unidirectional charge-density-wave ordering in a weakly orthorhombic system subject to uniaxial strain as an experimentally significant example of $U(1)\times U(1)$ multicriticality. We show that, depending on microscopic details, the phase diagram can have qualitatively different structures which can involve a vestigial meta-nematic critical point, a pair of tricritical points, a decoupled tetracritical point, or (at least at mean-field level) a bicritical point. We analyze the emergent symmetries in the critical regime and find that these can -- at least in some cases -- involve an emergent $\mathbb{Z}_2$ order parameter symmetry.

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BibTeXRIS

Steven A. Kivelson, Akshat Pandey, Anisha G. Singh, Aharon Kapitulnik, Ian R. Fisher. 2023-08-25. Emergent $\mathbb{Z}_2$ symmetry near a CDW multicritical point. https://doi.org/10.1103/physrevb.108.205141

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