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arXiv · 1811.07374

Cuprates and center vortices: A QCD confinement mechanism in a high-Tc context

Abstract

It is suggested that the center vortex confinement mechanism, familiar in hadronic physics, may have some relevance to high-T$_\text{c}$ phenomena. We focus specifically on the transition from the superconducting phase to the pseudogap phase. There is evidence of a vortex liquid in the latter phase, in which the pairing responsible for superconductivity still exists, but superconductivity itself does not. An analogy, drawn from particle physics, may be the Higgs to confinement phase transition in an SU(N) gauge theory, where the confined phase is a vortex liquid, and the Higgs phase is a phase of a broken global $Z_N$ symmetry. We illustrate this idea with numerical simulations of a spatially asymmetric U(1) gauge-Higgs model, with lattice artifact monopoles suppressed. We show the existence of a Higgs (superconductor) to confinement (vortex liquid) phase, explicitly identifying vortices in lattice configurations generated in the confined phase, and showing that they produce an area-law falloff in planar Wilson loops, which may be measurable experimentally. The superconducting phase is a phase of broken global Z$_\text{2}$ symmetry.

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BibTeXRIS

Jeff Greensite, Kazue Matsuyama. 2019-11-07. Cuprates and center vortices: A QCD confinement mechanism in a high-Tc context. https://doi.org/10.1016/j.aop.2019.168011

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