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arXiv · 2606.02838

The pseudogap in high-$T_c$ superconductors from SU(2) gauge symmetry and dynamic correlation effects

I. A. Goremykin·A. A. Katanin
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Abstract

We consider the spectral properties of the two-dimensional Hubbard model, describing the electronic properties of high-$T_c$ compounds, within the SU(2) gauge theory, which assumes the separation of electronic degrees of freedom into those of spinon and chargon subsystems. We use the dynamic mean-field theory (DMFT) approach to describe magnetic long-range order in the chargon subsystem while also treating spinon fluctuations on top of this state. We show that DMFT supplemented by long-wavelength magnetic fluctuations is essential for describing the asymmetry in the damping between the inner and outer regions of the hole pockets and the resulting formation of Fermi arcs in the underdoped regime, especially at low hole doping. The underlying hole pockets in the chargon subsystem can be associated with those observed in quantum oscillation measurements.

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I. A. Goremykin, A. A. Katanin. 2026-06-01. The pseudogap in high-$T_c$ superconductors from SU(2) gauge symmetry and dynamic correlation effects. https://arxiv.org/abs/2606.02838

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