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arXiv · 2207.00829

SU(2) gauge theory of the pseudogap phase in the two-dimensional Hubbard model

Pietro M. Bonetti·Walter Metzner
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Abstract

We present a SU(2) gauge theory of fluctuating magnetic order in the two-dimensional Hubbard model. The theory is based on a fractionalization of electrons in fermionic chargons and bosonic spinons. The chargons undergo N\'eel or spiral magnetic order below a density dependent transition temperature $T^*$. Fluctuations of the spin orientation are described by a non-linear sigma model obtained from a gradient expansion of the spinon action. The spin stiffnesses are computed from a renormalization group improved random phase approximation. Our approximations are applicable for a weak or moderate Hubbard interaction. The spinon fluctuations prevent magnetic long-range order of the electrons at any finite temperature. The phase with magnetic chargon order exhibits many features characterizing the pseudogap regime in high-$T_c$ cuprates: a strong reduction of charge carrier density, a spin gap, Fermi arcs, and electronic nematicity.

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Pietro M. Bonetti, Walter Metzner. 2022-07-02. SU(2) gauge theory of the pseudogap phase in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevb.106.205152

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