Fractionalized Fermi liquids with the ghost-Gutzwiller Ansatz

Ivan Pasqua; Carlos Mejuto-Zaera; Michele Fabrizio

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arXiv · 2607.12410

Fractionalized Fermi liquids with the ghost-Gutzwiller Ansatz

Ivan Pasqua·Carlos Mejuto-Zaera·Michele Fabrizio

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Abstract

Fractionalized Fermi liquids ($\mathrm{FL}^{\!*}$), elusive metallic states characterized by fractionalized quasiparticles alongside conventional ones and defying Luttinger's theorem, are prime candidates for the pseudogap regime of underdoped cuprates. We show that a $\mathrm{FL}^{\!*}$ phase emerges in the single-band $t$-$J$ model through a simple ghost-Gutzwiller Ansatz, optimized at the cost of a mean-field calculation. The resulting temperature-doping phase diagram encompasses a low-doping $\mathrm{FL}^{\!*}$, a $d$-wave superconducting dome, and an overdoped conventional Fermi liquid, thereby reproducing key qualitative features of cuprate phenomenology.

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Ivan Pasqua, Carlos Mejuto-Zaera, Michele Fabrizio. 2026-07-14. Fractionalized Fermi liquids with the ghost-Gutzwiller Ansatz. https://arxiv.org/abs/2607.12410

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