Doping- and temperature-dependent electronic structure and spin dynamics in the Hubbard model on a square lattice within cluster perturbation theory

V. I. Kuz'min; S. G. Ovchinnikov

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arXiv · 2606.01716

Doping- and temperature-dependent electronic structure and spin dynamics in the Hubbard model on a square lattice within cluster perturbation theory

V. I. Kuz'min·S. G. Ovchinnikov

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Abstract

The doping and temperature dependencies of the electronic structure and the dynamic spin susceptibility of the Hubbard model on a square lattice are studied within cluster perturbation theory (CPT). The most general features of both electronic and spin spectra qualitatively agree with the experimental data on cuprates. Generalized mean-field calculations of the electronic structure using static short-range magnetic correlations from CPT are also implemented and compared with the results of CPT, allowing us to discuss the role of short-range antiferromagnetism in the formation of the pseudogap.

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V. I. Kuz'min, S. G. Ovchinnikov. 2026-06-01. Doping- and temperature-dependent electronic structure and spin dynamics in the Hubbard model on a square lattice within cluster perturbation theory. https://arxiv.org/abs/2606.01716

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