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arXiv · 2301.10589

Hubbard bands, Mott transition and deconfinement in strongly correlated systems

V. Yu. Irkhin
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Abstract

The problem of deconfinement phases in strongly correlated systems is discussed. In space-time dimension $d=3+1$, a competition of confinement and Coulomb phases occurs, but in $d=2+1$ the confining phase dominates owing to monopole proliferation, but gapless fermion excitations can change the situation. Combining the Kotliar-Ruckenstein representation and fractionalized spin-liquid deconfinement picture, the Mott transition and Hubbard subbands are treated, general expressions in the case of an arbitrary bare band spectrum being obtained. The transition into a metallic state is determined by condensation of a gapless boson mode. The spectrum picture in the insulating state is considerably influenced by the spinon spin-liquid spectrum and hidden Fermi surface.

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V. Yu. Irkhin. 2023-01-25. Hubbard bands, Mott transition and deconfinement in strongly correlated systems. https://doi.org/10.1134/s002136402260269x

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