Bands renormalization and superconductivity in the strongly correlated Hubbard model using composite operators method

Abstract

We use the composite operator method (COM) to analyze the strongly correlated repulsive Hubbard model, investigating the effect of nearest-neighbor hoppings up to fourth order on a square lattice. We consider two sets of self-consistent equations, one enforcing the Pauli principle and the other imposing charge-charge, spin-spin, and pair-pair correlations using a decoupling scheme developed by L. Roth. We extract three distinct solutions from these equations: COM1 and COM2 by imposing the Pauli principle and one from Roth decoupling. An overview of the method studying the validity of particle-hole symmetry and the Luttinger theorem for each solution is presented. Additionally, we extend the initial basis to study superconductivity, concluding that it is induced by the Van Hove singularity. Finally, we include higher-order hoppings using realistic estimates for tight binding parameters and compare our results with ARPES measurements on cuprates.

References in corpus (5)

• The Hubbard model within the equations of motion approach
• Linear Response Theory and the Universal Nature of the Magnetic Excitation Spectrum of the Cuprates
• Breakdown of Fermi liquid behavior at the (π,π)=2k_F spin-density wave quantum-critical point: the case of electron-doped cuprates
• Pseudogap and the specific heat of high T${}_c$ superconductors: a Hubbard model in a n-pole approximation
• Local properties of the t-J model in a two-pole approximation within COM

Cited by in corpus (9)

• Spontaneous layer selective Mott phase in the bilayer Hubbard model
• Charge density wave solutions of the Hubbard model in the composite operator formalism
• The interplay between a pseudogap and superconductivity in a two-dimensional Hubbard model
• Strong pair-density-wave fluctuations in an exactly solvable doped Mott insulator
• Interplay between the charge density wave phase and a pseudogap under antiferromagnetic correlations
• Topological charge excitations and Green's function zeros in paramagnetic Mott insulators
• Impurity-induced Mott ring states and Mott zeros ring states in the Hubbard operator formalism
• Inverted duality of Hubbard model and an equation for the Green's function
• Probing quasiparticle excitations in a doped Mott insulator via Friedel oscillations