Open AccessMetal–insulator transition in the antiferromagnetic state of the Hubbard model: analytical theory
Author(s) -
P. A. Igoshev,
V. Yu. Irkhin
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1389/1/012081
Subject(s) - condensed matter physics , antiferromagnetism , van hove singularity , phase transition , metal–insulator transition , slave boson , physics , hubbard model , square lattice , singularity , ground state , quantum mechanics , fermi level , ising model , electron , superconductivity , mathematics , mathematical analysis , electrical resistivity and conductivity
In the framework of numerical calculations and analytical expansion in the transfer integral between the next-nearest neighbors t’ and the direct antiferromagnetic (AFM) gap ∆, the metal–insulator transition criterion is obtained, the Hartree-Fock and slave boson approaches being used. In the case of a square lattice, there is an interval of t’ values, for which the metal-insulator transition is a first-order transition, which is due to the Van Hove singularity near the center of the band. For simple and body-centered cubic lattices, the transition from the insulator AFM state occurs to the phase of an AFM metal and is a second-order phase transition; it is followed by a transition to a paramagnetic metal. These results are modified when taking into account the intersite Heisenberg interaction which can induce first-order transitions.