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Mott Transitions in the 2D Half-Filled Hubbard Model: Correlator Projection Method with Projective Dynamical Mean-Field Approximation

Shigeki Onoda·Masatoshi Imada
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Abstract

The 2D half-filled Hubbard model is studied by a nonperturbative analytic theory of correlator projection. The original dynamical mean-field approximation (DMFA) is reproduced at the first-order projection and then improved by systematic inclusion of spatial correlations at higher orders. A geometrical frustration induces a first-order Mott transition surface with a finite-temperature critical end curve. Growth of antiferromagnetic correlations gives single-particle spectra strongly modified from DMFA with shadow bands and flat dispersions observed in high-T_c cuprates.

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Shigeki Onoda, Masatoshi Imada. 2002-11-20. Mott Transitions in the 2D Half-Filled Hubbard Model: Correlator Projection Method with Projective Dynamical Mean-Field Approximation. https://doi.org/10.1103/physrevb.67.161102

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