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Insulating phases of the infinite-dimensional Hubbard model

David E. Logan·Michael P. Eastwood·Michael A. Tusch
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Abstract

A theory is developed for the T=0 Mott-Hubbard insulating phases of the infinite-dimensional Hubbard model at half-filling, including both the antiferromagnetic (AF) and paramagnetic (P) insulators. Local moments are introduced explicitly from the outset, enabling ready identification of the dominant low energy scales for insulating spin- flip excitations. Dynamical coupling of single-particle processes to the spin-flip excitations leads to a renormalized self-consistent description of the single-particle propagators that is shown to be asymptotically exact in strong coupling, for both the AF and P phases. For the AF case, the resultant theory is applicable over the entire U-range, and is discussed in some detail. For the P phase, we consider in particular the destruction of the Mott insulator, the resultant critical behaviour of which is found to stem inherently from proper inclusion of the spin-flip excitations.

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David E. Logan, Michael P. Eastwood, Michael A. Tusch. 1997-06-06. Insulating phases of the infinite-dimensional Hubbard model. https://doi.org/10.1088/0953-8984%2F9%2F20%2F019

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