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d-Mott phases in one and two dimensions

A. Laeuchli·C. Honerkamp·T. M. Rice
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Abstract

We use exact diagonalization to determine the spectrum of reduced Hamiltonians based on renormalization group flows to strong coupling. For the half-filled two-leg Hubbard ladder we reproduce the known insulating d-Mott groundstate with spin and charge gaps. For the saddle point regions of the two-dimensional Hubbard model near half-filling we find a crossover to a similar strong coupling state, which truncates the Fermi surface near the saddle points. At lower scales d-wave superconductivity appears on the remaining Fermi surface.

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A. Laeuchli, C. Honerkamp, T. M. Rice. 2004-01-26. d-Mott phases in one and two dimensions. https://doi.org/10.1103/physrevlett.92.037006

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