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arXiv · 1103.3315

Phases of the infinite U Hubbard model

Li Liu·Hong Yao·Erez Berg·Steven A. Kivelson
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Abstract

We apply the density matrix renormalization group (DMRG) to study the phase diagram of the infinite U Hubbard model on 2-, 4-, and 6-leg ladders. Where the results are largely insensitive to the ladder width, we consider the results representative of the 2D square lattice model. We find a fully polarized ferromagnetic Fermi liquid phase when n, the density of electrons per site, is in the range 1>n>n_F ~ 4/5. For n=3/4 we find an unexpected commensurate insulating "checkerboard" phase with coexisting bond density order with 4 sites per unit cell and block spin antiferromagnetic order with 8 sites per unit cell. For 3/4 > n, the wider ladders have unpolarized groundstates, which is suggestive that the same is true in 2D.

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Li Liu, Hong Yao, Erez Berg, Steven A. Kivelson. 2011-03-16. Phases of the infinite U Hubbard model. https://doi.org/10.1103/physrevlett.108.126406

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