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arXiv · 1512.06102

Spectral function of the 2D Hubbard model: a density matrix renormalization group plus cluster perturbation theory study

Chun Yang·Adrian E. Feiguin
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Abstract

We study the spectral function of the 2D Hubbard model using cluster perturbation theory, and the density matrix renormalization group as a cluster solver. We reconstruct the two-dimensional dispersion at, and away from half-filling using 2xL ladders, with L up to 80 sites, yielding results with unprecedented resolution in excellent agreement with quantum Monte Carlo. The main features of the spectrum can be described with a mean-field dispersion, while kinks and pseudogap traced back to scattering between spin and charge degrees of freedom.

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Chun Yang, Adrian E. Feiguin. 2015-12-18. Spectral function of the 2D Hubbard model: a density matrix renormalization group plus cluster perturbation theory study. https://doi.org/10.1103/physrevb.93.081107

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