The singular value decomposition technique is used to reconstruct the electronic spectral weight function for a half-filled Hubbard model with on-site repulsion U=4t from Quantum Monte Carlo data. A two-band structure for the single-particle excitation spectrum is found to persist as the lattice size exceeds the spin-spin correlation length. The observed bands are flat in the vicinity of the (0,π),(π,0) points in the Brillouin zone, in accordance with experimental data for high-temperature superconducting compounds.
@article{arxiv.cond-mat/9501119,
title = {Spectral weight function for the half-filled Hubbard model: a singular value decomposition approach},
author = {C. E. Creffield and E. G. Klepfish and E. R. Pike and Sarben Sarkar},
journal= {arXiv preprint arXiv:cond-mat/9501119},
year = {2016}
}