English

The one-electron Green's function of the half-filled Hubbard model on a triangular lattice

Strongly Correlated Electrons 2007-05-23 v1 Materials Science

Abstract

The one-electron density of states for the half-filled Hubbard model on a triangular lattice is studied as a function of both temperature and Hubbard U using Quantum Monte Carlo. We find three regimes: (1) a strong-coupling Mott-Hubbard regime, characterized by a gap which persists even at high temperatures; (2) a weak-coupling paramagnetic regime, characterized by the absence of a pseudogap at any finite temperature; and (3) an intermediate-coupling (spiral) spin-density-wave regime, characterized by a pseudogap which appears when U is increased beyond a critical (temperature dependent) value. The behavior of the sqrt(3) times sqrt{3} adlayer structures on fourth-group semiconductor surfaces is briefly commented upon in the light of the above discussion.

Keywords

Cite

@article{arxiv.cond-mat/0103459,
  title  = {The one-electron Green's function of the half-filled Hubbard model on a triangular lattice},
  author = {M. C. Refolio and J. M. Lopez Sancho and J. Rubio},
  journal= {arXiv preprint arXiv:cond-mat/0103459},
  year   = {2007}
}

Comments

10 pages, 8 figures