English

Single-site entanglement at superconductor-insulator transition in the Hirsch model

Strongly Correlated Electrons 2007-05-23 v3 Statistical Mechanics Quantum Physics

Abstract

We investigate the transition to the insulating state in the one-dimensional Hubbard model with bond-charge interaction x (Hirsch model), at half-filling and T=0. By means of the density-matrix renormalization group algorithm the charge gap closure is examined by both standard finite size scaling analysis and looking at singularities in the derivatives of single-site entanglement. The results of the two techniques show that a quantum phase transition takes place at a finite Coulomb interaction u_c(x) for x>0.5. The region 0<u<u_c turns out to have a superconducting nature, at least for not too large x>x_c.

Keywords

Cite

@article{arxiv.cond-mat/0503600,
  title  = {Single-site entanglement at superconductor-insulator transition in the Hirsch model},
  author = {Alberto Anfossi and Cristian Degli Esposti Boschi and Arianna Montorsi and Fabio Ortolani},
  journal= {arXiv preprint arXiv:cond-mat/0503600},
  year   = {2007}
}

Comments

5 pages, 6 figures