The ground state of the two-leg Hubbard ladder: a density--matrix renormalization group study
Abstract
We present density-matrix renormalization group results for the ground state properties of two-leg Hubbard ladders. The half-filled Hubbard ladder is an insulating spin-gapped system, exhibiting a crossover from a spin-liquid to a band-insulator as a function of the interchain hopping matrix element. When the system is doped, there is a parameter range in which the spin gap remains. In this phase, the doped holes form singlet pairs and the pair-field and the "" density correlations associated with pair density fluctuations decay as power laws, while the "" charge density wave correlations decay exponentially. We discuss the behavior of the exponents of the pairing and density correlations within this spin gapped phase. Additional one-band Luttinger liquid phases which occur in the large interband hopping regime are also discussed.
Keywords
Cite
@article{arxiv.cond-mat/9601047,
title = {The ground state of the two-leg Hubbard ladder: a density--matrix renormalization group study},
author = {R. M. Noack and S. R. White and D. J. Scalapino},
journal= {arXiv preprint arXiv:cond-mat/9601047},
year = {2009}
}
Comments
14 pages, 18 figures, uses Revtex with epsfig to include the figures