Inhomogeneously doped two-leg ladder systems
Abstract
A chemical potential difference between the legs of a two-leg ladder is found to be harmful for Cooper pairing. The instability of superconductivity in such systems is analyzed by compairing results of various analytical and numerical methods. Within a strong coupling approach for the t-J model, supplemented by exact numerical diagonalization, hole binding is found unstable beyond a finite, critical chemical potential difference. The spinon-holon mean field theory for the t-J model shows a clear reduction of the the BCS gaps upon increasing the chemical potential difference leading to a breakdown of superconductivity. Based on a renormalization group approach and Abelian bosonization, the doping dependent phase diagram for the weakly interacting Hubbard model with different chemical potentials was determined.
Cite
@article{arxiv.cond-mat/0206344,
title = {Inhomogeneously doped two-leg ladder systems},
author = {Stefan Wessel and Martin Indergand and Andreas Laeuchli and Urs Ledermann and Manfred Sigrist},
journal= {arXiv preprint arXiv:cond-mat/0206344},
year = {2007}
}
Comments
Revtex4, 11 pages, 7 figures