Abstract
The T=0 phase diagram for two Hubbard chains with interchain hopping and on-site repulsion U is derived within a renormalization-group (RG) approach. We explicitly allow for renormalization of the Fermi momenta. A nonzero drives the chains towards strong coupling, and only for large is a Luttinger liquid recovered. By use of weak-coupling RG, a qualitative picture of the phase diagram can be obtained. Our calculations show two different strong-coupling regimes: one with nonvanishing effective interchain hopping (〈〉≠0), not confining, for small U, and another with 〈〉=0, confining, for large U. Numerical diagonalizations for a small cluster support the RG results.
- Received 3 March 1992
DOI:https://doi.org/10.1103/PhysRevB.46.3159
©1992 American Physical Society