The T=0 phase diagram for two Hubbard chains with interchain hopping t and on-site repulsion U is derived within a renormalization-group (RG) approach. We explicitly allow for renormalization of the Fermi momenta. A nonzero t drives the chains towards strong coupling, and only for large t 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 (t0), not confining, for small U, and another with t=0, confining, for large U. Numerical diagonalizations for a small cluster support the RG results
Strong-coupling phases of two Hubbard chains with interchain hopping / Fabrizio, Michele; Parola, A; Tosatti, E.. - In: PHYSICAL REVIEW. B, CONDENSED MATTER. - ISSN 0163-1829. - 46:5(1992), pp. 3159-3162. [10.1103/PhysRevB.46.3159]
Strong-coupling phases of two Hubbard chains with interchain hopping
Fabrizio, Michele;
1992-01-01
Abstract
The T=0 phase diagram for two Hubbard chains with interchain hopping t and on-site repulsion U is derived within a renormalization-group (RG) approach. We explicitly allow for renormalization of the Fermi momenta. A nonzero t drives the chains towards strong coupling, and only for large t 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 (t0), not confining, for small U, and another with t=0, confining, for large U. Numerical diagonalizations for a small cluster support the RG resultsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
