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Physical Review Letters

Boundary Conditions for Renormalization-Group Equations in One-Dimensional Fermi Gas

A. I. Larkin, Josef Sak

Published Oct 17, 1977• 29 citations
Publisher

Abstract

The energy gap in one-dimensional Fermi systems with weak attractive interaction is expressed in terms of the parameters of the Hamiltonian and the electron density. The models of Hubbard and phonon-mediated interactions are studied in detail. The result for the Hubbard model is compared with numerical calculations.
DOI
10.1103/physrevlett.39.1025

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