Physical Review Letters
2pF and 4pF Instabilities in the One-Dimensional Electron Gas
J. E. Hirsch, Douglas J. Scalapino
Abstract
Charge- and spin-density response functions in the one-dimensional \textonequarter{}-filled extended Hubbard model have been studied by use of a Monte Carlo technique. The results show that Coulomb interactions suppress the $2{p}_{\mathrm{F}}$ charge-density singularity, while they enhance the $2{p}_{\mathrm{F}}$ spin-density singularity. The $4{p}_{\mathrm{F}}$ response is only appreciable if, in addition to on-site repulsion, longer-range interactions exist. The present results are compared with weak-coupling renormalization-group predictions.