Phase diagram of the one-dimensional extended Hubbard model with attractive and/or repulsive interactions at quarter filling
- 1 April 1994
- journal article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 49 (14), 9670-9678
- https://doi.org/10.1103/physrevb.49.9670
Abstract
We study the phase diagram of the one-dimensional U-V model at quarter filling in the most general case where the on-site and first-neighbor interactions U and V can be both attractive and repulsive. The results have been obtained using exact diagonalization of small clusters and variational techniques, as well as exact results in various limits. We have analyzed four properties of the ground state: (i) whether it is insulating or metallic; (ii) whether it is homogeneous or phase separated; (iii) whether it has a spin gap; (iv) whether it has dominant superconducting fluctuations. With eight phases, the resulting phase diagram is unexpectedly rich. The four phases not found in the weak coupling limit are: (i) an insulating phase when U and V are large enough; (ii) a region of phase separation when V is attractive; (iii) another region of phase separation when V is large enough and U small; (iv) a region with dominant superconducting fluctuations when V is intermediate and U small. The actual nature of this last plase, which has pairs but no spin gap, is not fully clear yet.Keywords
This publication has 25 references indexed in Scilit:
- Possible Observation of a Luttinger-Liquid Behaviour from Photoemission Spectroscopy of One-Dimensional Organic ConductorsEurophysics Letters, 1993
- Phase Diagram of the One-Dimensional Extended Hubbard Model at Quarter-FillingEurophysics Letters, 1993
- Nuclear relaxation and electronic correlations in quasi-one-dimensional organic conductors. II. ExperimentsJournal de Physique I, 1993
- Unusual photoemission spectral function of quasi-one-dimensional metalsPhysical Review Letters, 1991
- CORRELATED FERMIONS IN ONE DIMENSIONInternational Journal of Modern Physics B, 1991
- Correlation exponents and the metal-insulator transition in the one-dimensional Hubbard modelPhysical Review Letters, 1990
- Asymptotic spin-spin correlations of theU→∞ one-dimensional Hubbard modelPhysical Review Letters, 1990
- Real-space scaling methods applied to an interacting fermion HamiltonianPhysical Review B, 1981
- The Fermi gas model of one-dimensional conductorsAdvances in Physics, 1979
- Absence of Mott Transition in an Exact Solution of the Short-Range, One-Band Model in One DimensionPhysical Review Letters, 1968