Phase diagram of the one-dimensional extended Hubbard model with attractive and/or repulsive interactions at quarter filling

K. Penc, Frédéric Mila

Research output: Contribution to journalArticle

101 Citations (Scopus)

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.

Original languageEnglish
Pages (from-to)9670-9678
Number of pages9
JournalPhysical Review B
Volume49
Issue number14
DOIs
Publication statusPublished - 1994

Fingerprint

Hubbard model
Phase separation
Phase diagrams
phase diagrams
Variational techniques
Ground state
interactions
ground state

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Phase diagram of the one-dimensional extended Hubbard model with attractive and/or repulsive interactions at quarter filling. / Penc, K.; Mila, Frédéric.

In: Physical Review B, Vol. 49, No. 14, 1994, p. 9670-9678.

Research output: Contribution to journalArticle

@article{517ef88d18d64002839e806d0b5756ce,
title = "Phase diagram of the one-dimensional extended Hubbard model with attractive and/or repulsive interactions at quarter filling",
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.",
author = "K. Penc and Fr{\'e}d{\'e}ric Mila",
year = "1994",
doi = "10.1103/PhysRevB.49.9670",
language = "English",
volume = "49",
pages = "9670--9678",
journal = "Physical Review B-Condensed Matter",
issn = "0163-1829",
publisher = "American Physical Society",
number = "14",

}

TY - JOUR

T1 - Phase diagram of the one-dimensional extended Hubbard model with attractive and/or repulsive interactions at quarter filling

AU - Penc, K.

AU - Mila, Frédéric

PY - 1994

Y1 - 1994

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=0001046582&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001046582&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.49.9670

DO - 10.1103/PhysRevB.49.9670

M3 - Article

VL - 49

SP - 9670

EP - 9678

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 14

ER -