Two-dimensional Hubbard model in low electron density limit

Osamu Narikiyo, Yasumasa Hasegawa, Hidetoshi Fukuyama

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The two dimensional Hubbard model with repulsive interaction is studied in the tz.sbnd;matrixapproximation. At T = 0 the particle-particle correlation function and the tz.sbnd;matrix are obtained analytically so that it is shown that the tz.sbnd;matrix and hence the self-energy have no singularities in the upper half phase of the complex energy variable. The phase angle of the tz.sbnd;matrix δ(2kF+q,ω), in the limit q→0 and ω→0, is found to depend on the ratio ω/q and is not always zero. This non-vanishing phase angle results in the logarithmic correction to the imaginary part of the self-energy as ImΣ(kF,ε{lunate}) ∝ ε{lunate}2 lm |ε{lunate}|. However, the renormalization factor Z is finite at the Fermi surface suggesting that the stability of the Fermi liquid state at least within the conventional perturbation theory. The case of the attractive interaction has also been studied and the crossover from the Cooper pairing to the real-space pairing is indicated.

Original languageEnglish
Pages (from-to)1537-1538
Number of pages2
JournalPhysica C: Superconductivity and its applications
Volume185-189
Issue numberPART 3
DOIs
Publication statusPublished - Dec 1 1991
Externally publishedYes

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Hubbard model
two dimensional models
Carrier concentration
phase shift
matrices
Fermi liquids
Fermi surface
Fermi surfaces
energy
crossovers
perturbation theory
interactions

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering

Cite this

Two-dimensional Hubbard model in low electron density limit. / Narikiyo, Osamu; Hasegawa, Yasumasa; Fukuyama, Hidetoshi.

In: Physica C: Superconductivity and its applications, Vol. 185-189, No. PART 3, 01.12.1991, p. 1537-1538.

Research output: Contribution to journalArticle

Narikiyo, Osamu ; Hasegawa, Yasumasa ; Fukuyama, Hidetoshi. / Two-dimensional Hubbard model in low electron density limit. In: Physica C: Superconductivity and its applications. 1991 ; Vol. 185-189, No. PART 3. pp. 1537-1538.
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