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Journal of Low Temperature Physics

, Volume 99, Issue 3–4, pp 481–486 | Cite as

Exact diagonalisation studies of strongly correlated 2D lattice fermions

  • Didier Poilblanc
Various Aspects of Strongly Correlated Electrons

Abstract

The T=0 phase diagram of the planar t-J model with small doping is investigated by exact diagonalisations of square clusters with up to 32 sites. At half-filling, the single hole quasi-particule weight vanishes in the strong correlation limit J → 0 while the quasi-particle mass diverges (like 1/J). However, the spectral function shows weight distributed over a large energy range (∼ 7t) and a pronounced structure in momentum space which supports the composite particle picture of the hole. For J/t > J/tB,2 the effective attractive force between holes leads to bound-pairs formation. The hole-hole and hole pair-hole pair binding energies calculated on the√26 ×√26 (1/N) to physical quantities. The free-particle result at U = 0 is then recovered for arbitrary doping even with the inclusion of fluctuations. Numerical results are shown for finite values of U.

PACS numbers

74.12.−h 71.27.+a 71.55.−i 

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Copyright information

© Plenum Publishing Corporation 1995

Authors and Affiliations

  • Didier Poilblanc
    • 1
  1. 1.Laboratoire de Physique QuantiqueUniversité Paul SabotierToulouseFrance

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