We present an exact diagonalization study of the single-particle spectral function in the so-called t- ${\mathrm{t}}^{|\mathrm{I}\mathrm{H}}$ -t\ensuremath{''}-J model in two dimensions. As a key result, we find that hole doping leads to a major reconstruction of the quasiparticle band structure near (\ensuremath{\pi},0): whereas for the undoped system the quasiparticle states near (\ensuremath{\pi},0) are deep below the top of the band near (\ensuremath{\pi}/2,\ensuremath{\pi}/2), hole doping shifts these states up to ${\mathrm{E}}_{\mathrm{F}}$ , resulting in extended flat band regions close to ${\mathrm{E}}_{\mathrm{F}}$ and around (\ensuremath{\pi},0).We present an exact diagonalization study of the single-particle spectral function in the so-called t-${\mathrm{t}}^{|\mathrm{I}\mathrm{H}}$-t\ensuremath{''}-J model in two dimensions. As a key result, we find that hole doping leads to a major reconstruction of the quasiparticle band structure near (\ensuremath{\pi},0): whereas for the undoped system the quasiparticle states near (\ensuremath{\pi},0) are deep below the top of the band near (\ensuremath{\pi}/2,\ensuremath{\pi}/2), hole doping shifts these states up to ${\mathrm{E}}_{\mathrm{F}}$, resulting in extended flat band regions close to ${\mathrm{E}}_{\mathrm{F}}$ and around (\ensuremath{\pi},0).

arXiv:cond-mat/9611033Physical review. B, Condensed matterFeb 1, 199765 citations

Band structure, magnetic fluctuations, and quasiparticle nature of the two-dimensional three-band Hubbard model

Hong-Qiang Ding, G. H. Lang, William A. Goddard

A single hole doped into the ${\mathrm{CuO}}_{2}$ plane of a high- ${\mathit{T}}_{\mathit{c}}$ superconductor is studied via exact calculations of the three-band Hubbard model (large-U limit) on a 4\ifmmode\times\else\texttimes\fi{}4 periodic cluster. The quasiparticle band has its bottom at k=(\ensuremath{\pi}/2,\ensuremath{\pi}/2) and disperses strongly towards \ensuremath{\Gamma} and X with a dispersion 1.7 ${\mathit{J}}_{\mathit{d}\mathit{d}}$ =0.22 eV. The quasiparticle has a nearly isotropic effective mass (\ensuremath{\sim}4 ${\mathit{m}}_{\mathit{e}}$ ) and the dressing effects are well localized (\ensuremath{\sim}8 \AA{}) with characteristic features of both the three-spin polaron and the Zhang-Rice singlet (although solutions of the t-J model are substantially different).A single hole doped into the ${\mathrm{CuO}}_{2}$ plane of a high-${\mathit{T}}_{\mathit{c}}$ superconductor is studied via exact calculations of the three-band Hubbard model (large-U limit) on a 4\ifmmode\times\else\texttimes\fi{}4 periodic cluster. The quasiparticle band has its bottom at k=(\ensuremath{\pi}/2,\ensuremath{\pi}/2) and disperses strongly towards \ensuremath{\Gamma} and X with a dispersion 1.7${\mathit{J}}_{\mathit{d}\mathit{d}}$=0.22 eV. The quasiparticle has a nearly isotropic effective mass (\ensuremath{\sim}4${\mathit{m}}_{\mathit{e}}$) and the dressing effects are well localized (\ensuremath{\sim}8 \AA{}) with characteristic features of both the three-spin polaron and the Zhang-Rice singlet (although solutions of the t-J model are substantially different).

Physical review. B, Condensed matterDec 1, 199214 citations

29a-J-7 Quasiparticle Momentum Distributions in the t-J Model

理西本, 幸則太田, R. Eder

日本物理学会講演概要集Mar 17, 19970 citations

Quasiparticle band structure and density-functional theory: Single-particle excitations and band gaps in lattice models

D. W. Hess, Joseph W. Serene

We compare the quasiparticle band structure for a model insulator obtained from the fluctuation exchange approximation (FEA) with the eigenvalues of the corresponding density-functional theory (DFT) and local-density approximation (LDA). The discontinuity in the exchange-correlation potential for this model is small and the FEA and DFT band structures are in good agreement. In contrast to conventional wisdom, the LDA for this model overestimates the size of the band gap. We argue that this is a consequence of an FEA self-energy that is strongly frequency dependent, but essentially local.We compare the quasiparticle band structure for a model insulator obtained from the fluctuation exchange approximation (FEA) with the eigenvalues of the corresponding density-functional theory (DFT) and local-density approximation (LDA). The discontinuity in the exchange-correlation potential for this model is small and the FEA and DFT band structures are in good agreement. In contrast to conventional wisdom, the LDA for this model overestimates the size of the band gap. We argue that this is a consequence of an FEA self-energy that is strongly frequency dependent, but essentially local.

arXiv:cond-mat/9902360Physical review. B, Condensed matterJun 15, 199912 citations

Quasiparticle spectra in a tJ model with electron-phonon interactions

Peter Horsch, A. Ramšak, Peter Fulde

Physica B Condensed MatterFeb 1, 19941 citation

We present an exact diagonalization study of the single-particle spectral function in the so-called t-

{\mathrm{t}}^{|\mathrm{I}\mathrm{H}}

-t\ensuremath{''}-J model in two dimensions. As a key result, we find that hole doping leads to a major reconstruction of the quasiparticle band structure near (\ensuremath{\pi},0): whereas for the undoped system the quasiparticle states near (\ensuremath{\pi},0) are deep below the top of the band near (\ensuremath{\pi}/2,\ensuremath{\pi}/2), hole doping shifts these states up to

{\mathrm{E}}_{\mathrm{F}}

, resulting in extended flat band regions close to

{\mathrm{E}}_{\mathrm{F}}

and around (\ensuremath{\pi},0).

A single hole doped into the

{\mathrm{CuO}}_{2}

plane of a high-

{\mathit{T}}_{\mathit{c}}

superconductor is studied via exact calculations of the three-band Hubbard model (large-U limit) on a 4\ifmmode\times\else\texttimes\fi{}4 periodic cluster. The quasiparticle band has its bottom at k=(\ensuremath{\pi}/2,\ensuremath{\pi}/2) and disperses strongly towards \ensuremath{\Gamma} and X with a dispersion 1.7

{\mathit{J}}_{\mathit{d}\mathit{d}}

=0.22 eV. The quasiparticle has a nearly isotropic effective mass (\ensuremath{\sim}4

{\mathit{m}}_{\mathit{e}}

) and the dressing effects are well localized (\ensuremath{\sim}8 \AA{}) with characteristic features of both the three-spin polaron and the Zhang-Rice singlet (although solutions of the t-J model are substantially different).