Naslov
Spectral Properties Of Two-Dimensional Hubbard Model

Autori
Entel, Peter ; Grabowski, Stefan ; Zlatić, Veljko ; Ikeda, M.A.

Izvornik
Molecular Physics Reports (1505-1250) X (1997); 45-58

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
strongly interacting electrons; spectral properties; cuprates; Hubbard model

Sažetak
We review results for the spectral function A(k, omega ) of the two-dimensional Hubbard model obtained by different methods. In particular we show that characteristic features like shift of spectral weight, band narrowing around the van-Hove singularities, and lifetime effects as obtained by Quantum-Monte-Carlo simulations performed at high-temperatures, are also present at low temperatures. Second order perturbation theory with respect to U/t allows to study these effects in detail. We find that band narrowing effects are most pronounced in the single-band Hubbard model, whereas the narrowing is much reduced in the three-band model for a single CuO/sub 2/ layer due to overlapping oxygen orbitals. Perturbation theory also allows to discuss the impact of correlations on the particle-hole susceptibility and the electron-phonon interaction. We will briefly discuss results for the spectral function alpha /sup 2/F( omega ) originating from the electron-phonon interaction obtained by band-structure calculations using the Local Density Approximation.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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