Original scientific paper

Ground state energy of 2D extended Hubbard model for finite size system with an exact diagonalization

S. Harir ; Laboratoire de Physique de la Matière Condensée, Faculté des Sciences Ben M'Sik, Université Hassan II-Mohammedia, Casablanca, Morocco
M. Bennai ; Laboratoire de Physique de la Matière Condensée, Faculté des Sciences Ben M'Sik, Université Hassan II-Mohammedia, Casablanca, Morocco; Groupement National de Physique des Hautes Energies, LabUFR-PHE, Rabat, Morocco
Y. Boughaleb ; Laboratoire de Physique de la Matière Condensée, Faculté des Sciences Ben M'Sik, Université Hassan II-Mohammedia, Casablanca, Morocco; LPMC, Faculté des Sciences d' El Jadida, Université Chouaib Doukkali, Morocco; Hassan II Academy of Sciences and Technology, Morocco

Abstract

Using an exact analytical diagonalization for an extended Hubbard model, we study the first nearest-neighbour repulsion effect on the behaviour of a two-dimensional system of finite size at low density of electrons. The obtained results show that the introduction of the nearest-neighbour off-site interaction allows the correlation effects to become more remarkable and to play an essential role in the electron dynamics, and this off-site interaction encourages the formation of double occupancies.

Keywords

extended Hubbard model; ground state; double occupation; gap energy

Hrčak ID:

302535

URI

https://hrcak.srce.hr/302535

Publication date:

1.7.2008.

Article data in other languages: croatian

Visits: 525 *