- Tytuł:
- Extended Hubbard Model in the Dimer Representation. I. Dimer Hamiltonian in the Large U Limit
- Autorzy:
-
Grabiec, B.
Matlak, M. - Powiązania:
- https://bibliotekanauki.pl/articles/2030513.pdf
- Data publikacji:
- 2002-04
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
71.10.-w
71.10.Ca
71.10.Fd - Opis:
- We consider the extended Hubbard model for the single cubic lattice and rewrite it in the form of interacting dimers, using the exact solution of the dimer problem. We analytically derive the second quantization form of the dimer Hamiltonian eliminating from the considerations unoccupied dimer energy levels in the large U limit (it is the only assumption). The resulting dimer Hamiltonian written with the use of the Hubbard operators and spin operators contains three terms, visualizing explicitly competing magnetic interactions (ferromagnetic, antiferromagnetic) as a generalization of the t-J model. The presented, nonperturbative method, can in principle be applied to the cluster of any size (e.g. one central atom and z its nearest neighbours). The use of the projection technique can further be applied in the case of a crystal to obtain the second quantization form of the extended Hubbard model for the sc lattice in the large U limit.
- Źródło:
-
Acta Physica Polonica A; 2002, 101, 4; 537-548
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł