| Autor: |
M. E. Simon, A. A. Aligia, Cristian D. Batista |
| Rok vydání: |
1994 |
| Předmět: |
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| Zdroj: |
Physical review. B, Condensed matter. 49(18) |
| ISSN: |
0163-1829 |
| Popis: |
We perform a consistent low-energy reduction of the three-band Hubbard model ${\mathit{H}}_{3\mathit{b}}$ to an effective one-band model ${\mathit{H}}_{1\mathit{b}}$, using as an intermediate step a renormalized effective spin-fermion model ${\mathit{H}}_{\mathrm{sf}}$ in which ${\mathrm{Cu}}^{+}$ and ${\mathrm{Cu}}^{3+}$ configurations are contained as virtual states. We map ${\mathit{PH}}_{\mathrm{sf}}$P into ${\mathit{H}}_{1\mathit{b}}$ using two projectors P onto different Zhang-Rice singlets: (1) orthogonal singlets constructed using O Wanner functions, (2) nonorthogonal singlets. In case 1 (2) the mapping is almost exact (exact as shown before by Zhang) if direct O-O hopping and the ${\mathrm{Cu}}^{3+}$ (${\mathrm{Cu}}^{+}$) configuration can be neglected. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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