| Revista: | Brazilian journal of physics |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000309131 |
| ISSN: | 0103-9733 |
| Autores: | Foglio, M. E1 |
| Instituciones: | 1Universidade Estadual de Campinas, Instituto de Fisica "Gleb Wataghin", Campinas, Sao Paulo. Brasil |
| Año: | 1997 |
| Periodo: | Dic |
| Volumen: | 27 |
| Número: | 4 |
| Paginación: | 644-659 |
| País: | Brasil |
| Idioma: | Inglés |
| Tipo de documento: | Artículo |
| Enfoque: | Experimental, aplicado |
| Resumen en inglés | It is sometimes convenient to emphasize the local aspects of a part of a crystalline system, and use the corresponding localized states to build a basis of the states of the whole system. In many cases it is only a subspace of these local states that is relevant, and the Hubbard operators provide a fairly simple way to write the corresponding projected Hamiltonian. Two examples of this type of treatment are presented int this work. The first is a Co2+ impurity in a MgO crystal interacting through a Jahn-Teller term with the crystal phonons, and it is shown how this interaction affects the electronic Raman scattering. The second is the Anderson lattice when the local electrons have an infinite Coulomb repulsion, and a diagrammatic expansion with cumulants is discussed. We propose a method to obtain approximate Green's functions for the Anderson lattice that employs the exact solutions of an atomic problem, and the corresponding spectral density of the local electrons is calculated |
| Disciplinas: | Física y astronomía |
| Palabras clave: | Física de materia condensada, Operadores Hubbard, Sistemas cristalinos, Función de Green, Red de Anderson |
| Keyword: | Physics and astronomy, Condensed matter physics, Hubbard operators, Crystalline systems, Green function, Anderson lattice |
| Texto completo: | Texto completo (Ver HTML) |
