Revue: | Brazilian journal of physics |
Base de datos: | PERIÓDICA |
Número de sistema: | 000168798 |
ISSN: | 0103-9733 |
Autores: | Leonel, S.A1 Pires, A.S.T2 |
Instituciones: | 1Universidade Federal de Juiz de Fora, Departamento de Física, Juiz de Fora, Minas Gerais. Brasil 2Universidade Federal de Minas Gerais, Departamento de Física, Belo Horizonte, Minas Gerais. Brasil |
Año: | 2000 |
Periodo: | Jun |
Volumen: | 30 |
Número: | 2 |
Paginación: | 428-431 |
País: | Brasil |
Idioma: | Inglés |
Tipo de documento: | Artículo |
Enfoque: | Analítico |
Resumen en inglés | We use the self-consistent harmonic approximation (SCHA) to study static properties of the two-dimensional quantum Heisenberg model with easy-axis anisotropy. We calculate the critical temperature as a function of the spin value, and compare with classical results. Specifically, we compare how the ratio of critical temperatures varies as a function of the spin S in the quantum and classical cases, for afixed anisotropy parameter. We see that, for values of spin near 5/2, the classical result approximates to the quantum results and the classical calculation is justified. We have also studied the behavior of the magnetization for very small anisotropies. We have shown that our magnetization curves do not present a plateau in the limit of very small anisotropies, as predicted by the real-space renormalization-group calculations |
Disciplinas: | Física y astronomía |
Palabras clave: | Física de materia condensada, Magnetos, Modelo de Heisenberg, Aproximación armónica, Espín, Modelo de Ising |
Keyword: | Physics and astronomy, Condensed matter physics, Magnets, Heisenberg model, Harmonic approximation, Spin, Ising model |
Texte intégral: | Texto completo (Ver HTML) |