Long-wave fluctuations of the two-dimensional Heisenberg antiferromagnet

• Autor(a) principal: Belinicher, Victor
• Data de Publicação: 2000
• Outros Autores: Providência, João da
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/4532; https://doi.org/10.1016/S0921-4526(99)02832-X
• topic: Antiferromagnet; Disorder; Fluctuations

We have reduced the Heisenberg model for the quantum antiferromagnet in the leading approximation over 1/s to the spin-rotator model which represents some sort of quantum lattice rotator model. We perform the long-wavelength reduction of this spin-rotator model. An intermediate scale [Lambda] was introduced and the short-wavelength antiferromagnetic spin fluctuations were integrated out. As a result, we obtained the continuum nonlinear sigma model with some additional contributions. We presented arguments showing that this model is renormalizable in the framework of 1/N perturbation theory. We separated out all ultraviolet divergencies and expressed all parameters of the theory in terms of the parameters of the primary Heisenberg model, in the one-loop approximation.