Nota de FísicaPublicado
Disordered D-vector model: mean field renormalization group treatment
M.L. Lyra; S. Coutinho
1987
Datos de la publicación
- Autores
- M.L. Lyra; S. Coutinho
- Tipo
- Nota de Física
- Estado
- Publicado
- Fecha de publicación
- 1987
- Descripción
- The mean field renormalization group is applied to study crit ical temperatures of the quenched (F,AF and SG phases) an annealed (F and AF phases) disordered D-vector model. The phase diagrams, critical temperature against concentration are analytically calculated, plotted and analyzed for the Ising (D =1) , Heisenberg (D =3) and <math>D\rightarrow \infty</math> cases for several values of the competing para meter and coordination number and for a particular distribution function. Reentrancies and limiting slope at <math>p_c\,\!</math> of the f erroand antiferromagnetic boundaries are studied in details. There is a critical value of the competing parameter for the existence of reentrancies in these lines. The limiting slope at <math>p_c\,\!</math> is lower bounded by the <math>D\rightarrow \infty</math> value. A mapping is applied to study phase diagram of the antiferromagnetic Ising model with random decorating competing D-vector bond spins. It is found that for a fixed competing parameter there is a lower critical dimensionality <math>D_c\,\!</math> for the stability of the ferromagnetic and spin glass phases. In all diagrams reentrancies are more prominent for higherdimensionalities. The present results are strictly equivalent to the exact results on the Bethe lattice.
- Año
- 1987
- Número
- CBPF-NF-052/87
- Vínculo con tesis
- No
- Vínculo con beca
- No