ISSN:
1572-9613
Schlagwort(e):
ising model
;
percolation
;
mean-field theory
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Physik
Notizen:
Abstract The q=2 random cluster model is studied in the context of two mean-field models: the Bethe lattice and the complete graph. For these systems, the critical exponents that are defined in terms of finite clusters have some anomalous values as the critical point is approached from the high-density side, which vindicates the results of earlier studies. In particular, the exponent γ~′ which characterizes the divergence of the average size of finite clusters is 1/2, and ν~′, the exponent associated with the length scale of finite clusters, is 1/4. The full collection of exponents indicates an upper critical dimension of 6. The standard mean field exponents of the Ising system are also present in this model (ν′=1/2, γ′=1), which implies, in particular, the presence of two diverging length-scales. Furthermore, the finite cluster exponents are stable to the addition of disorder, which, near the upper critical dimension, may have interesting implications concerning the generality of the disordered system/correlation length bounds.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1023/A:1004555127906
Permalink
