Umb. Marconi et A. Petri, TIME-DEPENDENT GINZBURG-LANDAU MODEL IN THE ABSENCE OF TRANSLATIONAL INVARIANCE - NONCONSERVED ORDER-PARAMETER DOMAIN GROWTH, Journal of physics. A, mathematical and general, 30(4), 1997, pp. 1069-1088
We have determined the static and dynamical properties of the Ginzburg
-Landau model, with global coupling of the spherical type, on some non
-translationally invariant lattices. Our solutions show that, in agree
ment with general theorems, fractal lattices with finite ramification
do not display a finite temperature phase transition for any embedding
dimension, d. On the other hand, the dynamical behaviour associated w
ith the phase ordering dynamics of a non-conserved order parameter is
non-trivial. Our analysis reveals that the domain size R grows in time
as R(t) similar to t(z) and relates this exponent to the three expone
nts which characterize the static and dynamical properties of fractal
structures, namely the fractal dimension of the lattice d(f), the rand
om walk dimension d(w) and the spectral dimension d(s). We also presen
t a brief renormalization group treatment of the model. Finally, we ha
ve considered lattices with infinite ramification numbers which have s
pectral dimensions larger that 2 and show a finite temperature phase t
ransition.