Phase growth in bistable systems with impurities
Autores: C. Echeverría, K. Tucci, M.G. Cosenza
Referencia:
Physical Review E, 77, 016204, (2008)
Abstract
A system of coupled chaotic bistable maps on a
lattice with randomly distributed impurities is
investigated as a model for studying the phenomenon
of phase growth in nonuniform media. The statistical
properties of the system are characterized by means
of the average size of spatial domains of equivalent
spin variables that define the phases. It is found that
the rate at which phase domains grow becomes smaller
when impurities are present and that the average size
of the resulting domains in the inhomogeneous state of
the system decreases when the density of impurities is
increased. The phase diagram showing regions where
homogeneous, heterogeneous, and chessboard patterns
occur on the space of parameters of the system is
obtained. A critical boundary that separates the regime
of slow growth of domains from the regime of fast growth
in the heterogeneous region of the phase diagram is
calculated. The transition between these two growth
regimes is explained in terms of the stability properties
of the local phase configurations. Our results show that
the inclusion of spatial inhomogeneities can be used as a
control mechanism for the size and growth velocity of
phase domains forming in spatiotemporal systems.
|