Defect-freezing and Defect-unbinding in the Vector Complex Ginzburg-Landau Equation.

We describe the dynamical behavior found in numerical solutions of
the Vector Complex Ginzburg-Landau equation in parameter values
where plane waves are stable. Topological defects in the system
are responsible for a rich behavior. At low coupling between the
vector components, a {sl frozen} phase is found, whereas a {sl
gas-like} phase appears at higher coupling. The transition is a
consequence of a defect unbinding phenomena. Entropy functions
display a characteristic behavior around the transition.