Critical nucleation mesh-size of coarsening transient colloidal networks.

Isotropic magnetic field modulations cause the formation and coarsening of transient two dimensional paramagnetic colloidal networks. We show that the virgin transient network consists of sub- and supercritical meshes. In the initial coarsening process subcritical meshes shrink while supercritical meshes grow. While the coarsening is a truly non-equilibrium process, the critical nucleation size is independent of transport coefficients and can be theoretically described by the competition of first order long range collective dipolar interactions and short range second order dipolar pair correlations.