title: Phase ordering with a global conservation law: Ostwald ripening and coalescence.
abstract: Globally conserved phase ordering dynamics is investigated in systems with short range correlations at t=0. A Ginzburg-Landau equation with a global conservation law is employed as the phase field model. The conditions are found under which the sharp-interface limit of this equation is reducible to the area-preserving motion by curvature. Numerical simulations show that, for both critical and off-critical quench, the equal-time pair correlation function exhibits dynamic scaling, and the characteristic coarsening length obeys l(t) approximately t(1/2). For the critical quench, our results are in excellent agreement with earlier results. For off-critical quench (Ostwald ripening) we investigate the dynamics of the size distribution function of the minority phase domains. The simulations show that, at large times, this distribution function has a self-similar form with growth exponent 1/2. The scaled distribution, however, strongly differs from the classical Wagner distribution. We attribute this difference to coalescence of domains. A theory of Ostwald ripening is developed that takes into account binary coalescence events. The theoretical scaled distribution function agrees well with that obtained in the simulations.
authors: Dipartimento di Matematica e Fisica, Università di Camerino, and Istituto Nazionale di Fisica della Materia, 62032 Camerino, Italy.
authors: Massimo
authors: M
authors: Conti
authors: Baruch
authors: B
authors: Meerson
authors: Avner
authors: A
authors: Peleg
authors: Pavel V
authors: PV
authors: Sasorov