Europhys. Lett, 43 (5), pp. 552-557 (1998)

Phase separation in systems with absorbing states

M. A. Muñoz ¹, U. Marini Bettolo Marconi ^1,2 and R. Cafiero ^1,3

¹ INFM Sezione di Roma 1, and Dipartimento di Fisica
Università di Roma "La Sapienza'' - Piazzale A. Moro 2, I-00185 Roma, Italy
² INFM Sezione di Camerino and Dipartimento di Matematica e Fisica
Università di Camerino - Via Madonna delle Carceri, I-62032, Camerino, Italy
³ Max-Planck Institut für Physik komplexer Systeme
Nöthnitzer Strasse 38, D-01187 Dresden, Germany

(received 10 March 1998; accepted in final form 8 July 1998)

PACS. 64.60 - General studies of phase transitions.
PACS. 64.60Cn - Order-disorder transformations; statistical mechanics of model systems.

Abstract:

We study the problem of phase separation in systems with a positive definite order parameter, and in particular, in systems with absorbing states. Owing to the presence of a single minimum in the free energy driving the relaxation kinetics, there are some basic properties differing from standard phase separation. We study this class of systems analytically and numerically; in particular we determine the phase diagram, the growth laws in one and two dimensions and the presence of scale invariance. Some applications are also discussed.

***