We measure the persistence exponent in a phase separating two-dimensional spin system with non-conserved dynamics quenched in a region with four coexisting stripe phases. The system is an Ising model with nearest neighbor, next-to-the-nearest neighbor and plaquette interactions. Due to the particular nature of the ground states, the order parameter is defined in terms of blocks of spins. Our estimate of the persistence exponent, theta = 0.42, differs from those of the two-dimensional Ising and four state Potts models. Our procedure allows the study of persistence properties also at finite temperature T: our results are compatible with the hypothesis that theta does not depend on T below the critical point. (C) 1999 Published by Elsevier Science B.V. All rights reserved.
Persistence exponent in superantiferromagnetic quenching / Cirillo, Emilio Nicola Maria; S., Stramaglia; G., Gonnella. - In: PHYSICA. A. - ISSN 0378-4371. - STAMPA. - 265:1-2(1999), pp. 43-52. [10.1016/s0378-4371(98)00555-x]
Persistence exponent in superantiferromagnetic quenching
CIRILLO, Emilio Nicola Maria;
1999
Abstract
We measure the persistence exponent in a phase separating two-dimensional spin system with non-conserved dynamics quenched in a region with four coexisting stripe phases. The system is an Ising model with nearest neighbor, next-to-the-nearest neighbor and plaquette interactions. Due to the particular nature of the ground states, the order parameter is defined in terms of blocks of spins. Our estimate of the persistence exponent, theta = 0.42, differs from those of the two-dimensional Ising and four state Potts models. Our procedure allows the study of persistence properties also at finite temperature T: our results are compatible with the hypothesis that theta does not depend on T below the critical point. (C) 1999 Published by Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.