The integrated response function in phase-ordering systems with scalar, vector, conserved, and nonconserved order parameter is studied at various space dimensionalities. Assuming scaling of the aging contribution ?ag(t,tw)=tw-a???(t/tw) we obtain, by numerical simulations and analytical arguments, the phenomenological formula describing the dimensionality dependence of a? in all cases considered. The primary result is that a? vanishes continuously as d approaches the lower critical dimensionality dL. This implies that (i) the existence of a nontrivial fluctuation dissipation relation and (ii) the failure of the connection between statics and dynamics are generic features of phase ordering at dL.
Generic features of the fluctuation dissipation relation in coarsening systems
Claudio Castellano;
2004
Abstract
The integrated response function in phase-ordering systems with scalar, vector, conserved, and nonconserved order parameter is studied at various space dimensionalities. Assuming scaling of the aging contribution ?ag(t,tw)=tw-a???(t/tw) we obtain, by numerical simulations and analytical arguments, the phenomenological formula describing the dimensionality dependence of a? in all cases considered. The primary result is that a? vanishes continuously as d approaches the lower critical dimensionality dL. This implies that (i) the existence of a nontrivial fluctuation dissipation relation and (ii) the failure of the connection between statics and dynamics are generic features of phase ordering at dL.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.