We study the Einstein relation between spontaneous fluctuations and the response to an external perturbation for the comb model and the single file, which are examples of systems with sub-diffusive transport properties. The relevance of nonequilibrium conditions is investigated: when a stationary current (in the form of a drift or an energy flux) is present, the Einstein relation breaks down. In the case of the comb model, a general relation - appearing in the recent literature - between the response function and an unperturbed suitable correlation function allows us to explain the obtained results. This suggests that the relevant ingredient in breaking the Einstein formula, for stationary regimes, is not anomalous diffusion but the presence of currents driving the system out of equilibrium. © 2012 The Royal Swedish Academy of Sciences.

The out of equilibrium response function in sub-diffusive systems / G., Gradenigo; A., Puglisi; A., Sarracino; Vulpiani, Angelo; D., Villamaina. - In: PHYSICA SCRIPTA. - ISSN 0031-8949. - 86:5(2012), p. 058516. [10.1088/0031-8949/86/05/058516]

The out of equilibrium response function in sub-diffusive systems

VULPIANI, Angelo;
2012

Abstract

We study the Einstein relation between spontaneous fluctuations and the response to an external perturbation for the comb model and the single file, which are examples of systems with sub-diffusive transport properties. The relevance of nonequilibrium conditions is investigated: when a stationary current (in the form of a drift or an energy flux) is present, the Einstein relation breaks down. In the case of the comb model, a general relation - appearing in the recent literature - between the response function and an unperturbed suitable correlation function allows us to explain the obtained results. This suggests that the relevant ingredient in breaking the Einstein formula, for stationary regimes, is not anomalous diffusion but the presence of currents driving the system out of equilibrium. © 2012 The Royal Swedish Academy of Sciences.
2012
01 Pubblicazione su rivista::01a Articolo in rivista
The out of equilibrium response function in sub-diffusive systems / G., Gradenigo; A., Puglisi; A., Sarracino; Vulpiani, Angelo; D., Villamaina. - In: PHYSICA SCRIPTA. - ISSN 0031-8949. - 86:5(2012), p. 058516. [10.1088/0031-8949/86/05/058516]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/505639
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 6
social impact