The persistence of ratchet effects, i.e., nonzero mass flux under a zero-mean time-dependent drive, when many-body interactions are present, is studied via molecular dynamics (MD) simulations of a simple liquid flowing in an asymmetric nanopore. The results show that (i) ratchet effects persist under many-body density correlations induced by the forcing; (ii) two distinct linear responses (flux proportional to the drive amplitude) appear under strong loads. One regime has the same conductivity of linear response theory up to a forcing of about 10 kT, while the second displays a smaller conductivity, the difference in responses is due to geometric effects alone. (iii) Langevin simulations based on a naive mapping of the many-body equilibrium bulk diffusivity, D, onto the damping rate, gamma are also found to yield two distinct linear responses. However, in both regimes, the flux is significantly smaller than the one of MD simulations.

Molecular dynamics simulation of ratchet motion in an asymmetric nanochannel / Chinappi M.; De Angelis E.; Melchionna S.; Casciola C.M.; Succi S.; Piva R.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - ELETTRONICO. - 97:(2006). [10.1103/PhysRevLett.97.144509]

Molecular dynamics simulation of ratchet motion in an asymmetric nanochannel

DE ANGELIS, ELISABETTA;
2006

Abstract

The persistence of ratchet effects, i.e., nonzero mass flux under a zero-mean time-dependent drive, when many-body interactions are present, is studied via molecular dynamics (MD) simulations of a simple liquid flowing in an asymmetric nanopore. The results show that (i) ratchet effects persist under many-body density correlations induced by the forcing; (ii) two distinct linear responses (flux proportional to the drive amplitude) appear under strong loads. One regime has the same conductivity of linear response theory up to a forcing of about 10 kT, while the second displays a smaller conductivity, the difference in responses is due to geometric effects alone. (iii) Langevin simulations based on a naive mapping of the many-body equilibrium bulk diffusivity, D, onto the damping rate, gamma are also found to yield two distinct linear responses. However, in both regimes, the flux is significantly smaller than the one of MD simulations.
2006
Molecular dynamics simulation of ratchet motion in an asymmetric nanochannel / Chinappi M.; De Angelis E.; Melchionna S.; Casciola C.M.; Succi S.; Piva R.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - ELETTRONICO. - 97:(2006). [10.1103/PhysRevLett.97.144509]
Chinappi M.; De Angelis E.; Melchionna S.; Casciola C.M.; Succi S.; Piva R.
File in questo prodotto:
Eventuali allegati, non sono esposti

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/11585/31952
 Attenzione

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

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 32
  • ???jsp.display-item.citation.isi??? 29
social impact