Ergodicity of a Single Particle Confined in a Nanopore

Stefano Bernardi, J. S. Hansen, Federico Frascoli, B. D. Todd, Carl P. Dettmann

Research output: Contribution to journalEditorial (Academic Journal)peer-review

1 Citation (Scopus)

Abstract

We analyze the dynamics of a gas particle moving through a nanopore of adjustable width with particular emphasis on ergodicity. We give a measure of the portion of phase space that is characterized by quasiperiodic trajectories which break ergodicity. The interactions between particle and wall atoms are mediated by a Lennard-Jones potential, so that an analytical treatment of the dynamics is not feasible, but making the system more physically realistic. In view of recent studies, which proved non-ergodicity for systems with scatterers interacting via smooth potentials, we find that the non-ergodic component of the phase space for energy levels typical of experiments, is surprisingly small, i.e. we conclude that the ergodic hypothesis is a reasonable approximation even for a single particle trapped in a nanopore. Due to the numerical scope of this work, our focus will be the onset of ergodic behavior which is evident on time scales accessible to simulations and experimental observations rather than ergodicity in the infinite time limit.

Original languageEnglish
Pages (from-to)1156-1169
Number of pages14
JournalJournal of Statistical Physics
Volume148
Issue number6
DOIs
Publication statusPublished - Sep 2012

Cite this