Volume 76, Number 6, December 2006
|Page(s)||1022 - 1028|
|Published online||16 November 2006|
Violation of the fluctuation-dissipation theorem in confined driven colloids
Dipartimento di Ingegneria Chimica, DICCISM, Università di Pisa I-56126 Pisa, Italy
2 Dipartimento di Fisica “Enrico Fermi”, Università di Pisa Largo B. Pontecorvo 3, I-56127 Pisa, Italy
3 SOFT-INFM-CNR - P.zza A. Moro 2, I-00185, Roma, Italy
Accepted: 20 October 2006
Analytical models describing a colloidal particle confined in a harmonic well, e.g. provided by an optical trap, and driven by shear flows are presented. Violation of both static and dynamic fluctuation-dissipation theorem (FDT) is clearly seen, thus clarifying the connection between such FDT violation and the breakdown of the detailed balance. The simple shear and Taylor-Couette velocity fields are studied in detail, showing that loosening confinement enhances FDT violations. In addition, cases violating FDT but not energy equipartition are presented. For the cases under study, an effective temperature is defined via the static FDT, which appears to be more physically sound than the one defined via the time-dependent FDT. Confining sheared colloidal particles by optical tweezers yields considerable FDT violation.
PACS: 05.40.-a – Fluctuation phenomena, random processes, noise, and Brownian motion
© EDP Sciences, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.