Issue
EPL
Volume 81, Number 6, March 2008
Article Number 60004
Number of page(s) 6
Section General
DOI http://dx.doi.org/10.1209/0295-5075/81/60004
Published online 22 February 2008
EPL, 81 (2008) 60004
DOI: 10.1209/0295-5075/81/60004

Residence and waiting times of Brownian interface fluctuations

V. W. A. de Villeneuve1, J. M. J. van Leeuwen2, J. W. J. de Folter1, D. G. A. L. Aarts3, W. van Saarloos2 and H. N. W. Lekkerkerker1

1  Van 't Hoff Laboratory for Physical and Colloid Chemistry, University of Utrecht - Padualaan 8, 3584 CH Utrecht, The Netherlands
2  Instituut-Lorentz for Theoretical Physics, Leiden University - Niels Bohrweg 2, Leiden, 2333 CA, The Netherlands
3  Physical and Theoretical Chemistry Laboratory, University of Oxford - South Parks Road, Oxford OX1 3QZ, UK


received 12 October 2007; accepted in final form 22 January 2008; published March 2008
published online 22 February 2008

Abstract
We report on the residence times of capillary waves above a given height h and on the typical waiting time in between such fluctuations. The measurements were made on phase-separated colloid-polymer systems by laser scanning confocal microscopy. Due to the Brownian character of the process, the stochastics vary with the chosen measurement interval $\Delta t$. In experiments, the discrete scanning times are a practical cutoff and we are able to measure the waiting time as a function of this cutoff. The measurement interval dependence of the observed waiting and residence times turns out to be solely determined by the time-dependent height-height correlation function g(t). We find excellent agreement with the theory presented here along with the experiments.

PACS
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
68.03.Kn - Dynamics (capillary waves).
82.70.Dd - Colloids.

© EPLA 2008