SORTING OF BROWNIAN PARTICLES BY THE PULSED APPLICATION OF AN ASYMMETRIC POTENTIAL

Citation
L. Gorretalini et al., SORTING OF BROWNIAN PARTICLES BY THE PULSED APPLICATION OF AN ASYMMETRIC POTENTIAL, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 56(2), 1997, pp. 2025-2034
Citations number
23
Categorie Soggetti
Physycs, Mathematical","Phsycs, Fluid & Plasmas
ISSN journal
1063651X
Volume
56
Issue
2
Year of publication
1997
Pages
2025 - 2034
Database
ISI
SICI code
1063-651X(1997)56:2<2025:SOBPBT>2.0.ZU;2-N
Abstract
We submit a suspension of Brownian latex spheres in water to a spatial ly periodic and asymmetric potential successively switched on and off. Such a potential is created by dielectrophoretically induced forces r esulting from the application of a high-frequency electric field betwe en a plane electrode and a blazed optical grating. As expected, we obs erve a net macroscopic drift of the particles. Their average velocitie s have been measured as a function of the time during which the field is switched off. We observe a quantitative agreement with the theoreti cal predictions. In particular, the velocities strongly differ accordi ng to the size of the latex spheres, which should open the way to devi ces aimed at the separation of micrometer and submicrometer particles. The geometry of the gratings as well as the concentration and the sur face functions of the particles has also been investigated.