title: Induced-charge electroosmotic trapping of particles.
abstract: Position-controllable trapping of particles on the surface of a bipolar metal strip by induced-charge electroosmotic (ICEO) flow is presented herein. We demonstrate a nonlinear ICEO slip profile on the electrode surface accounting for stable particle trapping behaviors above the double-layer relaxation frequency, while no trapping occurs in the DC limit as a result of a strong upward fluidic drag induced by a linear ICEO slip profile. By extending an AC-flow field effect transistor from the DC limit to the AC field, we reveal that fixed-potential ICEO exceeding RC charging frequency can adjust the particle trapping position flexibly by generating controllable symmetry breaking in a vortex flow pattern. Our results open up new opportunities to manipulate microscopic objects in modern microfluidic systems by using ICEO.
authors.affiliation: School of Mechatronics Engineering, Harbin Institute of Technology, West Da-zhi Street 92, Harbin, Heilongjiang, PR China 150001. rykhit@hit.edu.cn.
authors.forename: Yukun
authors.initials: Y
authors.lastname: Ren
authors.forename: Weiyu
authors.initials: W
authors.lastname: Liu
authors.forename: Yankai
authors.initials: Y
authors.lastname: Jia
authors.forename: Ye
authors.initials: Y
authors.lastname: Tao
authors.forename: Jinyou
authors.initials: J
authors.lastname: Shao
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Ding
authors.forename: Hongyuan
authors.initials: H
authors.lastname: Jiang