title: Operational Regimes and Physics Present in Optoelectronic Tweezers.
abstract: Optoelectronic tweezers (OET) are a powerful light-based technique for the manipulation of micro- and nanoscopic particles. In addition to an optically patterned dielectrophoresis (DEP) force, other light-induced electrokinetic and thermal effects occur in the OET device. In this paper, we present a comprehensive theoretical and experimental investigation of various fluidic, optical, and electrical effects present during OET operation. These effects include DEP, light-induced ac electroosmosis, electrothermal flow, and buoyancy-driven flow. We present finite-element modeling of these effects to establish the dominant mode for a given set of device parameters and bias conditions. These results are confirmed experimentally and present a comprehensive outline of the operational regimes of the OET device.
authors.affiliation: The authors are with the Electrical Engineering and Computer Science Department, Berkeley Sensor and Actuator Center, University of California, Berkeley, CA 94720 USA.
authors.forename: Justin K
authors.initials: JK
authors.lastname: Valley
authors.forename: Arash
authors.initials: A
authors.lastname: Jamshidi
authors.forename: Aaron T
authors.initials: AT
authors.lastname: Ohta
authors.forename: Hsan-Yin
authors.initials: HY
authors.lastname: Hsu
authors.forename: Ming C
authors.initials: MC
authors.lastname: Wu