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Title: Plasmonic-enhanced floating electrode optoelectronic tweezers (FEOET) for effective optical droplet manipulation
A plasmonic-enhanced floating electrode optoelectronic tweezers (FEOET) device is presented for effective optical droplet manipulation. Due to the importance of having a high-quality photoconductive layer, conventional FEOET devices face the issue between ineffective DEP performance and cost-ineffective fabrication. In this study, the use of metallic nanoparticles enables plasmonic light scattering to significantly enhance light absorption onto a photoconductive layer of the device, resulting in a largely improved dielectrophoretic (DEP) performance. Two numerical simulation studies have demonstrated the working principle of plasmonic-enhanced DEP and were further validated experimentally by an improved spectrophotometric light absorbance of the TiOPc layer, as well as demonstrating an 11-fold increase in light-actuated droplet speed. With much-improved DEP performance, this plasmonic-enhanced FEOET technology can provide a low-cost solution for various digital microfluidic (DMF) applications with the benefits of device simplicity.  more » « less
Award ID(s):
2046134
PAR ID:
10397360
Author(s) / Creator(s):
Date Published:
Journal Name:
The 21st International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers 2021)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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