It has been observed that a nanoparticle can exhibit underdamped motion while moving toward the focal point of an optical trap. It is unclear whether this motion is caused by laser or fluid forces. Dielectrophoretic forces can trap nanoparticles as an alternate approach to optical trapping. The electrical trap uses no laser, so we can determine which force causes the underdamped motion. A microchannel with a quad-electrode arrangement on its ceiling and floor was designed to explore this question. Supplying an oscillating voltage to these electrodes generates an oscillating electric field resulting in the dielectrophoretic force that traps the particle. However, matching common characteristics, such as trap stiffness, is difficult between the two methods. This paper compares the two approaches for a 2 μm diameter particle. Instead of matching the trapping characteristics, the next step in this work is to use the dielectrophoretic device to explore the effect of the particle’s momentum on its motion, which can explain the underdamped motion. Combining optical and dielectrophoretic trapping will offer new insights into the dynamic behavior of small particles in a fluid medium.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.