Page 94 - Optofluidics Fundamentals, Devices, and Applications

CHAPTER 5

Optofluidic Trapping

and Transport Using

Planar Photonic

Devices

David Erickson
Sibley School of Mechanical and Aerospace Engineering, Cornell University,
Ithaca, New York
Allen H. J. Yang
Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York

Extended Abstract
In this chapter we introduce the concept of “optofluidic transport,”
which is shown conceptually in Fig. 5-1.
We review the use of near-field optical forces in the evanescent
field of a waveguide to perform transport operations in lab-on-chip
devices. Briefly, the near-field optical gradients (which serve to confine
particles through a Lorenz force, F ) and concentrated optical energy
trap
(resulting in intense scattering and absorption forces for propulsion,
F ) in these devices can be used to perform a series of particle-
prop
handling operations including transport and separation. The focus of
this chapter is on describing the physics behind this form of transport
and some of the potential advantages over the state of the art.
This represents a new method of performing optical transport in
lab-on-chip devices, relying on the intense electromagnetic energy in

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