Abstract
Rib waveguides are investigated as an alternative to strip waveguides for planar trapping and transport of microparticles. Microparticles are successfully propelled along the surface of rib waveguides and trapped in the gap between opposing rib waveguides. The trapping capabilities of waveguide end facets formed by a single and opposing waveguide geometries are investigated. The slab beneath a rib waveguide continues to guide light after the end facet of a rib waveguide. Thus particles can be trapped in wider gaps formed by opposing rib waveguides than with strip waveguides. Rib waveguides were found more efficient in trapping a collection of particles in the gap and particles could be moved to different locations in the gap by changing the relative power in the two opposing rib waveguides. Numerical simulations are used to show that the trapping efficiency on the surface of rib and strip waveguides is comparable. The simulations also confirm the advantage of opposing rib waveguides for trapping particles in wide gaps. The low sidewalls of rib waveguides give low propagation losses and make it easy to integrate rib waveguides with other functions in a lab-on-a-chip where particle trapping and transport is required.
Highlights
Optical trapping has found a number of applications in biology and nanotechnology [1,2]
In this paper, we show that rib waveguides provide an alternative design option for optical trapping and transport of particles
It was found that the power in the evanescent field of a rib waveguide is almost identical to that of a strip waveguide for the parameters used here
Summary
Optical trapping has found a number of applications in biology and nanotechnology [1,2]. It has been shown that this evanescent field can successfully trap and propel a range of particle types (polystyrene spheres, nanowires, cells, virus) and sizes [3,4,5,6,7,8,9,10,11,12,13,14]. Narrow rib waveguides have significantly lower propagation losses than strip waveguides due to the lower side-walls [15]. A systematic study of rib waveguides for planar waveguide trapping, and in comparison with strip waveguides, is presented. The lower propagation losses can make it possible to propel particles over longer distances and use optical trapping in larger labon-a-chip systems
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
