title: Optical trapping of microparticles using silicon nitride waveguide junctions and tapered-waveguide junctions on an optofluidic chip.
abstract: We study optical trapping of microparticles on an optofluidic chip using silicon nitride waveguide junctions and tapered-waveguide junctions. We demonstrate the trapping of single 1 μm-sized polystyrene particles using the evanescent field of waveguide junctions connecting a submicrometer-sized input-waveguide and a micrometer-sized output-waveguide. Particle trapping is localized in the vicinity of the junction. We also demonstrate trapping of one and two 1μm-sized polystyrene particles using tapered-waveguide junctions connecting a submicrometer-sized singlemode input-waveguide and a micrometer-sized multimode output-waveguide. Particle trapping occurs near the taper output end, the taper center and the taper input end, depending on the taper aspect ratio.
authors.affiliation: Photonic Device Laboratory, Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Cai
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Poon
mesh_terms: D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D052898:Optical Tweezers; D055095:Optics and Photonics / Q000295:instrumentation*; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry*
chemical_list: D011137:Polystyrenes; D017655:Silicon Compounds; C032734:silicon nitride