Optical "snowblowing" of microparticles and cells in a microfluidc environment using Airy and parabolic wavepackets

Abstract

ABSTRACT The year 2007 witnessed the experimental realization of extraordinary laser beams termed Airy and parabolicbeams. Surprisingly, these b eams are immune to diraction and in additi on exhibit transverse acceleration whilepropagating. This peculiar property of both Airy and para bolic beams facilitates the clearance of both micropar-ticles and cells from a region in a sample chamber through particle/cell transport along curved trajectories. Weterm this concept Optically mediated particle clearingŽ (OMPC) and, alternatively, Optical redistributionŽ(OR) in the presence of a micro”uidic environment, where particles and cells are propelled over micrometer-sized walls. Intuitively, Airy and parabolic beams act as a form of micrometer-sized snowblowerŽ attractingmicroparticles or cells at the bottom of a sample chamber to blow them in an arc to another region of the sample.In this work, we discuss the performance and limitations of OMPC and OR which are currently based on a singleAiry beam optionally fed by a single parabolic beam. A possible strategy to massively enhance the performanceof OMPC and OR is based on large arrays of Airy beams. We demonstrate the “rst experimental realization ofsuch arrays.Keywords: Airy beam, parabolic beam, particle clearing, optical trapping, optical guiding, spatial light mod-ulator, colloid, cell, micro”uidics