Optically mediated particle clearing using Airy wavepackets

The Airy wavepacket solution for a free particle exhibits propagation invariance and, surprisingly, acceleration transverse to the propagation direction(1). Discovered as a solution of the free-particle Schrodinger equation, Airy wavepackets have been predicted(2), and in a recent major step forward, realized(3) in the optical domain, but have never been used in any application. In this Letter we demonstrate the first use of the Airy light beam in optical micromanipulation(4,5). Based on the characteristic intensity pattern, the beam drags particles into the main intensity maximum, which guides particles vertically along a parabolic trajectory. This unusual property of Airy beams leads to a new feature in optical micromanipulation-the removal of particles and cells from a section of a sample chamber. We term this highly robust and efficient process 'optically mediated particle clearing', which enables novel microfluidic applications within the colloidal and biological sciences.