Laser-induced thermocapillary convection for mesoscale manipulation

Modulation of surface stresses is a recent and promising method to perform mesoscale manipulation of components in liquid medium. We present a promising approach using infra red laser-induced thermocapillary-driven flow for handling multiple or single large and heavy objects. The objects are immersed in thin liquid layers and in contact with the substrate surface. These objects can be handled with high speed thermocapillary convection flow reaching significant forces depending on the object sizes. Velocity measurements showed that 92-μm-sized spherical beads can be dragged with velocities of about 5.5-mm/s. Parallel non-contact micromanipulation can be achieved.