Non-contact mesoscale manipulation using laser induced convection flows

Laser induced convection flows is a new and promising method to achieve better manipulation of mesoscale objects (above 1 mum and below 500 mum) in a liquid medium. The temperature gradient created by laser absorption generates natural and thermocapillary (or Marangoni) convection flows. These flows are used to perform the manipulation itself. In this paper, we demonstrate for the first time that large and heavy particles can be dragged using the Marangoni convection flows. Experiments based on these phenomena show that fast and accurate underwater micromanipulation of particles up to 280 mum is possible using only a convergent 1480 nm laser beam.