Prof. Charles Baroud, Ecole Polytechnique, Palaiseau

Since surface forces become dominant over volumetric forces in microfluidics, manipulating surface tension is a promising way to control the motion of droplets. I will describe an opto-thermal technique that we have developed which allows for the production of large forces, with no special fabrication and without mechanical moving parts. In addition to discussing the theoretical aspects related to thermocapillarity and droplet transport, I will show several examples of how localized heating from a laser can be used to provide total control of droplet microfluidics. Finally, holographic methods can extend the technique to complex manipulations of multiple drops in parallel.