Electrokinetic patterning of colloidal particles with optical landscapes

We demonstrate an opto-electrokinetic technique for noninvasive particle manipulation on the surface of a parallel-plate indium tin oxide (ITO) electrode that is biased with an alternating current (AC) signal and illuminated with near-infrared (1064 nm) optical landscapes. This technique can generate strong microfluidic vortices at higher AC frequencies (\u3e 100 kHz) and dynamically and rapidly aggregate and pattern particle groups at low frequencies (\u3c 100 kHz)