Controlled trapping and rotation of carbon nanotube bundle with optical tweezers

Controlled optical trapping and rotation of carbon nanotube bundle (CNTB) including single-walled and multi-walled carbon nanotube in aqueous solution, were performed using the optical tweezers. Vertical and horizontal trapping of CNTB was performed depending on the size of CNTB and the trapping depth. In addition, four different rotations of the trapped CNTB were described and explained by the interaction between CNTB and the laser field, and the convection of the aqueous solution induced by thermalphoresis effect. These results will pave the way to assemble some CNTs-based devices such as micro motors.