Xin-Cheng YAO^* and Dao-Zhong ZHANG¹

Biological and Quantum Physics Group, MS-D454, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
¹Optical Physics Laboratory, Institute of Physics and Center for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China

(Received August 22, 2003; Accepted November 4, 2003)

We report a new, simplified mechanism for performing micro-rotation. A sample chamber filled with aqueous solution and mounted on a piezoelectric transducer (PZT)-driven stage was used to produce flow-induced torque for rotating micro-objects. We demonstrated the scheme by rotating ellipsoidal yeast particles and a two-sphere system with 20 mW of laser power. Clockwise or counterclockwise rotation could be controlled by changing the initial angular position of the object trapped and by reversing the direction of the PZT-driven stage. This mechanism has potential applications in microfabrication, biotechnology and fluidic technology.

Key words: micromanipulator, optical tweezers, optical trapping, micro-rotation, torque

^*To whom correspondence should be addressed. Biological and Quantum Physics Group, MS-D454, Los Alamos National Laboratory, Los Alamos, New Mexico 87545. Email address: xyao@lanl.gov