Researchers have designed novel linear nanomotors that can be moved in controlled directions using laser light. This work opens the way for new microfluidics, including lab-on-a-chip systems with optically actuated pumps and valves.
The scientists have introduced a system of linear motors made from gold nanorods that can move in a controlled direction when exposed to laser light. Like a sailboat that can move in any desired direction by adjusting the rigging, these nanomotors are not constrained to follow the direction of the light. Rather, they move based on their orientation even when exposed to a laser beam traveling from another angle.
The motion is powered by the lateral optical force created from the sideways scattering of laser light from the particles. As a result, the need to focus or shape the laser beam with lenses, which was once a difficult task, is eliminated. In addition, motor sizes are not constrained by the wavelength of light, unlike with previous devices.