swedish scientists have achieved a groundbreaking result by developing the world's smallest light-driven motor. this achievement paves the way for the development of micro-machines that can operate inside the human body and function as pumps and valves.
researchers from the university of gothenburg have overcome a fundamental obstacle in micro-engineering by abandoning conventional mechanical transmission methods. instead, they have adopted photonic metamaterials, a special structure that can capture and manipulate light at the nanoscale.
the gear itself, which is just a few dozen micrometers in diameter (smaller than a human hair), is manufactured from silicon using photolithography. when a laser is shone on the gear's metamaterial, the gear starts to rotate. the speed of the gear is controlled by the intensity of the light, and its direction is controlled by changing the polarization of the light.
according to lead author guang wang, they have developed a system in which a single light-driven gear can drive an entire circuit. this system can convert rotational motion into linear motion. integrated directly into microchips and controlled by light, this technology paves the way for the creation of complex micro-systems.