
Researchers have designed a way to levitate and propel objects using only light by creating specific nanoscale patterning on the objects' surfaces. The work could be a step toward developing a spacecraft that could reach the nearest planet outside of our solar system in 20 years, powered and accelerated only by light.
Decades ago, the development of optical tweezers enabled scientists to move and manipulate tiny objects, like nanoparticles, using the radiative pressure from a sharply focused beam of laser light; however, optical tweezers are only able to manipulate very small objects and only at very short distances.
With the new technology, objects of many different shapes and sizes — from micrometers to meters — could be manipulated with a light beam. The key is to create specific nanoscale patterns on an object's surface. This patterning interacts with light in such a way that the object can right itself when perturbed, creating a restoring torque to keep it in the light beam. Thus, rather than requiring highly focused laser beams, the objects' patterning is designed to "encode" their own stability. The light source can also be millions of miles away.
In theory, a spacecraft could be patterned with nanoscale structures and accelerated by an Earth-based laser light. Without needing to carry fuel, the spacecraft could reach very high or even relativistic speeds and possibly travel to other stars.
For more information, contact Lori Dajose