During childhood days we have been to the magic shows and we have always wondered as to how the objects over there fly in the air. Now we know that it wasn’t magic, but it was physics applied that made it look like magic.
Now the researchers at the California Institute of Technology claim that they have found a way to levitate and propel objects using light, even though for time being the work remains theoretical. It is believed according to a paper published in Nature Photonics that this technique could be used for trajectory control of ultra-light spacecraft and even laser propelled light sails for space exploration. It means that no fuel needed, just a powerful laser fired at a spacecraft from the earth.
Scientists developed photonic levitation and propulsion system by designing a complex pattern that could be etched into an object’s surface.
The way the concentrated light beam reflected from the etching causes the object to “self-stabilize“, they say, as it attempts to stay inside the focused laser beam.
The groundwork for the new research was the development of optical tweezers and the big downside to it was that it could manipulate tiny objects at the microscopic level only.
Ognjen Ilic, post-doctoral scholar and first author of the new study, explains the tweezer concept and its limitations in much simpler terms: “One can levitate a ping pong ball using a steady stream of air from a hairdryer. But it wouldn’t work if the ping pong ball were too big, or if it were too far away from the hair dryer, and so on.“
Though the theory is still untested in the real world, the researchers say that if it pans out, it could send a spacecraft to the nearest star outside our Solar System in just 20 years.
“There is an audaciously interesting application to use this technique as a means for propulsion of a new generation of spacecraft,” said Harry Atwater, a professor at the Caltech Division of Engineering and Applied Science.
He also said, “We’re a long way from actually doing that, but we are in the process of testing out the principles.”
Published Research: https://www.nature.com/articles/s41566-019-0373-y