Scientists at CalTech have developed a method to levitate and move objects utilizing just light, by producing particular nanoscale pattern on the objects’ surface areas.
(The cover image is a conceptual illustration of a nano-patterned item reorienting itself to stay in a beam. Credit: Atwater Labs)
Though still theoretical, the work is an action towards establishing a spacecraft that might reach the nearby world beyond our planetary system in 20 years, powered and sped up just by light.
A paper explaining the research appears online in the March 18 edition of the journal Nature Photonics. The research was performed in the lab of Harry Atwater, Howard Hughes Teacher of Applied Physics and Products Science in Caltech’s Department of Engineering and Applied Science.
Years ago, the advancement of so-called optical tweezers allowed researchers to move and control small objects, like nanoparticles, utilizing the radiative pressure from a greatly focused beam of laser light. This work formed the basis for the 2018 Nobel Reward in Physics. Nevertheless, optical tweezers are just able to control extremely little objects and just at extremely brief ranges.
Ognjen Ilic, postdoctoral scholar and the research study’s very first author, offers an example: “One can levitate a ping pong ball using a steady stream of air from a hair dryer. 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.”
With this brand-new research, objects of several shapes and sizes—from micrometers to meters—might be controlled with a beam. The secret is to produce particular nanoscale patterns on a things’s surface area. This pattern connects with light in such a method that the item can right itself when perturbed, producing a restoring torque to keep it in the beam. Hence, instead of needing extremely focused laser beams, the objects’ pattern is developed to “encode” their own stability. The source of light can likewise be countless miles away.
“We have come up with a method that could levitate macroscopic objects,” states Atwater, who is likewise the director of the Joint Center for Artificial Photosynthesis. “There is an audaciously interesting application to use this technique as a means for propulsion of a new generation of spacecraft. We’re a long way from actually doing that, but we are in the process of testing out the principles.”
In theory, this spacecraft might be patterned with nanoscale structures and sped up by an Earth-based laser light. Without requiring to bring fuel, the spacecraft might reach extremely high, even relativistic speeds and potentially take a trip to other stars.
Atwater likewise pictures that the technology might be utilized here in the world to make it possible for quick production of ever-smaller sized objects, like circuit boards.
The paper is entitled “Self-stabilizing photonic levitation and propulsion of nanostructured macroscopic objects.” Financing was supplied by the Airforce Office of Scientific Research.