Physicists from ITMO University developed a model of an optical tractor beam to capture particles based on new artificial materials. Such a beam is capable of moving particles or cells towards the radiation source. The study showed that hyperbolic metasurfaces are promising for experiments on creating the tractor beam, as well as for its practical applications. The results are published in ACS Photonics.
The tractor beams are familiar to many thanks to the Star Wars, Star Trek series and countless pictures of a UFO kidnaping a cow. Yet scientists are trying to obtain such beams in reality, and there are already several ways to make objects move towards a source of light. So far, however, these objects are represented by small particles and atoms instead of whole cows.
Researchers from ITMO University recently suggested using metamaterials to create such tractor beams. Metamaterials are artificial periodic structures with unusual optical properties consisting of repetitive elements. For instance, metamaterials can support hyperbolic modes: special states of the electromagnetic field arising when the metamaterial interacts with light. Such states help to control the optical forces that influence objects on the material surface, and, as it turns out, can help to move particles towards the light source.To read more, click here.