Many of the technological advances we take for granted today got their start as the whimsical creations of toward-thinking sci-fi writers. Star Trek communicators, the spiritual predecessors of our modern mobile phones, allowed the crew of the USS Enterprise to speak to one another with the touch of a button. Star Wars introduced moviegoers to the idea of 3D holograms, a concept that is on the precipice of changing countless industries from retail to healthcare. The Jetsons were the first Zoom users, relying on video calls to stay in touch, while the characters in Fahrenheit 451 wore thimble radios, like today’s wireless earbuds, to stream music and sounds into their brains.
Which innovation will be next to make the leap from our collective imagination to the real world? Will it be replicators, lightsabers, or robot maids? The answer might be tractor beams. I know what you’re thinking. Tractor beams have existed for a while now. Used as optical tweezers, these microscopic beams allow users to move atoms and nanoparticles.
Recently, however, researchers from the QingDao University of Science and Technology in China have successfully created a first-of-its-kind macroscopic tractor beam. This means that the pull of the tractor beam can be viewed with the naked eye. The team documented their findings in a recent paper, “Macroscopic laser pulling based on the Knudsen force in rarefied gas,” which was published in Optics Express.
In an excerpt from the paper, the Chinese team, which consists of Lei Wang, Shige Wang, Qiuling Zhao, and Xia Wang, explains the parameters of their experiment. “The pulling force is originated from the Kundsen force when a gauss laser beam irradiates a macroscopic structure composed of the absorptive bulk cross-linked graphene material and a SiO2 layer. A torsional pendulum device qualitatively presents the laser pulling phenomenon. A gravity pendulum device was used to further measure the pulling force that is more than three orders of magnitudes larger than the radiation pressure.”