Scientists are one step closer to creating a working tractor beam
Australian laser physicists have created a new hollow laser beam capable of retracting and repulsing certain particles. It’s not quite at the level of what the Enterprise in Star Trek is packing, but it’s a start.
Based on a paper originally published in Nature Photonics and caught by the Australian website Science Alert, the new laser emits a beam that is bright around the edges and hollow in the center. In other words, it kind of looks like the tractor beams in Star Trek.
The laser was designed to affect gold-coated glass particles that become trapped in the hollow center. The way it works is that the laser interacts with the particles, creating hot spots. When the air collides with those hotspots, it pushes the particles away. In what is very much a Star Trek-like piece of techno babble, reversing the polarity of the laser (no, really), creates hotspots on the other side of the particles and draws them in.
Of course, influencing tiny particles is a far cry from grabbing another spaceship and dragging it along. Plus, the lack of air in space creates a bit of an issue since it is air particles that moves the particles, but it is still a major accomplishment.
The researchers were able to move the particles up to 20 centimeters, but according to the team the laser could work over several meters. The size of the lab was the only thing limiting the distance.
Although a tractor beam in the traditional sci-fi sense is still a long, long way off, there are practical considerations for the laser that are much closer to reality. The laser was built to interact with one specific type of particle, but it could conceivably work on several types of particles.
One possible application is that the laser could – in theory – be used to isolate harmful particles in the atmosphere, and then attract them to point where they can be collected and removed or just pushed out of the way. That too is a long way off, but the potential is there.