Tractor beams have been a science fiction staple since we began our imaginary explorations into space, but it seems that scientists at the Australian National University have made a breakthrough that will bring them out of dreamland.
Tractor beam-like technologies have existed since the late 1980s in the form of optical tweezers, but these have only applied on the micro scale, moving bacteria and organizing cells. The larger version demonstrated by the university is able to move particles of glass that are orders of magnitude larger than bacteria across a distance of over a meter.
The hands-free feat is accomplished through the use of a hollow laser beam. The outer layer of the beam heats the surrounding air, while the center remains cool. The particle travels through the core of the beam, and is nudged back into place by the heated air particles if it drifts out of the cooler center column. By shining a laser in the opposite direction and varying the intensity, the particle can be guided from one end of the beam to the other.
Because it relies on variances in temperature of air molecules, we can’t expect to see this research lead to a beam that’ll function in the vacuum of outer space, but the scale and distance could potentially grow here on Earth, and Andrei Rode of the Australian National University research team tells Inside Science, “With the particles and the laser we use, I would guess up to 10 meters in air should not be a problem. The max distance we had was 1.5 meters, which was limited by the size of the optical table in the lab.”
With more advanced tractor beam technology, things like dangerous or hazardous materials could be transported safely for biomedical research. In the future, maybe we’ll see even larger objects travel weightlessly across long distances (imagine a ‘pass the salt laser gun?’). Ok, so maybe we’re a few decades ahead of intergalactic domination via tractor beam control, but come on! That thing is floating! On a laser!
What do you think… where else should this emerging technique be used?
via Inside Science