Scientists create real-life tractor beam (but there's a catch)

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Jan 25, 2013

We haven't made first contact with the Vulcans yet, but science just got us a little closer to living in Star Trek.

A research team including scientists from the University of St. Andrews and the Czech Republic's Institute of Scientific Instruments (ISI) just announced that they have indeed developed a beam of light that will pull objects toward the light source. It's a real tractor beam, and apparently it works very well, but the catch is that it only works with very, very tiny objects.

Though the beam only works when it's pulling something microscopic, the team behind the invention did manage to solve one of the key problems with developing tractor beam technology. Light's usual reaction when coming into contact with objects is to push against them. It's called "radiation force," and it was first discovered by the legendary astronomer Johannes Kepler, who noticed that the tails of comets point away from the sun. We don't feel it because we're too big, but when a beam of light hits something microscopic, it actually pushes the object backward, if only a little.

Recent research suggested that there were certain conditions under which this radiation force would reverse, pulling an object rather than pushing it. Now this team of researchers, led by St. Andrews' Tomas Cizmar and ISI's Oto Brzobohaty and Pavel Zemanek, has managed to put that theory into practice, enacting a "negative" radiation force that pulls microscopic objects.

We sci-fi fans might be wishing the beam could pull something bigger, like, say, a Romulan Bird of Prey, but this is more than just the first step to a bigger tractor beam. A device that can pull microscopic objects in toward a light source could be very useful if applied to medical testing. Think of how much easier it would be to examine blood cells up close if you could just pull them in with light. What's more, the team has also discovered that different objects react to the beam in different ways, which means it could be used to tell microscopic objects apart (like cancerous and non-cancerous cells, perhaps). The team even hopes the technology will have uses outside of the field of light manipulation.

"Because of the similarities between optical and acoustic particle manipulation we anticipate that this concept will provide inspiration for exciting future studies in areas outside the field of photonics," Cizmar said.

So, science just made a big stride in the development of the tractor beam. Next: the Holodeck!

(Via Phys.Org)