Original URL: http://www.theregister.co.uk/2011/11/02/nasa_funding_tractor_beam_research/

NASA funds laser tractor beam research

Shifting particles, not the Enterprise, using SciFi staple

By Iain Thomson

Posted in Science, 2nd November 2011 05:00 GMT

NASA has awarded a $100,000 grant to three boffins who are investigating a tractor beam trifecta.

Principal Investigator Paul Stysley and team members Demetrios Poulios and Barry Coyle at NASA's Goddard Space Flight Center received the grant to research three methods of using lasers to collect particulate samples without the need for touch, which could contaminate the collected material.

"Though a mainstay in science fiction, and Star Trek in particular, laser-based trapping isn't fanciful or beyond current technological know-how," Stysley said in a statement. "The original thought was that we could use tractor beams for cleaning up orbital debris, but to pull something that huge would be almost impossible - at least now. That's when it bubbled up that perhaps we could use the same approach for sample collection."

One of the methods under study uses "optical tweezers" – two counter-propagating beams of light. This is already in use in a limited way and adjusts the strength of the two beams to move particles within the ring-like structure created by the beams, via the heat that those beams generates. While promising, this technique does require an atmosphere in which to work, making it unsuitable for many missions.

The second technique, which has been tested in the laboratory, uses optical solenoid beams – which the boffins define as "those whose intensity peaks spiral around the axis of propagation" – to pull particles towards the light source using electromagnetic effects. This technique will work in a vacuum, making it suitable for deep space missions.

The third technique is entirely theoretical at this point, but uses Bessel beams to induce electrical or magnetic fields within particulates, and use those to propel them.

"We want to make sure we thoroughly understand these methods," Coyle said. "We have hope that one of these will work for our purposes. We're at the starting gate on this. This is a new application that no one has claimed yet." ®