Scientists turn light into a tractor beamSubmitted by Bob-45 on Tue, 01/29/2013 - 14:01
By David Szondy
January 28, 2013
From The Skylark of Space to Star Wars, no self-respecting science fiction spaceship would break orbit without a tractor beam on board. We’re still a long way from locking on to errant shuttlecraft, but a team led by Dr. Tomas Cizmar, Research Fellow in the School of Medicine at the University of St. Andrews, Scotland, has turned a laser into a tractor beam that works on the microscopic level.
Tractor beams are one of those things that seem on the far edge of what’s possible. The idea of a beam of energy streaming out that pulls things in is counter-intuitive, but scientists have been developing things that work like tractor beams since the 1960s and light manipulation has been tried since the 1970s.
In recent years, several ways of imitating the fictional tractor beam have been investigated, including optical vortices, optical tweezers, Bessel beams and optical pipelines. Developed in association with the Institute of Scientific Instruments (ISI) in the Czech Republic, the St. Andrews team claims that its tractor beam is different in that it’s the first time that a light beam has been made to draw objects toward the light source.