Posts Tagged ‘tractor beams’
In Two New Breakthroughs, Scientists Capture Individual Atoms
Scientists led by Mikkel F. Andersen at the University of Otago in New Zealand used lasers to slow down the frenetic movement of a group of rubidium-85 atoms, and then capture them inside optical tweezers. The method could catch and isolate atoms 83 percent of the time. Using the — really two lasers acting as a kind of tractor beam — Andersen’s team was able to hold a single rubidium atom in front of a camera designed for use in space, and snap its picture.
The process could simplify the process of building quantum-logic computers, which use small groups of atoms as information processors. Unlike binary computers, quantum processors could perform many difficult calculations at once, crunching data much more quickly. They could also that would otherwise be too hard to hack.
Andersen said his method would allow computer engineers to grasp 10 or so atoms at a time. The next step is to entangle the atoms so they can share information, he said.
Meanwhile, last Friday, IBM researchers published a study in the journal Science that also used advanced imaging to record individual atoms. Their measurements could help scientists see an atom’s electronic and magnetic properties, and it could help them engineer the spin of individual atoms to create .
IBM’s study used a scanning tunneling microscope to watch the behavior of individual iron atoms at a speed about a million times faster than previously possible. It worked like a high-speed camera freezing the motion of a hummingbird’s wings, as .
Typically, scanning tunneling microscopes work relatively slowly, so scientists can’t watch atomic action in real time. But the new technique let them capture atomic motion to study atoms’ magnetic orientation. They found the speed at which atoms change their magnetic orientation depends on the magnetic field they’re in. This could help scientists engineer atoms’ magnetic lifetime, according to IBM.
Learn more about it in this video.
Working Tractor Beam Can Move Objects 5 Feet With Just Light
Using only light, Australian researchers say they are able to almost five feet through the air. It’s more than 100 times the distance achieved by existing optical “tweezers,” the researchers say.
Not quite a simple grabby tractor beam, the new system works by shining a hollow laser beam at an object and taking advantage of air-temperature differences to move it around.
Moving objects with powerful light is not new — researchers have long been using optical tweezers to pluck bacteria-sized particles and move them a few millimeters. The U.S. Secretary of Energy, Steven Chu, won his Nobel Prize for work with optical tweezers. But Andrei Rhode and colleagues at the Australian National University say their new laser device can move glass objects hundreds of times bigger than bacteria, and shove them a meter and a half (5 feet) or more. Rhode says the 1.5-meter limit was only because of the size of the table where he placed his lasers — he thinks he can move objects up to 10 meters, or about 30 feet.
It works by shining a hollow laser beam around small glass particles, as Inside Science explains. The air around the particle heats up, but the hollow center of the beam stays cool. The heated air molecules keep the object balanced in the dark center. But a small amount of light sneaks into the hollow, warming the air on one side of the object and nudging it along the length of the laser beam. Researchers can change the speed and direction of the glass object by changing the lasers’ brightness.
The system needs heated air or gas to work, so in its present incarnation it wouldn’t work in space — sorry, Star Wars fans. But it could be used for a variety of purposes on Earth, like biological research or movement of hazardous materials.
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