By Andrew Nusca
Posting in Technology
Scientists have long debated if gasses could display the same magnetic properties as solids. With a little help from lasers, a team of researchers has proven it to be true.
With a little help from lasers, a team of researchers has proven it to be true.
MIT researchers observed magnetism in lithium gas cooled down to 150 millionths of a degree above absolute zero. By training an infrared laser beam on the gaseous cloud -- the primary method physicists use to lower gas temperatures to near absolute zero -- the scientists were able to stun the atoms, slowing them down and lowering their temperature.
By increasing the repulsive forces between the atoms, the researchers observed several features indicating that the gas had become ferromagnetic: the cloud first became bigger and then suddenly shrunk; and once the atoms were released from the trap, it suddenly expanded again.
The research is part of an MIT program studying novel magnetic materials — which have important applications in data storage, nanotechnology and medical diagnostics — and the interplay between magnetism and superconductivity.
Or, as MIT professor Wolfgang Ketterle put it: "One thing is certain: We have made an important discovery which will advance our understanding of magnetism."
If confirmed, the result may enter textbooks on magnetism.
Sep 21, 2009