Excerpt from worldtechtoday.com
A group of researchers at the Princeton University has found that
frustrated magnets, inspite of not possessing any magnetic feature at
low temperatures, do exhibit features of Hall Effect. ‘Frustrated’
magnets are so called because of their inability of getting a long range
magnetic order inspite of a huge exchange between the spins of their
elementary particles.
The Hall Effect suggests that when magnetic field is applied to
electric current carried by charged particles present in a conductor, it
causes magnet to bend to the other side of semi-conductor. They are of
great interest in physics and material science. Appreciating that
frustrated magnets are capable of producing Hall Effect could hold the
key to future advances in computing and the creation of devices such as
quantum computers.
“To talk about the Hall Effect for neutral particles is an oxymoron, a
crazy idea,” said N. Phuan Ong, one of the authors of the study and
Eugene Higgins Professor of Physics at Princeton.
Inspite of that, he together with his colleague, Princeton’s Russell
Wellman Moore Professor of Chemistry as well as their graduate students
Max Hirschberger and Jason Krizan witnessed this unusual behavior in
frustrated magnets.
“All of us were very surprised because we work and play in the
classical, non-quantum world. Quantum behavior can seem very strange,
and this is one example where something that shouldn’t happen is in
reality there. It really exists,” said Ong in a statement.
The researchers wanted to find out the reason underlying “discontent” nature of Hall Effect.
In this particular case, the team led by Ong and Moore studied
pyrochlores, a class of magnets ‘which should have orderly “spins” at
very low temperature, but have been found to have spins that point in
random directions, thus rendering them with magnetic frustration
properties.’ They attached small electrodes to both sides of crystals
and later passed heat through them using microheaters at extremely low
temperatures.
The outcome of the experiment, states Ong, stunned the entire team.
Source Article from http://feedproxy.google.com/~r/AscensionEarth2012/~3/E42WfGKfguE/frustrated-magnets-showing-features-of.html
Frustrated magnets showing features of Hall Effect stun Princeton University researchers
No comments:
Post a Comment