The magnets on your fridge will be more than just fancy embellishments and buttons to keep your reminders. Soon, perhaps ten years later, it can be the answer to an energy-efficient and practical version of today's refrigerators.
Thanks to a team of researchers at the University of Virginia, who recently uncovered a new nonlinear property in metamagnets, a "universal law" which can be used in home appliances and other possible ways.
Metamagnets are metal alloys that, when combined with a little magnetic field emitted by outside source such as a permanent magnet or an electromagnet, can exhibit an amplified amount of magnetization.
The scientists found out that the magnetism of most metamagnets are nonlinear, meaning the strength produced by the metamagnets when placed in a magnetic field that is doubled could be on par with the energy required in, for example, charging refrigeration.
"A very useful property of this type of magnetism is in magnetic refrigeration," said lead author of the study Bellave Shivaram. "Magnetic refrigerators are not commonplace; they still are in the experimental stage. But they could eventually become part of everyday home appliances."
The study does not guarantee the metamagnets' full potential in refrigerators yet, as they could only be used as coolants at extremely low temperatures with the help of superconducting magnets. However, further studies about the metamagnets may uncover more of its uses, especially as part of home appliances, Shivaram noted.
Refrigerators manufactured these days are costly, because they are assembled from several moving parts, not to mention the huge amount of energy they consume in every household. Furthermore, they deplete the ozone layer with the fluorocarbons they might emit should they leak due to damage.
"Refrigerators of the future, using metamagnets, would have fewer moving parts, would not require refrigerants, and, likely would use less electricity," Shivaram said.
If exploited properly, the practicality of the metamagnets are endless. In fact, may be even used to power heat pumps and screening devices in airports. Metamagnets can produce the necessary amount of terahertz needed to fire up screeners through transformation of radio waves to terahertz waves.
Shivaram, who is also a University of Virginia professor of physics who led the studies, conducted the study in his lab together with his team and employed materials from the Argonne National Laboratory in Illinois.
Online copies of the study can be found in the journal Review of Scientific Instruments and Physical Review B: Rapid Communications.
