Scientists are studying a new kind of magnetism called altermagnetism.
Altermagnetism is when tiny magnetic parts align opposite to their neighbors, but each part sits in a structure that is slightly rotated compared to others. This is different from the usual types of magnetism, like ferromagnetism or antiferromagnetism.
Altermagnets have magnetic moments that point in opposite directions, but their crystal structures are twisted.
Researchers at the University of Nottingham have found ways to control altermagnetism in tiny devices.
“Altermagnets consist of magnetic moments that point antiparallel to their neighbours," says research leader Peter Wadley in a press release issued by the University of Nottingham. "However, each part of the crystal hosting these tiny moments is rotated with respect to its neighbours."
"This is like antiferromagnetism with a twist! But this subtle difference has huge ramifications,” he says.
This twist gives altermagnets unique properties that could revolutionize technology and make computer memory devices much faster, up to a thousand times quicker.
The researchers have described the methods and results of this study in a paper published in Nature.
The experiments took place at the MAX IV facility in Sweden, which is an electron accelerator that produces x-rays and uses them to look at materials. Scientists shine x-rays on the magnetic material, and the electrons that come off show what's happening inside. This method lets them see the magnetism at a very small scale, down to the nanoscale.
Faster and cleaner electronics
Magnetic materials are key in computer memory and electronics, but they use a lot of energy and rely on rare, harmful materials. Altermagnetism might solve these problems. It combines good traits from other types of magnetism, potentially making devices faster, more durable, and less energy-consuming.
According to the researchers, replacing the key components of microelectronic devices with altermagnetic materials could permit increasing speed and efficiency. At the same time, it could reduce our dependency on rare and toxic heavy elements.