A New Type of Magnet Has Been Discovered

The novel robust magnet has potential future applications in producing more effective data storage technologies.

Loukia Papadopoulos
A New Type of Magnet Has Been Discovered

We don’t think about magnets much in real life and yet they have some impressive uses such as in data storage applications.

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Those applications are called magnetic recordings, and they consist of the storage of data on a magnetized medium in the form of non-volatile memory. 

Now, a team of scientists may have discovered a new type of magnet that holds the promise of improving data storage.

“There’s a great deal of research these days into the use of magnets and magnetism to improve data storage technologies,” explained Andrew Wray, an assistant professor of physics at New York University, who led the research team.

Singlet-based magnet

What this team uncovered is called a “singlet-based” magnet. This type of magnet has fields that pop in and out of existence as opposed to the small magnetic constituents that exist in its current counterparts. 

As such, singlet-based magnets exhibit an unstable force but one that could offer a lot more flexibility. 

“Singlet-based magnets should have a more sudden transition between magnetic and non-magnetic phases. You don’t need to do as much to get the material to flip between non-magnetic and strongly magnetic states, which could be beneficial for power consumption and switching speed inside a computer,” said Wray.

“There’s also a big difference in how this kind of magnetism couples with electric currents. Electrons coming into the material interact very strongly with the unstable magnetic moments, rather than simply passing through. Therefore, it’s possible that these characteristics can help with performance bottlenecks and allow better control of magnetically stored information,” continued Wray.

new magnet
Source: Lin Miao, NYU’s Department of Physics

Spin exciton

Although the type of battery is entirely new, the idea behind it is 50 years old. Today’s typical magnets feature tiny “magnetic moments” that work together to create a magnetic field.

However, in the 1960s a theory had emerged that speculated that magnets could exist without these moments. At first glance, it sounded impossible until the discovery of a kind of temporary magnetic moment called a “spin exciton.” 

“A single spin exciton tends to disappear in short order, but when you have a lot of them, the theory suggested that they can stabilize each other and catalyze the appearance of even more spin excitons, in a kind of cascade,” Wray explained.

The researchers went on the hunt to find magnet candidates that could exhibit spin excitons but although there had been some options in the 1970s, these only produced stable magnetism at extremely low temperatures.

That is until they uncovered USb2, a robust magnet that even exhibited Hundness. Hundness is a key property that controls how electrons generate magnetic moments, a much-desired trait for quantum mechanical properties such as superconductivity.

“This material had been quite an enigma for the last couple of decades–the ways that magnetism and electricity talk to one another inside it were known to be bizarre and only begin to make sense with this new classification,” remarked Lin Miao, an NYU postdoctoral fellow and the paper’s first author.