Ultra-thin magnetic metals can enhance AI and rotation

Scientists at the University of Minnesota have discovered how to turn normal non-magnetic metals into magnetic bodies by making them very thin (only two atoms thick).

This discovery could disrupt how we build faster computers and smarter electronic devices, especially for AI applications. The team used advanced growth techniques to create ultra-thin layers of butyric acid dioxide (RUO2), which, despite being more than a billion meters, exhibited surprising magnetic behavior.

Expanding material into new behavior

The key to this discovery is the so-called epitaxial strain – imagine stretching or compressing rubber bands to change their properties. By applying this strain to the atomically thin layer of RUO2, the researchers converted typical nonmagnetic matter into substances with strong magnetic characteristics.

“RUO2 is not only metallic on atomic scales, it is the most metallic material we have observed in any oxide, even elemental metals and 2D materials, behind graphene,” said Bharat Jalan, senior author and professor in the Department of Chemical Engineering and Materials Sciences at the University of Minnesota.

What makes this achievement particularly noteworthy is that even at such extremely high thinness, the material retains its metallic properties. Most materials will become unstable or lose their useful features, reducing them to a few atoms thick.

Anomalous Hall effect breakthrough

The researchers observed what is called anomalous Hall effect – a phenomenon in which the current bends in the presence of a magnetic field. This effect is critical for next-generation memory and data storage devices, but it usually requires the realization of huge magnetic fields in metal RUO2.

This is where the breakthrough becomes important: This effect is achieved using a weaker magnetic field (less than 9 Teslas) compared to the extreme conditions previously required (about 50 Teslas). It’s like getting the same results with a refrigerator magnet instead of requiring a large number of industrial electromagnets.

Key findings include:

• Magnetic effects observed in membranes that are only 2 units of cells thick (less than one billion meters)
• The abnormal hall effect achieved by the magnetic field below 9 Tesla with the previous requirement of about 50 Tesla magnetic field.
• Although very thin, the material remains highly metallic and structurally stable
• The first experimental evidence of Altermignetic state in ultrafine ruO2

Solve scientific debate

This work resolves ongoing scientific controversy over the magnetic properties of RUO2. The abstract notes that the study “solves recent debate” by positioning epitaxial strains as the definite origin of magnetism in these films. Previous studies have contradictory results on whether RUO2 can exhibit magnetic behavior under normal conditions.

The team’s theoretical calculation of density function shows that epitaxial strains stabilize what the researchers call “uncompensated magnetic grounding state”, which actually creates a magnetic imbalance that does not exist in untrained materials.

Beyond the lab’s curiosity

“It’s not only the curiosity of the lab, but we’re working on materials that can be integrated into real devices,” explains Seunnggyo Jeong, a postdoctoral researcher and first author of the paper. “This could have a significant impact on smaller, faster, and more energy-efficient technologies directly associated with AI.”

But why is this important for everyday technology? Current electronic devices waste a lot of energy into heat. Spintronic devices (using electron spins rather than just charges) can greatly reduce this energy loss while increasing processing speed.

Atom’s engineering materials atoms

“This discovery controls entirely new behavior in the material only by controlling the atomic weight,” said Tony Low, a professor in the Department of Electrical, Computer Engineering and co-author. “Our calculations confirm that the strains changed the internal structure of RUO2 in the right way to make this Altermignetic behavior possible.”

The Altermignetic state represents a newly recognized class of magnetic materials that combine the properties of ferromagnets and ferromagnets. This gives researchers greater flexibility in designing materials with specific magnetic behavior.

Future applications and next steps

Particularly promising is the compatibility of the materials with existing manufacturing processes. The researchers used hybrid molecular beam epitaxial, a complex but established technique, to create these ultra-thin films with precise control of thickness and strain.

The team plans to explore how different strain and stratification combinations can design more exotic material properties. Their ultimate goal involves developing platform materials for quantum computing, rotational and low-power electronics that could power next-generation AI systems.

This study shows that understanding how materials unlock entirely new technological possibilities at the atomic level, thus creating a seemingly impossible task of creating magnetic behavior in non-magnetic materials through careful engineering.

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