Advanced Electronics and Quantum Computing through Altermagnetism

Researchers have made a groundbreaking discovery, confirming the existence of a novel magnet type that was previously thought to be impossible. This innovative form of magnetism, referred to as the ‘magic magnet’ or ‘altermagnetism’, offers unique properties that could lead to ultra-fast, energy-efficient electronics and advancements in quantum computing.

New Type of Magnetism: Altermagnetism

Altermagnetism is a novel type of magnetism that diverges from traditional magnetic principles in Physics. First proposed in 2019 by a collaborative team from the Institute of Physics in the Czech Republic and the University of Mainz in Germany, it has recently been confirmed through experimental work at the Swiss Light Source (SLS) in collaboration with scientists from the Czech Academy of Sciences and the Paul Scherrer Institut in Switzerland.

Researchers utilized advanced x-ray imaging techniques to visualize and manipulate this new form of magnetism. Unlike traditional magnets, altermagnets exhibit unique properties that could enable innovative applications in technology. The study, titled “Altermagnetic Lifting of Kramers Spin Degeneracy,” was published in the scientific journal Nature on February 14, 2024.

“That’s the magic of altermagnets,” said Tomáš Jungwirth, a professor at the Institute of Physics at the Czech Academy of Sciences, who led the study.

“Something that people believed was impossible until recent theoretical predictions is in fact possible… And it is not something that exists only in a few obscure materials. It exists in many crystals that people simply had in their drawers. In that sense, now that we have brought it to light, many people around the world will be able to work on it, giving the potential for a broad impact.”

How Altermagnetism Differs from Other Two Types of Magnetism

When discussing magnetism, our thoughts often turn to ferromagnetism—the type of magnetism associated with items like fridge magnets and bar magnets. As taught in school, this form of magnetism follows the principle that opposite poles attract while like poles repel. The exploration of magnetic materials dates back thousands of years, making it one of the earliest sciences. Ferromagnetic materials, such as lodestone, a naturally magnetized variety of the mineral magnetite, captivated the curiosity of ancient civilizations like the Greeks. By the fourth century B.C., the Chinese harnessed this magnetized mineral to create the first compasses (SN: 1/28/11). In contrast, antiferromagnetism was not identified until the 1930s.

The interplay of attraction and repulsion occurs at the atomic scale, driven by the fact that spinning electrons create small magnetic fields. In ferromagnetic materials like iron, cobalt, and nickel, the spins of adjacent electrons can be aligned in the same direction, resulting in a collective magnetic effect. This property makes ferromagnets essential components in devices such as phones and other technologies. However, their application is constrained by the repulsive forces that prevent these materials from being packed too closely together.

A second form of magnetism, identified in the 1930s, is known as antiferromagnetism. Within these substances, the spins of adjacent electrons alternate instead of aligning in parallel. Although these opposing spins create internal magnetic effects, they neutralize one another at a macroscopic level. As a result, antiferromagnetic materials lack the ability to attract or repel objects like regular magnets.

“The idea that there has been a third type of magnetism and we haven’t noticed it, really captures people’s imaginations,” says Felix Flicker, a Bristol University researcher who studies magnetism and author of The Magick of Matter, which draws parallels between scientific phenomena and wizardry. Other forms, he thinks, may be still awaiting discovery.

Altermagnetism appears to merge the advantages of two distinct worlds, showcasing a distinctive form of magnetism that stems from a material’s atomic arrangement. The concept was initially proposed by researchers in Germany and Czechia a few years ago, with the term “altermagnetism” introduced by Libor Šmejkal from the Johannes Gutenberg University of Mainz.

Subsequent strong experimental evidence was gathered by research groups in Korea and China, and ultimate confirmation was provided by an international collaboration that included Šmejkal. Their findings were published in the journal Nature.

Experimental Evidence of Magic Magnet

The researchers investigated manganese telluride crystals, which are considered a leading candidate for altermagnetic materials. As anticipated, the spins of adjacent electrons alternated, causing their opposing spins to cancel each other out externally, similar to what occurs in antiferromagnets. However, the crystal’s atomic arrangement introduced additional complexity, generating an internal magnetic field approximately a thousand times stronger than that of a typical refrigerator magnet.

In essence, the experimental findings confirmed the existence of altermagnetic materials, exhibiting magnetic characteristics that appear ideally suited for enhanced data storage. It is estimated that up to 200 different compounds may possess altermagnetic properties.

Application of Altermagnets 

• Spintronics

The discovery introduces the potential for utilizing the magnetic properties of electrons, rather than their electrical characteristics, to perform computational tasks. This field of study is known as spintronics, as opposed to electronics. “Spintronics”, Flicker says, “gets people excited because it is massively more energy-efficient and computers are increasingly one of the major uses of energy in the world.”

Despite being hailed for years as a transformative technology for the IT industry, spintronics remains in its early stages of development. Traditionally, ferromagnets have been employed in such devices due to their strong spin-dependent physical properties, which are highly advantageous. However, the macroscopic net magnetization typical of ferromagnets, which is beneficial in various other applications, creates challenges for scaling these devices. Specifically, it generates crosstalk between bits, the units of information storage, limiting their practicality for data storage applications.

In recent studies, antiferromagnets have garnered attention in spintronics due to their absence of net magnetization, which enables exceptional scalability and energy efficiency. However, their practical utility has been limited by the lack of strong spin-dependent effects, a key feature of ferromagnets.

This gap is now addressed by altermagnets, which combine the advantages of both systems: they possess zero net magnetization like antiferromagnets while simultaneously exhibiting the robust spin-dependent phenomena typically associated with ferromagnets—features previously thought to be fundamentally incompatible.

• Electronics

The implications of altermagnetism extend to various applications in electronics. Researchers believe that this technology could lead to the creation of ultra-fast, low-power electronic devices with enhanced storage capabilities. The potential applications range from more efficient computer processors to advanced data storage systems, which could fundamentally change the way electronic devices operate. The ability to manipulate magnetic states with precision is expected to facilitate the development of devices that operate at higher speeds while consuming less energy.

• Energy Efficiency

One of the most significant advantages of altermagnetism is its potential to reduce energy consumption in electronic devices. Traditional electronics often grapple with challenges related to power consumption and heat dissipation, which can limit performance and shorten device lifespans. Altermagnetic materials, with their rapid state-switching capabilities, could pave the way for energy-efficient devices that not only enhance operational efficiency but also prolong the lifespan of electronic components. This energy efficiency is critical in a world increasingly focused on sustainable technology solutions.

• Advancements in Quantum Computing

Altermagnetism also holds promise for the field of quantum computing. The ability to precisely manipulate magnetic states is crucial for quantum information processing, where maintaining delicate quantum states without disturbance is essential. The ‘magic magnet’ technology could play a pivotal role in developing more robust and efficient quantum computing systems, potentially transforming the landscape of computing as we know it.

Conclusion

In conclusion, the confirmation of altermagnetism heralds a new era in electronic device design and quantum computing. As researchers continue to explore this ‘magic magnet,’ the potential for groundbreaking advancements in technology remains vast, promising a future where electronic devices are not only more efficient but also more powerful and capable of performing complex tasks with unprecedented speed.