Researchers explored the possibility of antiferromagnetic materials as a potential candidate for next generation data storage technologies.
With an increasing use of big data technologies and cloud-based services, there is a constantly growing demand for data storage and faster data processing technologies. “The estimates say that the growing demand can only be met for a limited period of about 10 years, if no novel, more efficient technologies for data storage and processing can be developed in the meantime,” says physicist Dr. Davide Bossini from the University of Konstanz and lead author of the study.
Keeping building data centers as the demand continues to grow is not a viable option. There is a need for faster and more energy-efficient than traditional mass data storage, based on magnetic hard disks. Antiferromagnets is a promising candidate for next generation data storage technologies.
Conventional ferromagnetic materials have atoms that are magnetically all oriented in the same direction, so that a magnetic polarization (magnetization) occurs that affects the surrounding environment. The antiferromagnets, on the other hand, have atoms with alternating magnetic moments that cancel each other out. Therefore do not have any net magnetization.
Inside the antiferromagnetic materials are the so-called domains, which are separated from each other by transitional areas known as “domain walls.” “Although these transitional areas are well-known in antiferromagnets, until now, little was known about the influence the domain walls have on the magnetic properties of antiferromagnets—especially during extremely short time increments,” says Dr. Bossini.
The researchers describe in their paper published in the journal Physical Review Letters about what happens when antiferromagnets are exposed to ultrafast (femtosecond) laser pulses. They also showed that domain walls play an active role in the dynamic properties of the antiferromagnet nickel oxide. Their experiments revealed that magnetic waves with different frequencies could be induced, amplified and even coupled with each other across different domains—but only in the presence of domain walls.
“Our observations show that the ubiquitous presence of domain walls in antiferromagnets could potentially be used to endow these materials with new functionalities at the ultrafast scale,” Bossini explains.
Researchers conclude that antiferromagnetic materials are ideal for future technologies, and as the materials have no net magnetization, they would also be less vulnerable to malfunctions and external manipulation.
“Future technologies based on antiferromagnets would thus meet all the requirements for the next generation of data storage technology. They also have the potential to keep pace with the growing demand for data storage and processing capacity,” concludes Bossini.