Scientists have discovered a new state of magnetism in atomically thin materials that could pave the way for data storage devices capable of holding vast amounts of information in ever-smaller spaces.
In a study published by the University of Stuttgart, an international research team reveals how they manipulated layers of chromium iodide — a “two-dimensional” material just a few atoms thick — to create a magnetic state that is robust against environmental interference.
“As data volumes continue to grow, future magnetic storage media must be able to store information reliably at ever higher densities,” says Professor Jörg Wrachtrup, Head of the Center for Applied Quantum Technologies (ZAQuant) at the University of Stuttgart. “Our results are therefore directly relevant for next-generation data storage technologies.”
The magic twist
The breakthrough centres on a phenomenon known as “twisting”. By slightly rotating two bilayers of chromium iodide relative to one another, the researchers unlocked magnetic properties that do not exist in the material’s natural state.
“In contrast, an untwisted bilayer does not exhibit a net external magnetic field,” explains Dr. Ruoming Peng, a postdoctoral researcher at the university’s 3rd Physics Institute.
This twisting action gave rise to “skyrmions” — tiny, swirling magnetic structures that are among the smallest and most stable information carriers known to science. This marks the first time skyrmions have been created and directly detected in a twisted 2D magnetic material.
Sensing the invisible
Detecting these signals required extreme precision. The magnetic fields generated were so weak that standard equipment couldn’t see them. To overcome this, the team used a highly specialised microscope based on quantum sensing techniques, exploiting nitrogen-vacancy (NV) centres in diamond to detect the faint magnetic signatures.
The discovery challenges current scientific understanding. “Our experimental results indicate that existing theoretical models need to be refined to fully capture the observed phenomena,” says Wrachtrup.