Within your computer’s hard drive, there is a spinning disk coated in a thin-film of magnetic material. This film is where all the data reading and writing happens, and the denser the magnetic material is, the more data you can pack on the disk.
Since they were first theorized in the ’60s, scientists have thought that skyrmions–knots of magnetic atoms–might make a good replacement for the iron-based magnetic materials currently used in hard drives. These current materials become unstable when they overheat or are packed too closely, placing limits on how much information can be written onto a hard drive. Skyrmions remain stable; even if they are moved around, their structure does not unravel. That means you could pack a disk surface with them more densely, potentially leading to a hard drive that can store 20 times more data.
University of Hamburg physicists revealed in Science (subscription required) on Friday that they can now create and destroy skyrmions at will. The team was able to create four at a time, but their technique only worked 60 percent of the time. It also only succeeded at extremely cold temperatures that would never naturally exist in a hard drive. They will continue to experiment and create models to improve on the work.
Skyrmions have been observed in the past, but never created by humans. The researchers made them by blasting atoms that had not yet been tied into a skyrmion with polarized electrons. The electrons’ magnetic force twisted the atoms together into skyrmions. The same force could also be used to untie the atoms.
“We transferred the idea of tying a knot to memorize something to the field of storage technology so we can now store data in a two-dimensional magnetic knot,” Ph.D. student Niklas Romming said in a release.