Storing data on magnetic tape might sound delightfully retro, but it’s actually still widely in use for archival purposes thanks to its high data density. Now researchers at the University of Tokyo have made magnetic tape using a new material, which allows higher storage density and more protection against interference, as well as a new way to write to the tape using high frequency millimeter waves.
Solid state drives (SSDs), Blu-ray discs and other modern data storage technologies can be quickly written to and read from, but they don’t have the best storage density and can be expensive to scale up. Although magnetic tape hasn’t been popular at the consumer level since about the 1980s, in the realm of data centers and longer term archival storage, its slower speeds are an acceptable price to pay for higher data density.
But there’s always room for improvement of course, and in the new study the Tokyo researchers developed a new storage material, along with a new way to write to it. The team says that it should have a higher storage density, longer lifetime, lower cost, better energy efficiency and higher resistance to outside interference.
“Our new magnetic material is called epsilon iron oxide, it is particularly suitable for long-term digital storage,” says Shinichi Ohkoshi, lead researcher on the study. “When data is written to it, the magnetic states that represent bits become resistant to external stray magnetic fields that might otherwise interfere with the data. We say it has a strong magnetic anisotropy. Of course, this feature also means that it is harder to write the data in the first place; however, we have a novel approach to that part of the process too.”
To write the data, the team developed a new method they call focused-millimeter-wave-assisted magnetic recording (F-MIMR). Millimeter waves at frequencies between 30 and 300 GHz are aimed at strips of epsilon iron oxide, while under the influence of an external magnetic field. That causes the particles on the tape to flip their magnetic direction, which creates a bit of information.
“This is how we overcome what is called in the data science field ‘the magnetic recording trilemma’,” says Marie Yoshikiyo, an author of the study. “The trilemma describes how, to increase storage density, you need smaller magnetic particles, but the smaller particles come with greater instability and the data can easily be lost. So we had to use more stable magnetic materials and produce an entirely new way to write to them. What surprised me was that this process could also be power efficient too.”
The team hasn’t gone into detail on exactly what the new technology’s storage density may be – instead, the study seems to be a proof-of-concept. That means there’s still plenty of work to do, with the team estimating that devices based on the method could hit the market within five to 10 years. In that same time frame we might see many wildly different storage technologies start to break out, such as laser-etched glass slides, holographic films, DNA, and the genomes of living bacteria, though there are always benefits to improving existing infrastructure.
The new research was published in the journal Advanced Materials.
Source: University of Tokyo
