Nanowire ‘racetrack’ memory could be 100,000 times faster

November 16, 2010

Racetrack memory (EPFL)

Imagine a computer equipped with shock-proof memory that’s 100,000 times faster and consumes less power than current hard disks. EPFL Professor Mathias Kläui has invented a new kind of “Racetrack” memory, a high-volume, ultra-rapid read-write magnetic memory that may soon make such a device possible.

Hard disks are cheap and can store enormous quantities of data, but they are slow; every time a computer boots up, 2-3 minutes are lost while information is transferred from the hard disk into RAM (random access memory). The global cost in terms of lost productivity and energy consumption runs into the hundreds of millions of dollars a day.

Kläui’s solution involves data recorded on nickel-iron nanowire, a million times smaller than the classic magnetic tape. And unlike a magnetic videotape, in this system nothing moves mechanically. The bits of information stored in the wire are simply pushed around using a spin polarized current, attaining the breakneck speed of several hundred meters per second in the process. It’s like reading an entire VHS cassette in less than a second.

How it works

For this concept to be feasible, each bit of information must be clearly separated from the next so that the data can be read reliably. Kläui overcame this hurdle by using vortices to create magnetic walls between the bits. Using this solution on a 30 nm thick iron-nickel disk, Kläui and his colleagues recorded even higher reading speeds than expected. Their results were published online October 25, 2010, in the journal Physical Review Letters.

Scientists at the IBM Research Center in Zurich (which is developing a racetrack memory) have confirmed the importance of the discovery, and are planning to collaborate with Kläui to build a prototype. Kläui envisions a system in which millions or even billions of nanowires are embedded in an epoxy resin, providing enormous capacity on a shock-proof platform. A market-ready device could be available in as little as 5-7 years.

Racetrack memory promises to be a breakthrough in data storage and retrieval. Racetrack-equipped computers would boot up instantly, and their information could be accessed 100,000 times more rapidly than with a traditional hard disk.

They would also save energy. RAM needs to be powered every millionth of a second, so an idle computer consumes about .3 Watts just maintaining data in RAM. Because Racetrack memory doesn’t have this constraint, energy consumption could be slashed by a factor of 300, to a mere 1 mW. It’s an important consideration: computing and electronics currently consumes 6% of worldwide electricity, and is forecast to increase to 15% by 2025.

Adapted from materials provided by EPFL