Carbon rings could deliver storage breakthrough

Dresden, Germany – Magnetic media has a couple of rather annoying properties. Not only are the particles used to store data pretty much at the minimum practical size, but they can also spontaneously reverse their magnetic state.

But researchers at the Leibniz Institute for Solid State and Materials Research in Dresden reckon that simply adding cobalt molecules to a carbon ring can enhance the density of magnetic storage by three orders of magnitude while making it stable for significantly longer than the ten years or so possible with current technology.

Reliable magnetic storage depends on how frequently the material used is likely to become bored with storing a one and arbitrarily changing it to a zero. The higher the magnetic anisotropy energy, or MAE, of the material, the longer this period will be.

Cobalt has the highest MAE of all the ferromagnetic elements, which explains its widespread use in magnetic data recording. Each grain of cobalt in today’s storage devices measures about 8nm across and comprises about 50,000 atoms.

While it is theoretically possible to reduce the size of these grains to about 15,000 atoms, it is practically impossible to guarantee the required atomic structure, lowering the MAE and making the media much more likely to lose data unexpectedly.

But the Dresden researchers say that by adding two cobalt atoms to a hexagonal carbon ring of benzene or graphene, one of the atoms bonds with the ring and the magnetic field between the pair of carbon atoms can be switched by applying a weak magnetic and a strong electric field.

As an added bonus, a benzene ring will measure just 0.5nm in diameter, allowing a significant improvement in memory density, while simultaneously guaranteeing reliable storage way beyond the current 10 year limit.

You can download a .PDF of the Dresden paper from here.