Whether it’s on your laptop or in a data centre, extra storage is always welcome. Now, it’s been shown that heat-assisted magnetic storage could let us squeeze over ten times more data into the same volume.
Heat-assisted magnetic recording uses a laser beams as well as a magnetic field to write data to magnetic storage. It’s been proposed to overcome what’s known as the “magnetic recording trilemma”, which describes the need to balance readability, writability, and stability. Make the magnetic grains used to store data too small, and their surroundings can cause their magnetic field to drift, destroying the stored data.
The solution is to use magnetic material that’s more resistant to these effects — but that in turn makes it harder to write to in the first place, which in turn demands bigger magnetic fields which interfere with surrounding grain. By heating a magnetic grain using a laser, though, it’s possible to lower the field required to write the data. And by isolating it using the laser, its possible to write data to a single tiny spot, without affecting neighbouring grains.
But while the method’s existed for a while, we’ve yet to understand the limits of what it could deliver. Now, though, a series of simulations performed by researchers from TU Wien in Vienna, Austria, have shown that the technique could be used to squeeze as much as 13.23 Terabits into a square-inch. For some context, Blu-ray disks pack in 12.5 Gbits/in^2 and the best hard drives 1.34 Tbits/in^2 — so that’s a potential increase in storage density of more than ten times. The research is published in Applied Physics Letters.
The only problem now is putting theory into practice. Incorporating an accurate laser system into the storage device with grain structures accurate enough to achieve the high storage densities is... challenging. But, the researchers claims, it is “expected to be [feasible] within the next years.” [Applied Physics Letters via PhysOrg]