The data density of hard drives has quadrupled since 1990 to today peak at 1 TB per square inch. To go much further, it is necessary to rely on the use of one of the researchers’ favorite materials: graphene. By combining it with a high temperature storage method, it could increase the storage capacity per square inch tenfold.
On matter storage, little more than the SSD drives with their reliability, speed and low power consumptionenergy. Their only constraint remains their storage capacity, which is still limited for large data consumers. It is still in this niche that mechanical hard drives still manage to resist. While the density of hard drives has quadrupled since the 1990s, it could be multiplied by 10 using the material with multiple virtues: the graphene. An international team of these researchers from Cambridge universities and Exeter in the United Kingdom, but also from India, Switzerland, Singapore and the United States, have just published in Nature, a study that could give the mechanical hard drive industry a big boost.
They explain that the use of graphene increases storage density tenfold. Mechanical hard disks are made up of circular platters hovered over by magnetic read-write heads. It is the space between this head and the surface of the plate which is continuously reduced in order to increase the densities. But there is a limit physique. That which comes from a coating made up of carbone. It allows both to protect the trays from shocks andoxidation. Since 1990, this thickness has increased from 12.5nm to around 3nm, which is equivalent to one terabyte per square inch. Efforts to go further are becoming increasingly problematic. But, with the properties of graphene, the rules of the game will change.
A density multiplied by ten
Thus, the team tested trays with one to four layers of graphene to test the resistance to the friction, wear, the corrosion, the thermal stability. Tests that have finally shown that graphene goes beyond expectations. It thus appears that a single layer of graphene reduces oxidation by 2.5 times. Even better, Cambridge researchers have applied graphene to hard drives made of one alloy iron-platinum. They were then able to test a magnetic recording method assisted by the heat baptized HAMR (Heat Assisted Magnetic Recording). With graphene, this method, which is nothing new, makes it possible to increase the storage density by heating the magnetic layer at high temperature.
A temperature that the layers of carbone current. Finally, by combining the robustness of graphene with this method, it is 10 TB that it is possible to store on a square inch, that is to say 10 times more than today. Another advantage: graphene makes it possible to increase the reliability and duration life of the discs despite this high temperature treatment. For once, the discs can extend their life expectancy while increasing their storage capacity tenfold. It remains to be seen whether the industrialization of these technologies can be done economically. In any case, as always, there is something magical about this material as soon as it is mined.
What you must remember
- By replacing the carbon layer of hard drives with graphene, it is possible to increase storage density tenfold.
- Combining graphene with a high temperature writing method increases the capacity.
Interested in what you just read?