By leveraging the wonder material graphene, a group at the University of Cambridge is claiming an advance in data storage that resembles more of a leap than a step forward. The new design unlocks higher operating temperatures for hard disk drives (HDDs) and with it, unprecedented data density, which the team says represents a ten-fold increase on current technologies.
In a HDD, data is written onto fast-spinning platters by a moving magnetic head. Special layers called carbon-based overcoats (COCs) protect these platters from mechanical damage and corrosion during operation, though these can only perform within a certain temperature range and also take up a lot of space.
The Cambridge researchers were able to replace the COCs used in commercial HDDs with between one and four layers of graphene, a material that is a single layer of carbon atoms with incredible strength and flexibility, among other highly-valued properties. The thinness of the graphene enabled significant space savings but also outperformed current COCs in preventing mechanical wear, reduced corrosion by 2.5 times and also offered a two-fold reduction in friction.
But most promisingly, the incorporation of the graphene layers increased the operating temperature the HDD was capable of. This is because it enabled the team to use an advanced writing technology called Heat-Assisted Magnetic Recording (HAMR), which heats the recording layer to higher temperatures and allows data bits to be far smaller and more tightly packed together, while remaining stable.
HAMR is incompatible with current-day COCs, but the wonder material graphene can take the heat. The combination of this with the space-savings led to what the scientists say is an unprecedented data density of 10 terabytes per square inch, a tenfold increase on today’s solutions.
“Demonstrating that graphene can serve as protective coating for conventional hard disk drives and that it is able to withstand HAMR conditions is a very important result,” says Dr Anna Ott from the Cambridge Graphene Centre, one of the co-authors of this study. “This will further push the development of novel high areal density hard disk drives.”
The research was published in the journal Nature Communications.
Source: University of Cambridge