Suramya's Blog : Welcome to my crazy life…

June 10, 2021

Using Graphene layers to store 10 times more data in Hard Disks

Filed under: Computer Hardware,Emerging Tech — Suramya @ 5:39 PM

The requirement for data storage has been going up exponentially over the past few years. At the start of 2020 it was estimated that the amount of data in the world was approximately 44 zettabytes (44,000,000,000,000,000,000,000 bytes), by 2025 this number will have grown to 175 zettabytes of data (Source). This means that we need better storage media to store all the information being generated. Imagine having to store this much data on floppy disks with their 1.4MB of storage or the early hard-disks that stored 10MB of data.

New research carried out in collaboration with teams at the University of Exeter, India, Switzerland, Singapore, and the US have replaced the carbon-based overcoats (COCs) which are basically layers on top of hard disk platters to protect them from mechanical damage with 2-4 layers of Graphene. Since we have reduced the thickness of the COC layer the platters can be placed closer together allowing us to have a greater storage density per inch and basically multiply the storage capacity by a factor of ten. Another advantage of using Graphene is that it reduces the corrosion of the platters by 2.5 times thereby making drives more reliable and increasing their lives.

HDDs contain two major components: platters and a head. Data are written on the platters using a magnetic head, which moves rapidly above them as they spin. The space between head and platter is continually decreasing to enable higher densities. Currently, carbon-based overcoats (COCs) — layers used to protect platters from mechanical damages and corrosion — occupy a significant part of this spacing. The data density of HDDs has quadrupled since 1990, and the COC thickness has reduced from 12.5nm to around 3nm, which corresponds to one terabyte per square inch. Now, graphene has enabled researchers to multiply this by ten.

The Cambridge researchers have replaced commercial COCs with one to four layers of graphene, and tested friction, wear, corrosion, thermal stability, and lubricant compatibility. Beyond its unbeatable thinness, graphene fulfills all the ideal properties of an HDD overcoat in terms of corrosion protection, low friction, wear resistance, hardness, lubricant compatibility, and surface smoothness. Graphene enables two-fold reduction in friction and provides better corrosion and wear than state-of-the-art solutions. In fact, one single graphene layer reduces corrosion by 2.5 times. Cambridge scientists transferred graphene onto hard disks made of iron-platinum as the magnetic recording layer, and tested Heat-Assisted Magnetic Recording (HAMR) — a new technology that enables an increase in storage density by heating the recording layer to high temperatures. Current COCs do not perform at these high temperatures, but graphene does. Thus, graphene, coupled with HAMR, can outperform current HDDs, providing an unprecedented data density, higher than 10 terabytes per square inch.

The research was published in Nature: Graphene overcoats for ultra-high storage density magnetic media and has a lot of promise but is still in research phase so it might be a little while before we see consumer products with Graphene layers. A more userfriendly / less technical overview is available at: Phys.org: Ultra-high-density hard drives made with graphene store ten times more data

– Suramya

No Comments »

No comments yet.

RSS feed for comments on this post. TrackBack URL

Leave a comment

Powered by WordPress