Storage space is something we can rarely have enough of. The more storage space you get, you tend to become less frugal and use it all up. We clearly remember the days when a few MegaBytes of RAM were enough up until six months later when the new 256 MB sticks came out and all applications started needing more RAM than what you had. Maybe you didn’t connect with that example, how about the more recent example of smartphones where 64 GB has become the new “norm”, up from 16 GB about 2 years back. Suffice to say, we can never have enough storage space but there’s a new technology on the horizon which might just satiate our hunger for more storage space. It’s made of nanoparticle-based films that are more than 80 times thinner than a strand of hair and it might just enable us to store 1000 times more data than a DVD in a 10×10 cms piece of film. Also, did we mention that it holographically archives data?
Evolution of storage technology
Ever since IBM shipped the first hard drive in the RAMAC system back in 1956 at USD 10,000 / MB of data, the need to have more has always been there. Often, we’ve only seen incremental changes in storage technology interspersed with huge improvements. However, the overall improvement in areal density hasn’t improved by leaps and bounds.
The late ‘50s and early ‘60s show a significant spurt in areal density before slowing down till the mid-‘90s. That’s when the first MR (Magnetoresistance) head came to be that allowed for higher density. Then there was GMR (Giant Magnetoresistance) head which helped in a small way and if you’ve bought your hard drive in the last couple of years then you drive uses something called Perpendicular Magnetic Recording or PMR+. The more recent technology to be implemented in the mass production of the hard drive is SMR (Shingled Magnetic Recording) and that has enabled hard drives of 8 TB and above possible. However, your next hard drive is likely to use something called HAMR (Heat Assisted Magnetic Recording).
HAMR is quite promising because it has the potential to change the rate of growth of areal density by 30 percent per year. That’s double the current trend of 15 percent. If the new nano-particle based film storage technology enters mass production, then we’re looking at the largest spike in areal density that the storage industry will have seen.
Made in China
Currently, under development at the Northeast Normal University, China, this new technology is a different storage medium altogether. So no, your hard drives are not going to be enhanced by this technology. It’s being built to record holographic information. The nanoparticle film in question can be incorporated into a tiny storage chip that records 3D colour information which can be realised as a 3D hologram. That too, with realistic detail.
Moreover, it’s quite durable as well. Shencheng Fu, the lead researcher on the project claims that the storage medium is environmentally stable to the extent that it can function in the harsh radiation conditions of outer space. They not only hold massive amounts of data but the same data can be retrieved at speeds of up to 1 Gbps.
In order to understand the new medium, you need to know the drawbacks of similar media that already exist. As of now, porous films made out of semiconductor titania and silver nanoparticles have shown much promise for storing nanoscale holograms because they change colour when hit by different wavelengths of laser light. Also, the method can be used to store a set of 3D images using a laser in a single step. However, there is a drawback to this technology, one that has plagued silicon for quite some time – Ultraviolet Light. Exposure to UV light can erase the data stored on these media, hence, it becomes unviable for long-term data storage. You can try this out yourself by taking a UV LED and flashing it over the window atop an EPROM chip.
This vulnerability exists because recording a holographic image onto titania-silver medium requires the use of a laser that converts the silver particles into silver cations because it gained extra electrons. Unfortunately, UV light has the same effect as the laser on the medium. When struck by UV light, the electrons from the semiconductor film transfer onto the silver nanoparticles, and thus converts the silver particles into cations. This results in the data getting erased.
The key change in the new research by Shencheng Fu was the introduction of electron-accepting molecules into the medium. When struck by UV light, the excess electrons would be drawn to the new molecules rather than the silver particles. This mitigated the effect of UV light and made the medium more stable and durable for use in the hazardous radiation conditions of space.
In order to make the new films, researchers had to use electron-accepting molecules that were only 1-2 nanometers thick. They fabricated the nanoparticle films with a honeycomb nanopore structure so that all three components, i.e. the silver nanoparticles, the semiconductor and the electron-accepting molecule could all interface with each other. As a result, the final nanoparticle films were just 620 nm thick.
So when can I buy it?
Not anytime soon. While the technology has been proven to be durable and capable of storing massive amounts of data, it will remain within the confines of the research facility for the time being. That’s because the researchers indicate that real-world application of these nanoparticle films would require the development of high-efficiency 3D image reconstruction techniques and also methods to depict data that are stored in different colours. Until these things are developed and miniaturised to fit in your average hard drive, you’ll have to stick with HAMR hard drives or maybe the MAMR (Microwave Assisted Magnetic Recording) drives which are right around the corner.