Continuing the atypical storage medium series, we present you the glass disk storage. This storage medium may seem a little less futuristic when compared with the previously introduced liquid storage, yet it is another amazing alternative hard drive concept.
The quartz glass optical memory technology belongs to a team of researchers from the University of Southampton (and the Eindhoven University of Technology, according to this 2013 source). The team leader is Jingyu Zhang, who holds a Southampton PhD in optoelectronics, and graduated in 2009 the Huazhong University of Science and Technology.
Nanostructured glass storage disk: capacity
Since this optical memory is “five-dimensional” and allows the inscription of a vast quantity of data by using a high-speed (femtosecond) laser, the name of 5D memory has already been established, as well as the denomination of 5D method for this particular type of data writing. It all concerns the three-dimensional characteristic of the optical nanostructures being supplemented by yet another two dimensions: the refraction and the polarization parameters that also count as data-writing space.
What is the capacity of this nanostructured glass disk? Maybe it has caught your eye in the news before, since it’s an impressive 360 TB of data. Qualifying as an unprecedented storage capacity, this ability has lived up to its previous 2013 promises when the Southampton scientists have actually written quite a few digital documents on the prototype disk in 2015.
The current team, whose press liaison is Peter Kazansky, one of the team members and a researcher from the Optoelectronics Research Center (ORC), has saved copies of the Universal Declaration of Human Rights (UDHR), Newton’s Opticks, The Magna Carta and The King James Bible on the tiny glass disk.
Previously in 2013 the team has demonstrated that 300 kilobytes of text can actually be written on the five-dimensional glass disk. Now it was the matter of how much data can be fitted on the new storage surface that got a successful demonstration. The technology authors have already hinted by their choice of data that expected commercial applications involve national archives, museums, libraries and other institutions interested in the large-scale digital preservation of documents – and in the digital documents’ long-term survival, as well.
Nanostructured glass storage disk: life duration
The 5D disk creators have boldly estimated a life duration of up to 13.8 billion years at the extreme temperature of 190 degrees Celsius and a virtually unlimited life duration at normal (room) temperature. Since this “eternal” data storage technology is built for resilience in harsh environments, we must also add that its thermal stability mentions a limit of 1000 degrees Celsius; these characteristics have led to the idea that data such inscribed might actually survive the human race itself.
UNESCO underlined the symbolic value of this glass disk by presenting it at the 2015 International Year of Light (and light-based technologies) – IYL’s closing event from Mexico. It is not difficult to visualize how such a storage environment could easily become a modern artifact, depending on the valuable digital data written on it.
Nanostructured glass storage disk: a new era in storage
Considering all of the above, the storage industry is presented with “a very stable and safe form of portable memory” in the form of this tiny glass disk with a vast capacity and an unmatched-before resistance to extreme conditions.
The end-of-the-world paradigm aside, such a storage environment could provide a welcomed solution to the physical storage issue: when digitizing huge archives new problems arise. The current situation presumes the existence of secured storage spaces for hard-drives and optical disks, spaces that have to be available, to be endowed with humidity controllers and with fireproof systems – which translates into big physical spaces and controlled environments. All these requirements in turn need financial backing and careful planning; otherwise the stored data may be lost or damaged.
Storing digital documents on tiny nanostructured glass disks clearly would reduce the amount of space needed, as well as the microenvironment requirements. It might just prove much more efficient than the classical digital storage system – a thing that remains to be seen as soon as this emerging technology becomes widely available on the market and comes with price and maintenance specifications.
Nanostructured glass storage disk – how is the data imprinted on the glass?
The technology used for writing the data on the glass disks involves a femtosecond laser (a laser that moves extremely fast). The pulses of light produced by the laser have a very short duration: 10−15 seconds each.
In the case of this Southampton University technology, each pulse takes 280 femtoseconds, or 280 quadrillionths of a second to imprint spots on the glass, spots that represent the actual data. These dots are distributed in layers and have five micrometers (0.005mm) distances between them. The layers first occupy the three usual dimensions of the glass disk, and then move on to the extra two dimensions by using a special technique that involves moving the laser horizontally and vertically.
In order to read the data the users must possess an optical microscope, by the help of which the polarized light is untangled and accessed.
Most likely the available online media description of the processes involved serve in forming an idea about the entire succession of actions, even for those who are not optical storage specialists, yet whom might be interested in benefiting from this technology or from other similar techniques. For the more curious readers, a short paper on this technology is accessible here.
Another interesting lecture would be this 2009 online article that mentions the spots or bits of data technique being discovered by a team of researchers from Swinburne University of Technology in Melbourne, Australia, and having the backing of Samsung Electronics. At that time the technology was expected to be implemented on DVDs or future compatible optical drives, and it was two-dimensional.
We can clearly link the two together and have an image of how various technologies meet at a distance in time to form new viable devices and related systems that ultimately accumulate and determine progress itself.