New optical disc can store information "for a billion years"
A researcher at the University of Twente in the Netherlands has developed a new optical memory device out of tungsten and silicon nitride that he says could store data safely for extremely long periods of time – up to a billion years.
Hard drives are very susceptible to external magnetic fields and mechanical failures, with a normal lifespan not much longer than 10 years; similarly CDs, DVDs and flash drives each have their own Achilles' heel.
University of Twente researcher Jeroen de Vries set out to solve this problem by designing his own data storing device. For the materials he chose tungsten, which can withstand very high temperatures, encapsulated in silicon nitride, which is highly resistant to fracture and deforms very little when exposed to high levels of heat.
The disc, de Vries claims, is so sturdy that it could be used to store important data on the human race and retain it well past its extinction, for the benefit of whoever is left (of course, that's assuming that the aliens, robots, or mutants will somehow know exactly how to decode the information on the disk in the first place).
From left to right: the QR codes after fabrication, after two hours at 613 K, and after two hours at 763 K (Image: de Vries/University of Twente)
Inside the device, information is stored by etching QR codes in tungsten – which can be easily decoded by today's smartphones. This method is very resilient because the information is still preserved even when up to seven percent of the data has been compromised. Each pixel of the code also has within it a second set of much smaller QR codes, with pixels of only a few microns in size.
To find out how long the device could retain information, de Vries relied on the Arrhenius model, which simulates extended periods of time by exposing the device to predetermined levels of heat for a set amount of time.
The researcher heated the storage device to a temperature of 200 °C (400 °F) for one hour and noted no visible degradation, which according to the model simulates one million years of usage. The device only showed some signs of degradation once it was heated to much higher temperatures, around 440 °C (820 °F) – but even then, the tungsten was not harmed and the data was still readable.
Though the mathematical model used for testing was limited to exposure to high temperatures (and, as the researcher admits, may not be entirely accurate), de Vries says that if they can find a place that is very stable to store the device, such as a nuclear storage facility, then the disc and the data it contains still has all the requisites to last for extremely long periods of time, on the order of millions of years.
The video below shows the researcher putting the device through some ... rather unusual testing.
Source: University of Twente