With an advanced version of the technology behind DVDs and Blu-rays, much more data can be stored than before, although it will take a while.

A new method of writing data to laser glass allows 500 terabytes to be stored on a single optical disc. It takes so long to write that applications are likely to be limited.

The method uses the same technology as existing optical storage media, but can store 10,000 times more data than Blu-ray discs. It is a laser that emits pulses every femtosecond, one quadrillionth of a second, that make small holes in the glass.

Five dimensions

Yuhao Lei, a PhD student in optoelectronics at the University of Southampton in the UK, and his colleagues call the new method “five-dimensional optical data storage.” The method uses two optical dimensions, based on polarization and light intensity, in addition to the usual three spatial dimensions.

In one experiment, the researchers managed to write 6 gigabytes on a square of glass approximately 6.5 centimeters square. They were able to re-read the data with an accuracy of between 96.3 and 99.5 percent, which could have been 100 percent if they had used an error correction algorithm, Lei says.

Save faster

“Our biggest challenge was storage speed,” he says, since the researchers could only store 225 kilobytes per second. That means 6 gigabytes would take about 6 hours. ‘At the moment we do not store in parallel (where several lasers write on the material, ed.). We’re trying to improve that. ‘

“This data storage is very durable and can withstand high temperatures, which means it has an almost eternal life,” said team member Peter Kazansky, professor of optoelectronics at the University of Southampton.

With minor tweaks, the storage speed can be four times faster, Kazansky says, although he thinks that could significantly increase the chance for errors. The ultimate goal is to develop a national archive storage method, Lei says.

“It is fantastic to see the major improvements in storage speed and overall performance of this laboratory storage technology that have been made in just a few years,” said Ben Fino-Radin, founder of New Archiving Company. York Small Data Industries. It refers to an improvement in technology by a factor of 75 compared to 2017. At that time, only three kilobytes per second could be stored. “It is not clear what practical role 5D glass storage could play in the future.”