Turkish scientists have used different colour combinations of polymers to make memory devices that can store up to 10²³ different pieces of data.

The husband and wife team, Gursel* and Hayal Sonmez at Sabanci University, used electrochromic polymers to make three devices that store data by using optical changes at a specific wavelength.

Each device operates slightly differently, although they all combine layers of polymer films with electrolyte. The conducting electrochromic polymers are the active layer in the device. Information is stored using different colours and absorption intensities. Mixing any two colours in various oxidation states of the polymer can create thousands more colours. As many as 2.62 × 10²³ combinations are possible with a 3 × 3 pixel device. Even more would be possible with more pixels.

These devices will be particularly useful because of the low power requirements and the varying colours and shades that result from the many polymer oxidation states possible, said Hayal Sonmez.

But storage isn't the only consideration, she said. 'The most important components for these devices are the detectors. Now it is worth looking to improve the properties of the detectors.'

Sophia Anderton

* Gursel Sonmez tragically died in an accident while this article was in the process of publication.