A Japanese research team has found a material that could be used to make a low-price super disc with data storage capacity thousands of times greater than a DVD, according to the lead scientist.

The material transforms from a black-colour metal state that conducts electricity into a brown semiconductor when hit by light, according to Shin-ichi Ohkoshi, chemistry professor at the University of Tokyo.

The material, a new crystal form of titanium oxide, can switch back and forth between the metal and semi-conductor states at room temperature when exposed to light, creating an effective on-off function for data storage.

It is "promising as a material for a next-generation optical storage device", said Prof. Ohkoshi.

A material that changes colour with light can be used in storage devices as colours reflect light differently to contain different information.