LONDON (TIP): Faster, smaller, greener computers, capable of processing information up to 1,000 times quicker than currently available models, could be made possible by replacing silicon with phase-change materials, according to a new study. Researchers found that the present size and speed limitations of computer processors and memory could be overcome by replacing silicon with ‘phase-change materials’ (PCMs).

PCMs are capable of reversibly switching between two structural phases with different electrical states – one crystalline and conducting and the other glassy and insulating – in billionths of a second. Modelling and tests of PCM-based devices showed that logic-processing operations can be performed in non-volatile memory cells using particular combinations of ultra-short voltage pulses, which is not possible with silicon-based devices.

In these new devices, logic operations and memory are co-located, rather than separated, as they are in siliconbased computers. These materials could enable processing speeds between 500 and 1,000 times faster than the current average laptop, while using less energy. The processors, designed by researchers from the University of Cambridge, the Singapore A STAR Data- Storage Institute and the Singapore University of Technology and Design, use a type of PCM based on a chalcogenide glass, which can be melted and recrystallized in as little as half a nanosecond using right voltage pulses.