Their study demonstrates conclusively that phase-change materials can store and process information simultaneously. It also shows experimentally for the first time that they can perform general-purpose computing operations, such as addition, subtraction, multiplication and division. More strikingly perhaps it shows that phase-change materials can be used to make artificial neurons and synapses. This means that an artificial system made entirely from phase-change devices could potentially learn and process information in a similar way to our own brains.
This weekend nextbigfuture had covered Thomas N Theis, Program Manager, New Devices and Architectures for Computing IBM Watson Research Center He indicated that IBM is spending a lot of research effort and resources and within a few years of products for : New logic devices, new phase change memory and new silicon photonics for exaflop and zettaflop computers.
The power level and performance of onchip photonics that will enable zettaflop supercomputers is described here.