Although the world is currently enamored of flash memory, today’s standard for solid-state storage, companies like IBM need to think a few years ahead. One of the technologies they’re looking at is called phase-change memory, in which a memory cell changes from a crystalline to amorphous phase, changing its resistance. Put a bunch of those together, and you’ve got yourself a binary storage system.
The trouble was that they couldn’t store more than one bit per cell, which means the tech couldn’t really scale. They’ve just figured that out, though: they assigned four discrete resistance levels (i.e. phase states) to represent “00,” “01,” “10,” and “11.” A clever and elegant solution that circumvents the problem completely. They also came up with a way of controlling for the fact that the resistance level tends to drift over time.
Interested? There’s much more to read over at IBM Zurich’s Research blog. You’re not going to be seeing this type of memory for a while, though; IBM puts “wide adoption” in 2016. We’ll update you then.