Phase-change memory, a breakthrough from IBM, may one day replace both your computer’s RAM and flash storage.
The technology has actually been around for nearly two decades, but due to cost and storage density constraints it has only now become feasible to use in consumer products.
The crystal-based storage means “cells are either “on” or “off.” However, IBM researchers have figured out how to save 3-bits of data per cell, dramatically increasing the capacity of the original tech”.
To store PCM data on a Blu-ray disk, you apply a high current to amorphous (non-crystalline) glass materials, transforming them into a more conductive crystale form. To read it back, you apply a lower voltage to measure conductivity — when it’s high, the state is “1,” and when it’s low, it’s “0.”
By heating up the materials, more states can be stored, but the problem is that the crystals can “drift” depending on the ambient temperature. IBM’s team figured out how to track and encode those variations, allowing them to reliably read 3-bits of data per cell long after it was written, reports Endadget.
In practice, that makes PCM much faster than flash storage – but it could retail for the same price as RAM.