Researchers from the Netherlands-based Delft University of Technology have created a new storage system that encodes every bit with a single atom. This allows them to fit a kilobyte of data in a space under 100 nanometer across, which equates a storage density of 500 terabits per square inch, or about 500x larger than what's offered by today's hard disk drives.
The storage array (“hard drive” isn’t exactly accurate, but gets the point across) is remarkably elegant in its organization — as it has to be if it is going to work at an atomic level.
“Every bit consists of two positions on a surface of copper atoms, and one chlorine atom that we can slide back and forth between these two positions,” explained Otte. Because chlorine on copper forms into a perfectly square grid, it’s easy (relatively, anyway) to position and read them. If the chlorine atom is up top, that’s a 1; if it’s at the bottom, that’s a 0. Put 8 chlorine atoms in a row and they form a byte.