According to NanoWerk, UC Riverside researchers have come up with a memory device
based on telescoping multi-walled carbon nanotubes
. According to one of the researchers, 'This finding leads to a promising potential to build ultrafast high-density nonvolatile memory, up to 100 gigahertz or into the terahertz range" and a prototype could be demonstrated "in the next two to three years.' Similar devices from UCLA and Caltech
based on bistable rotaxanes
are farther along in being integrated into actual memory circuits, but tend to break after a fairly small number of position changes. Carbon nanotubes may promise more durable switches.