A quantum-mechanical memory component that might replace the electronic memories used for decades in computers and other gadgets has come closer to practicality, thanks to improvements achieved by research teams in the United States and Japan.
Current electronic devices rely mainly on two types of on-chip memory—static random access memory and dynamic random access memory, which is more compact. These memories can be accessed quickly, but they're volatile—shutting off power erases the data. Nonvolatile memory, such as hard disks, takes longer to access.
Although other types of nonvolatile memory are increasingly available—for instance, the flash memory in a digital camera—such storage options typically cost more per bit and hold less data than disks do or have slow access times.