Tiny, high-capacity "atomristor" stores data in single-atom switches
Engineers at the University of Texas have created one of the smallest memory storage devices ever, made out of a two-dimensional material measuring one nanometer square. Dubbed an “atomristor,” the device works on the movements of single atoms, which could pave the way for much smaller memory systems with incredible information density.
The new device belongs to an emerging class of electronics called memristors, which store data using resistive switching. Essentially, when a certain material is exposed to a certain voltage, its electrical resistance can switch, becoming stronger or weaker. This phenomenon can be used to write data to a device, and its relative resistance can be measured later to “read” the stored data.
In this case, that resistive switching is handled by single atoms moving into and out of nanoscale holes, which changes the conductivity of the material. The material in question is molybdenum disulfide (MoS2), although the team says that the concept should also apply to a range of similar materials.
“The scientific holy grail for scaling is going down to a level where a single atom controls the memory function, and this is what we accomplished in the new study,” says Deji Akinwande, corresponding author of the study.
The team says that the new device is the smallest atomic memory unit ever created. The MoS2 is made into sheets measuring 1 x 1 nanometer and just one atom thick. If it was to be scaled up, it could be used to make chips with storage capacities of around 25 TB per cm2, which is about 100 times higher than current flash memory can provide. It also requires less energy to run.
“The results obtained in this work pave the way for developing future generation applications … such as ultra-dense storage, neuromorphic computing systems, radio-frequency communication systems and more,” says Pani Varanasi, program manager for the US Army Research Office.
The research was published in the journal Nature Nanotechnology.
Source: University of Texas