According to the team, the new technology provides stable memory at a smaller size than other proposed memory devices.
"Such superconducting memory cells can be scaled down in size to the range of few tens of nanometres, and are not subject to the same performance issues as other proposed solutions," enthused Professor Alexey Bezryadin.
Other devices require ferromagnetic barriers to encode information, whereas the researchers claim the Illinois device does not require any ferromagnetic components and eliminates magnetic-field cross-talk.
"Other efforts to create a scaled-down superconducting memory cell weren't able to reach the scale we have,” added graduate student Andrew Murphy. “A superconducting memory device needs to be cheaper to manufacture than standard memory now, and it needs to be dense, small, and fast."
The device features two superconducting nanowires and two unevenly spaced electrodes which form an asymmetric, closed superconducting loop, called a nanowire superconducting quantum interference device (SQUID).
The memory state is written by applying an oscillating current at a specific magnetic field. To read the memory state, the scientists increased the current to detect the value at which superconductivity gets destroyed.
It turns out that such destruction or critical current is different for the two memory states, ‘0’ or ‘1’. The scientists tested memory stability and found no instances of memory loss.
The researchers argue that this device can operate with a very low dissipation of energy if the energies of two binary states are equal or near equal.
