Nanomagnet memory and logic could achieve ultimate energy efficiency
July 6, 2011
The researchers used nanomagnets to build magnetic memory and logic devices about 100 nanometers wide and about 200 nanometers long.
Because they have the same north-south polarity as a bar magnet, the up-or-down orientation of the pole can be used to represent the 0 and 1 of binary computer memory.
When multiple nanomagnets are brought together, their north and south poles interact via dipole-dipole forces to exhibit transistor behavior, allowing simple logic operations.
Such devices would dissipate only 18 millielectron volts of energy per operation at room temperature, the minimum allowed by the second law of thermodynamics, the Landauer limit. That’s 1 million times less energy per operation than consumed by today’s computers, the researchers said.
Ref.: Brian Lambson, David Carlton, Jeffrey Bokor, Exploring the Thermodynamic Limits of Computation in Integrated Systems: Magnetic Memory, Nanomagnetic Logic, and the Landauer Limit, Physical Review Letters, 2011; 107: 010604 [DOI: 10.1103/PhysRevLett.107.010604]