Researchers from Virginia Commonwealth University created an integrated circuit using spintronics and straintronics. The new IC design uses very little energy - in fact it could run merely by tapping the ambient energy from the environment.
The researchers say that while Spintronics promises very low power switching, when ramped up to usable processing speeds, much of that energy savings is lost because the energy is transferred to the magnet. The new design uses a special class of composite structure called multiferroics (a layer of piezoelectric material with intimate contact to a magnetostrictive nanomagnet). This generates strains in the piezoelectric layer when voltage (even a tiny voltage) is applied - which is then transferred to the magnetostrictive layer. This strain rotates the direction of magnetism, achieving the flip.
The energy dissipated can be as low as 0.4 attojoules, or about a billionth of a billionth of a joule. So this design could create an extremely low-power, yet high-density, non-volatile magnetic logic and memory system. The processors would be well suited for implantable medical devices and could run on energy harvested from the patient's body motion. They also could be incorporated into buoy-mounted computers that would harvest energy from sea waves, among other intriguing possibilities.