Virginia Commonwealth University (VCU) researchers have developed a unique integrated circuit by coalescing two cutting-edge technologies that include straintronics and spintronics.
The design suggested requires negligible amount of energy making batteries unnecessary. It is capable of operating with the help of environmental ambient energy. Contrary to the traditional electronic switches that are charge-based and encoded with 0s and 1s, spintronics uses the natural spin of electrons either upwards or downwards for storing bits of information. Spinning in one direction gives a 0 and switching the spin to the opposite direction by inducing spin-polarized current pulse or a magnetic field gives a 1.
Spintronics uses insignificant amount of energy during the switching process when compared to charge-based electronics. However, when increased to normal processing speeds, much of the saved energy gets wasted in the mechanism that enables environmental energy to be transmitted to the magnet. The solution utilizes a unique group of composite structure known as multiferroics. These structures comprise a piezoelectric material layer with close contact to a magnetostrictive nanomagnet. The nanomagnet shows a shape modification when subjected to strain. On applying a minute voltage across the structure, strain is generated in the piezoelectric material layer, which is later transmitted to the magnetostrictive layer. This strain leads to rotation of the magnetism direction, thereby attaining a flip. By making a correct materials choice, the degenerated energy could be low equivalent to several billionth of a billionth of a joule or 0.4 aJ. This design will result in a non-volatile magnetic memory and logic system with very low-power and high-density. The processors will be ideal for implantable medical devices and can be operated using the energy derived from the patient's body movement. In addition, they can be integrated into buoy-mounted computers capable of deriving energy from sea waves, which is one among several interesting possibilities.