Straintronics: Strain-switched multiferroic nanomagnets for extremely low energy logic/memory

摘要

Straintronics is an extraordinarily energy-efficient novel hardware paradigm for digital computing and signal processing. The central idea is to build the basic binary switch with a nanoscale multiferroic consisting of a magnetostrictive layer elastically coupled to a piezoelectric layer. A tiny voltage of a few mV generates sufficient strain in the piezoelectric layer to switch the magnetization of the magnetostrictive nanomagnet for a memory or logic operation, while dissipating few aJ of energy. Low density processors employing straintronics and operating at slow clock speeds of ～100 MHz are estimated to dissipate such low power that they can run by harvesting energy from the ambient and never even need a battery. We have designed straintronic logic gates and memory cells, and extracted their performance figures with Landau-Lifshitz-Gilbert simulations to predict unprecedented energy efficiency. Rudimentary non-volatile logic and memory functions have been demonstrated experimentally and validate the low energy expectations.