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We propose a heterostructure device comprised of magnets and piezoelectrics, which significantly improves the delay and the energy dissipation of an all-spin logic (ASL) device. This paper studies and models the physics of the device, illustrates its operation, and benchmarks its performance using SPICE simulations. We show that the proposed device maintains low-voltage operation, nonreciprocity, nonvolatility, cascadability, and thermal reliability of the original ASL device. Moreover, by utilizing the deterministic switching of a magnet from the saddle point of the energy profile, the device is more efficient in terms of energy and delay and is robust to thermal fluctuations. The results of simulations show that compared to ASL devices, the proposed device achieves $21\times $ shorter delay and $27\times $ lower energy dissipation per bit for a 32-bit arithmetic-logic unit. [ABSTRACT FROM AUTHOR]

Recent experiments have shown the ability to introduce an anisotropy energy to the energy landscape of a thin-film nanomagnet through the use of mechanical strain. Assuming this strain-induced anisotropy is large enough, the low-energy state of the nanomagnet is altered and can be used to initialize the magnetization along a given axis. Utilizing this effect, we propose a more energy efficient method of nanomagnet reversal through spin-transfer torque (STT). This is accomplished by first initializing the magnetization to a high-energy state and then applying a short current pulse to nudge the magnetization in the appropriate energy basin. Using extensive numerical simulations, we qualitatively analyze this type of reversal and find the optimal parameters for reliable functionality while in the presence of thermal noise. We demonstrate that despite negating the initial portion of nominal STT reversal, where the STT must fight against the damping torque of the initial energy-basin, the magnitude of spin current required for our proposed strain-mediated reversal is equivalent to the nominal case. However, the strain-meditated reversal is beneficial by minimizing the spin-current pulsewidth necessary for reliable operation allowing for large energy savings. Assuming the strain-anisotropy is significantly larger than the nanomagnet’s internal free-axis anisotropy, strain-mediated reversals offer a 10 \times energy reduction over nominal STT reversals. [ABSTRACT FROM AUTHOR]