A Critical Analysis of the Feasibility of Pure Strain-Actuated Giant Magnetostrictive Nanoscale Memories

TL;DR

This paper critically examines the practicality of stress-induced magnetostrictive nanomemory devices, highlighting the impact of material damping, anisotropy, and thermal effects on their feasibility and design.

Contribution

It provides a comprehensive analysis of the material and physical constraints affecting the implementation of stress-actuated nanomagnetic memories.

Findings

High Gilbert damping challenges toggle-mode switching feasibility.

Material anisotropy and demagnetization energies are critical for switching success.

Thermal stability significantly influences device viability and design.

Abstract

Concepts for memories based on the manipulation of giant magnetostrictive nanomagnets by stress pulses have garnered recent attention due to their potential for ultra-low energy operation in the high storage density limit. Here we discuss the feasibility of making such memories in light of the fact that the Gilbert damping of such materials is typically quite high. We report the results of numerical simulations for several classes of toggle precessional and non-toggle dissipative magnetoelastic switching modes. Material candidates for each of the several classes are analyzed and forms for the anisotropy energy density and ranges of material parameters appropriate for each material class are employed. Our study indicates that the Gilbert damping as well as the anisotropy and demagnetization energies are all crucial for determining the feasibility of magnetoelastic toggle-mode precessional switching schemes. The roles of thermal stability and thermal fluctuations for stress-pulse switching of giant magnetostrictive nanomagnets are also discussed in detail and are shown to be important in the viability, design, and footprint of magnetostrictive switching schemes.