Angle Selective Piezoelectric Strain Controlled Magnetization Switching in Artificial Spin Ice Based Multiferroic System

Abstract

The prospect of all electrically controlled writing of ferromagnetic bits is highly desirable for developing scalable and energy-efficient spintronics devices. In the present work, we perform micromagnetic simulations to investigate the electric field-induced strain mediated magnetization switching in artificial spin ice (ASI) based multiferroic system, which is proposed to have a significant decrease in Joule heating losses compared to electric current based methods. As the piezo electric strain-based system cannot switch the magnetization by $180^\circ$ in ferromagnets, we propose an ASI multiferroic system consisting of the peanut-shaped nanomagnets on ferroelectric substrate with the angle between the easy axis and hard axis of magnetization less than $90^\circ$. Here the piezoelectric strain-controlled magnetization switching has been studied by applying the electric field pulse at different angles with respect to the axes of the system. Remarkably, magnetization switches by $180^\circ$ only if the external electric field pulse is applied at some specific angles, close to the anisotropy axis of the system ( $\sim 30^\circ - 60^\circ$). Our detailed analysis of the demagnetization energy variation reveals that the energy barrier becomes antisymmetric in such cases, facilitating the complete magnetization reversal. Moreover, we have also proposed a possible magnetization reversal mechanism with two sequential electric field pulses of relatively smaller magnitude. We believe that the present work could pave the way for future ASI-based multiferroic system for scalable magnetic field-free low power spintronics devices.