微纳尺度多铁异质结中电驱动磁反转

近年来,多铁异质结中电控磁性研究引起了广泛关注,已成为多铁领域的热点.现代自旋电子学器件(如磁内存)通常利用电流产生的磁场或自旋转移扭矩效应驱动磁反转来实现数据擦写,但这带来高额能耗和热量,成为亟待解决的关键难题.而利用多铁异质结实施电场驱动磁反转则有望大幅降低能耗,从而实现高速、低能耗、高稳定性新型高密度磁存储、逻辑及其他自旋电子学器件.在当前器件发展的微型化趋势下,探索可集成化的微纳尺度电场驱动磁反转方案显得越发重要.本文针对发展新型磁电器件所面临的微型化关键问题,回顾了微纳尺度电场驱动磁反转研究的新进展,主要关注小尺度多铁异质结中电控磁的新特点、新方法及相关物理机理的实验和理论成果,讨论了进入纳米尺度将面临的挑战,并对未来研究工作提出一些展望.

Electric field driven magnetic switching in nanoscale multiferroic heterostructures

Recently, there has been a surge of research interest in the electric field control of magnetism due to its promising application in spintronic and memory devices, which has become a hot topic in the field of multiferroic research. In current spintronic technology, magnetic reversal is usually driven by a large electric current via current generated magnetic field or spin-torque effect to write/erase a magnetic bit, and thus producing large power consumption and heat dissipation. While using insulating multiferroic materials, the reversal of magnetization can be triggered by applying an electric field instead of current, hence dramatically reducing the energy consumption and heat dissipation. With the current miniature trend in microelectronic technology, it is very essential to explore the electric field driven magnetic reversal (EFMS) behaviours in a micro/nanometer scale. In this article we briefly review the new progress in the field of EFMS based on multiferroic heterostructures, including some new features arising from size reduction, as well as some recent experimental and theoretical advances towards nanoscale EFMS, e.g. strain-mediated coupling, or spin exchange coupling in BiFeO₃-based heterostructures, and their associated mechanisms. Finally, some key challenges in developing future EFMS based magnetoelectric devices, and some prospects for future research are also discussed.