基于铁磁/重金属异质结结构的纯自旋流电子器件具有低功耗、非易失性等优点,是当前自旋电子学研究的核心内容.该文利用超导量子干涉仪以及铁磁共振测量系统等手段,对分子束外延法生长的铁磁/重金属异质结Fe3O4/Au单晶薄膜的静态及动态磁性能进行了系统研究.研究表明,随薄膜厚度的增加,Fe3 O4 的单轴磁各向异性逐渐减小而磁晶各向异性逐渐增强.Au覆盖层的引入有助于单晶超薄膜的晶格弛豫,进而有效增强了Fe3 O4 的磁各向异性.该研究为铁磁/重金属异质结的构建提供了新的思路,有望推动其在纯自旋流电子器件中的实用化进程.
Pure spin current devices based on magnetic/heavy metal hetero-structures lie in the core of spintronics due to their advantages of non-volatility and low power consumption.Here the static and dynamic magnetic properties of magnetic/heavy metal hetero-structure of Fe3O4/Au epitaxial thin films prepared by molecular beam epitaxy were systematically investigated by superconducting quantum interference device and ferromagnetic resonance measurements.It has been found that the uniaxial magnetic anisotropy decreases while the cubic magnetocrystalline anisotropy increases with the thickness of the Fe3O4 epitaxial thin films.Moreover,the introduce of heavy metal Au capping layer significantly increases both the uniaxial and cubic magnetic anisotropy in the Fe3O4 films,which may be ascribed to the relaxation of Fe3O4 lattice due to the capping of Au lattice.Therefore,the present work offers an alternative strategy for the fabrication of magnetic/heavy metal hetero-structures,which may promote the practical application of the pure spin current devices in spintronics.