论文标题
稳定的界面铁磁剂和用重型过渡金属TA覆盖的超薄FERH膜的磁电特性增强
Stabilized Interfacial Ferromagnetism and Enhanced Magnetoelectric Properties of Ultrathin FeRh Films Capped with Heavy Transition Metal Ta
论文作者
论文摘要
最近对薄的Ferh膜进行了广泛的研究，并在实验中广泛观察到了新出现的底物和限制依赖性界面的界面铁磁（FM）。但是，几乎没有研究这种界面铁磁磁性的电压调制，这将在基于抗铁磁的（AFM）基于FERH的磁电磁性随机访问记忆（MERAM）中具有深刻的应用。我们使用从头算技术，相对研究了由重型过渡金属TA覆盖的超薄Ferh膜的界面铁磁特性和磁电响应。我们发现，TA盖倒流会逆转超薄Ferh膜的相位稳定性以下1.5 nm，并显着稳定铁磁相和界面的铁磁性。此外，不管磁性构型和膜厚度如何。与FERH/MGO双层相比，磁各向异性（AFM的平面内，FM的垂直线和界面-FM重建的三层型）以及这些三层层的磁电响应得到了增强。此外，FM阶段中的VCMA行为从$ \ vee $形状更改为线性。这些发现证明了用重金属封盖和电场对FERH薄膜进行磁性顺序的操纵，并可以促进FERH合金在磁记忆和抗磁性旋转旋转中的应用。
Thin FeRh film was extensively studied recently, and an emergent substrate- and capping-dependent interfacial ferromagnetism (FM) was widely observed in experiments. However, the voltage modulation of this interfacial ferromagnetism is barely studied, which would have profound applications in antiferromagnetic (AFM) FeRh-based magnetoelectric-random access memory (MeRAM). Using ab initio techniques, we comparatively study the interfacial ferromagnetic properties and magnetoelectric responses of ultrathin FeRh films capped by heavy transition metal Ta. We find that Ta capping reverses the phase stability of ultrathin FeRh film below 1.5 nm and gigantically stabilizes the ferromagnetic phase and interfacial ferromagnetism. Besides, small magnetic moment of 2.2 $μ_B$ for neighboring Fe atoms, regardless of magnetic configurations and film thickness, is induced by Ta capping. Compared with FeRh/MgO bilayers, magnetic anisotropies (in-plane for AFM, perpendicular for FM and interfacial-FM reconstructed trilayers) and magnetoelectric responses of these trilayers are enhanced. Furthermore, the VCMA behavior in FM phase is changed from $\vee$-shaped to linear. These findings demonstrate the manipulation of magnetic ordering of FeRh films with heavy metal capping and electric field and can promote the application of FeRh alloy in magnetic memory and antiferromagnetic spintronics.
