Ferrimagnetic Tb-Fe alloy Thin Films: composition and Thickness Dependence of Magnetic Properties and all-Optical switching
Ferrimagnetic Tb-Fe alloy Thin Films: composition and Thickness Dependence of Magnetic Properties and all-Optical switching
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DOI：
10.3389/fmats.2016.00008
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发表时间：
2016-02-16
影响因子：
3.2
通讯作者：
Albrecht, Manfred
中科院分区：
文献类型：
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作者：
Hebler, Birgit;Hassdenteufel, Alexander;Albrecht, Manfred
铁磁稀土-过渡金属Tb-Fe合金薄膜具有多种不同的磁性能，这些磁性能强烈地依赖于成分和温度。在这项研究中，首先在15和38原子%之间的宽组成范围内研究了膜厚度（5 - 85 nm）对样品磁性能的影响的Tb。从我们的结果中，我们发现Tb-Fe薄膜的补偿点、剩余磁化强度和磁各向异性不仅取决于成分，还取决于磁性薄膜的厚度，临界厚度约为20 - 30 nm。超过这个临界厚度，只有轻微的变化，磁性观察。这种行为可以归因于生长诱导的非晶薄膜的微结构的修改，这影响了短程有序。结果，获得了Tb的分布磁矩沿面外方向沿着与膜厚度的更共线的对准。Tb亚晶格磁化对总样品磁化的这种增加的贡献相当于样品变得更富含Tb，并且可以被称为"有效"组合物。此外，全光开关的可能性，其中Tb-Fe的磁化方向可以被逆转，仅由圆偏振激光脉冲，分析了广泛的组合物和膜厚度，并与底层的磁性。
Ferrimagnetic rare earth - transition metal Tb-Fe alloy thin films exhibit a variety of different magnetic properties, which depend strongly on composition and temperature. In this study, first the influence of the film thickness (5-85 nm) on the sample magnetic properties was investigated in a wide composition range between 15 and 38 at.% of Tb. From our results, we find that the compensation point, remanent magnetization, and magnetic anisotropy of the Tb-Fe films depend not only on the composition but also on the thickness of the magnetic film up to a critical thickness of about 20-30 nm. Beyond this critical thickness, only slight changes in magnetic properties are observed. This behavior can be attributed to a growth-induced modification of the microstructure of the amorphous films, which affects the short range order. As a result, a more collinear alignment of the distributed magnetic moments of Tb along the out-of-plane direction with film thickness is obtained. This increasing contribution of the Tb sublattice magnetization to the total sample magnetization is equivalent to a sample becoming richer in Tb and can be referred to as an "effective" composition. Furthermore, the possibility of all-optical switching, where the magnetization orientation of Tb-Fe can be reversed solely by circularly polarized laser pulses, was analyzed for a broad range of compositions and film thicknesses and correlated to the underlying magnetic properties.