Noncollinear spin state and unusual magnetoresistance in ferrimagnet Co-Gd
Noncollinear spin state and unusual magnetoresistance in ferrimagnet Co-Gd
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亚铁磁体 Co-Gd 中的非共线自旋态和异常磁阻
DOI：
10.1103/physrevmaterials.6.014402
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发表时间：
2022
影响因子：
3.4
通讯作者：
Jianhua Zhao
中科院分区：
文献类型：
--
作者：
Dongdong Chen;Yaohan Xu;Shucheng tong;Wenhui Zheng;Yiming Sun;Jun Lu;Na Lei;Dahai Wei;Jianhua Zhao
稀土过渡金属铁磁材料具有磁矩小、动力学快等优点，有望成为下一代自旋电子器件的候选材料。然而，到目前为止，关于非共线亚铁磁性织构的输运性质的研究还很少。在这项研究中，我们研究了由Co-Gd和铂组成的亚铁磁体/重金属异质结的横向和纵向电阻。根据补偿点附近观察到的非常规磁滞回线，得到了过渡金属亚晶格排列和磁场-温度相图。在共线区域，自旋霍尔磁阻(SMR)和各向异性磁阻(AMR)呈现正常的振荡曲线。在非共线区，由于磁化强度和磁场之间存在90°相移，SMR和AMR信号被反转。由于自旋翻转状态下的锥形自旋织构，当电场垂直于薄膜平面时，会出现尖锐的峰值。我们的结果中的反常磁阻可以用来分析复杂的磁结构，这在非共线自旋电子器件的全电读出中起着重要的作用。
Rare-earth transition-metal ferrimagnetic materials are promising candidates for next-generation spintronic devices owing to their small magnetic moments and fast dynamics. However, only a few studies have been conducted thus far on the transport properties of noncollinear ferrimagnetic spin textures. In this study, we investigate the transverse and longitudinal resistances in a ferrimagnet/heavy-metal heterostructure composed of Co-Gd and Pt. The transition-metal sublattice arrangement and magnetic field–temperature phase diagram are obtained based on unconventional hysteresis loops observed near the compensation point. In the collinear regime, the spin Hall magnetoresistance (SMR) and anisotropic magnetoresistance (AMR) exhibit normal oscillation curves. In the noncollinear regime, the SMR and AMR signals are inverted for the existence of a 90° phase shift between magnetization and magnetic fields. Owing to the conical spin textures in the spin-flop state, sharp peaks emerge when the field is perpendicular to the film plane. The abnormal magnetoresistance in our results can be used to analyze complex magnetic structures, which plays an important role in the all-electrical readout of noncollinear spintronics devices.