六方钡铁氧体薄膜作为邻近工程自旋电子学的可扩展磁绝缘体平台
Barium Hexaferrite Thin Films as a Scalable Magnetic-Insulator Platform for Proximity-Engineered Spintronics
浏览论文内容
中文总结 AI 辅助
本研究确立无需应变工程的溅射生长六方钡铁氧体（BaM）薄膜为具有本征垂直各向异性的可扩展磁绝缘体，可用于邻近工程自旋电子学及拓扑异质结构器件。
中文摘要 AI 辅助
钇铁石榴石（YIG）和铥铁石榴石（TmIG）等稀土铁石榴石是自旋电子学和磁子器件的基准磁绝缘体，但要在这些材料中获得可用的垂直磁各向异性（PMA），通常依赖衬底应变工程，需要严格的晶格匹配和特定的生长条件，这限制了材料的可及性。本文中，我们确立了通过溅射生长的六方钡铁氧体（BaFe₁₂O₁₉，简称BaM）作为一种磁绝缘体替代方案，其具有强本征垂直各向异性，无需应变工程。X射线衍射、透射电子显微镜和拉曼光谱证实，这些薄膜为化学计量比薄膜，表面原子级平整，而第一性原理计算则验证了其稳定的亚铁磁基态。这些薄膜表现出方形的面外磁滞回线，矫顽场接近0.1 T。与稀土石榴石不同，BaM中的垂直各向异性是其磁铅石晶体结构的本征属性，与高度有序的应变无关。当与Pt以及机械剥离的BiSbTeSe₂（简称BSTS）界面结合时，BaM诱导出邻近效应产生的反常霍尔输运，证实了有效的界面交换耦合；而BSTS/BaM异质结构还显示出额外的霍尔贡献，表明存在非共线的界面自旋纹理。这些结果表明，BaM薄膜可作为一种可扩展的磁绝缘体平台，用于突破石榴石化学限制的自旋电子学和拓扑异质结构器件。
英文摘要
Rare-earth iron garnets, such as yttrium iron garnet (YIG) and thulium iron garnet (TmIG), are the benchmark magnetic insulators for spintronic and magnonic devices, but achieving usable perpendicular magnetic anisotropy (PMA) in these materials typically relies on substrate strain- engineering, requiring careful lattice-matching and specific growth conditions that constrain ma- terial accessibility. Here we establish sputter grown barium hexaferrite (BaFe12O19, BaM) as a magnetic-insulator alternative with strong intrinsic perpendicular anisotropy, requiring no strain engineering. X-ray diffraction, transmission electron microscopy and Raman spectroscopy confirm stoichiometric films with atomically smooth surfaces, while first-principles calculations corroborate a robust ferrimagnetic ground state. The films exhibit square out-of-plane hysteresis with a coercive field of nearly 0.1 T. Unlike rare-earth garnets, the perpendicular anisotropy in BaM is intrinsic to its magnetoplumbite crystal structure, arising independent of highly ordered strain. Interfaced with Pt and with exfoliated BiSbTeSe2 (BSTS), BaM induces proximity induced anomalous Hall trans- port, confirming efficient interfacial exchange coupling, while the BSTS/BaM heterostructure shows an additional Hall contribution suggestive of non-collinear interfacial spin textures. These results position BaM thin films as a scalable magnetic-insulator platform for spintronic and topological heterostructure devices beyond the constraints of garnet chemistry.
