A Noble‐Metal‐Free Spintronic System with Proximity‐Enhanced Ferromagnetic Topological Surface State of FeSi above Room Temperature
A Noble‐Metal‐Free Spintronic System with Proximity‐Enhanced Ferromagnetic Topological Surface State of FeSi above Room Temperature
复制标题
室温以上 FeSi 具有邻近增强铁磁拓扑表面态的无贵金属自旋电子系统
DOI：
10.1002/adma.202206801
复制
发表时间：
2022
影响因子：
29.4
通讯作者：
Tokura Yoshinori
中科院分区：
文献类型：
--
作者：
Hori Tomohiro;Kanazawa Naoya;Hirayama Motoaki;Fujiwara Kohei;Tsukazaki Atsushi;Ichikawa Masakazu;Kawasaki Masashi;Tokura Yoshinori
金属界面、拓扑绝缘体和二维材料的强自旋轨道耦合态能够有效地控制自旋态，为自旋电子学提供了巨大的潜力。然而，仍有材料方面的挑战需要克服，包括集成到先进的硅电子器件中，以及这些材料中构成重元素的稀缺资源。通过磁输运测量和第一性原理计算，本文证明了FeSi中自旋轨道耦合（SOC）诱导的铁磁拓扑表面态的鲁棒性及其通过与邻近材料杂化的可控性。与自然氧化表面相比，铁磁转变温度大大高于室温，在靠近宽禁带氟化物绝缘体的表面，有效SOC强度几乎增加了一倍。这些增强的磁性可以实现室温磁化开关，适用于基于自旋轨道扭矩的自旋电子器件。在无贵金属硅基化合物中实现强SOC将加速自旋电子的应用。
Strongly spin–orbit coupled states at metal interfaces, topological insulators, and 2D materials enable efficient electric control of spin states, offering great potential for spintronics. However, there are still materials challenges to overcome, including the integration into advanced silicon electronics and the scarce resources of constituent heavy elements of those materials. Through magneto‐transport measurements and first‐principles calculations, here robust spin–orbit coupling (SOC)‐induced properties of a ferromagnetic topological surface state in FeSi and their controllability via hybridization with adjacent materials are demonstrated. In comparison to the case of its naturally oxidized surface, the ferromagnetic transition temperature is greatly increased beyond room temperature and the effective SOC strength is almost doubled at the surface in proximity to a wide‐bandgap fluoride insulator. Those enhanced magnetic properties enable room‐temperature magnetization switching, being applicable to spin–orbit torque based spintronic devices. Realization of strong SOC in the noble‐metal‐free silicon‐based compound will accelerate spintronic applications.