Liang Shixuan, Chen Ruyi, Cui Qirui, Zhou Yongjian, Pan Feng, Yang Hongxin, Song Cheng
Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Nano Lett. 2023 Sep 27;23(18):8690-8696. doi: 10.1021/acs.nanolett.3c02607. Epub 2023 Sep 11.
Conduction electron spins interacting with magnetic impurity spins can mediate an interlayer exchange interaction, namely, the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. This discovery opened the way to significant technological developments in the field of magnetic storage and spintronics. So far, the RKKY-type interlayer interaction has been found to construct symmetric coupling of magnetism; however, the asymmetric counterpart remains unexplored. Here we report unprecedented RKKY-type interlayer Dzyaloshinskii-Moriya interaction (DMI) in synthetic magnets, exhibiting a damped oscillatory feature. This asymmetric interlayer interaction is found to be dramatically dependent on the intermediate coupling layer. By introducing the Fert-Lévy model to the trilayer system, we reveal that the in-plane inversion symmetry breaking plays a pivotal role for generating interlayer DMI and the RKKY oscillation is an intrinsic behavior in metallic multilayers. Our finding fills up the empty block for RKKY-type asymmetric interlayer exchange coupling in comparison to the well-known (symmetric) RKKY-type interlayer exchange coupling.
传导电子自旋与磁性杂质自旋相互作用可介导层间交换相互作用，即鲁德曼 - 基特尔 - 卡苏亚 - 约西达（RKKY）相互作用。这一发现为磁存储和自旋电子学领域的重大技术发展开辟了道路。到目前为止，已发现RKKY型层间相互作用可构建磁的对称耦合；然而，非对称的对应情况仍未得到探索。在此，我们报告了在合成磁体中前所未有的RKKY型层间Dzyaloshinskii - Moriya相互作用（DMI），其呈现出阻尼振荡特征。发现这种非对称层间相互作用极大地依赖于中间耦合层。通过将费尔特 - 列维模型引入三层系统，我们揭示面内反演对称性破缺在产生层间DMI中起关键作用，且RKKY振荡是金属多层膜中的固有行为。与广为人知的（对称的）RKKY型层间交换耦合相比，我们的发现填补了RKKY型非对称层间交换耦合的空白。
