Sakamoto Shoya, Nomoto Takuya, Higo Tomoya, Hibino Yuki, Yamamoto Tatsuya, Tamaru Shingo, Kotani Yoshinori, Kosaki Hidetoshi, Shiga Masanobu, Nishio-Hamane Daisuke, Nakamura Tetsuya, Nozaki Takayuki, Yakushiji Kay, Arita Ryotaro, Nakatsuji Satoru, Miwa Shinji
The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Japan.
Research Center for Advanced Science and Technology, The University of Tokyo, Meguro, Japan.
Nat Nanotechnol. 2025 Feb;20(2):216-221. doi: 10.1038/s41565-024-01820-0. Epub 2024 Dec 3.
Spintronics based on ferromagnets has enabled the development of microwave oscillators and diodes. To achieve even faster operation, antiferromagnets hold great promise despite their challenging manipulation. So far, controlling antiferromagnetic order with microwave currents remains elusive. Here we induce the coherent rotation of antiferromagnetic spins in a Weyl antiferromagnet W/MnSn epitaxial bilayer by DC spin-orbit torque. We show the efficient coupling of this spin rotation with microwave current. The coupled dynamics produce a DC anomalous Hall voltage through rectification, which we coin the antiferromagnetic spin-torque diode effect. Unlike in ferromagnetic systems, the output voltage shows minimal dependence on frequency because of the stabilization of the precession cone angle by exchange interactions. Between 10 GHz and 30 GHz, the output voltage decreases by only 10%. Numerical simulations further reveal that the rectification signals arise from the fast frequency modulation of chiral spin rotation by microwave spin-orbit torque. These results may help the development of high-speed microwave devices for next-generation telecommunication applications.
基于铁磁体的自旋电子学推动了微波振荡器和二极管的发展。为实现更快的运行速度，反铁磁体尽管其操控具有挑战性，但仍具有巨大潜力。到目前为止，利用微波电流控制反铁磁序仍然难以实现。在此，我们通过直流自旋轨道转矩在Weyl反铁磁体W/MnSn外延双层中诱导反铁磁自旋的相干旋转。我们展示了这种自旋旋转与微波电流的有效耦合。耦合动力学通过整流产生直流反常霍尔电压，我们将其命名为反铁磁自旋转矩二极管效应。与铁磁系统不同，由于交换相互作用使进动锥角稳定，输出电压对频率的依赖性极小。在10吉赫兹至30吉赫兹之间，输出电压仅下降10%。数值模拟进一步揭示，整流信号源于微波自旋轨道转矩对手性自旋旋转的快速频率调制。这些结果可能有助于开发用于下一代电信应用的高速微波器件。
