近日，西班牙巴斯克科学基金会Fèlix Casanova团队报道了补偿磁体中破缺时间反演对称性的自旋注入。相关论文于2026年10月28日发表在《自然》杂志上。

自旋流的产生与输运是自旋电子学的核心，这一具有技术相关性的领域利用电子自旋而非仅用电荷来携带和操控信息。传统上，电自旋注入以及电荷流与自旋流的分离，要么依赖于铁磁体（其自旋极化源于净磁化强度），要么依赖于自旋霍尔效应等相对论效应。

研究组证明，可以从Mn₅Si₃——一种净磁化强度为零的补偿磁体——实现自旋注入。利用横向自旋阀器件，研究组以电学方式将自旋从Mn₅Si₃注入非磁性通道，并在空间分离的铁磁电极处检测其传播。在Mn₅Si₃的时间反演磁态之间切换会反转所检测到的自旋信号，表明该自旋注入打破了时间反演对称性。这一行为在两种不同的电偏置几何构型中均被观察到，提供了有别于传统铁磁注入和自旋霍尔注入的特征性信号。

对称性分析、第一性原理计算和自旋输运建模表明，该观测结果与Mn₅Si₃的交错磁序一致；在该磁序中，尽管不存在净磁化强度，仍可产生自旋极化电流。计算给出的自旋极化率为6.5–10%，与传统铁磁体相当；而实验的自旋输运建模表明自旋扩散长度为50–130 nm。该结果为补偿磁体能够产生由其磁序控制的自旋流提供了实验证据，并证明Mn₅Si₃的交错磁性质使其能够在无净磁化强度的情况下实现自旋电子学功能。

附：英文原文

Title: Time-reversal-symmetry-breaking spin injection from a compensated magnet

Author: Mencos, Jone, Badura, Antonin, Dolan, Eoin, Beckert, Sebastian, Gonzlez-Hernndez, Rafael, Sigales, Nicols, Kokkeler, Tim, Kounta, Ismala, Petit, Matthieu, Guillemard, Charles, Hellenes, Anna Birk, Campos, Warlley, Rial, Javier, Kriegner, Dominik, Baltz, Vincent, Hueso, Luis E., Sinova, Jairo, Bergeret, F. Sebastian, Gomonay, Olena, Jungwirth, Tom, mejkal, Libor, Michez, Lisa, Reichlova, Helena, Casanova, Flix

Issue&Volume: 2026-10-28

Abstract: The generation and transport of spin currents are central to spintronics, a technologically relevant field in which information is carried and manipulated using the electron spin rather than solely the electrical charge. Conventionally, electrical spin injection and the separation of charge and spin currents rely either on ferromagnets1,2,3,4,5,6,7,8,9,10, in which spin polarization originates from a net magnetization, or on relativistic effects such as the spin Hall effect11,12,13,14,15,16. Here we demonstrate spin injection from Mn5Si3, a compensated magnet with vanishing net magnetization. Using lateral spin-valve devices, we electrically inject spins from Mn5Si3 into a non-magnetic channel and detect their propagation at a spatially separated ferromagnetic electrode. Switching between time-reversed magnetic states of Mn5Si3 reverses the detected spin signal, demonstrating that the spin injection breaks time-reversal symmetry. This behaviour is observed for two distinct electrical-biasing geometries, providing a characteristic signature that differs from conventional ferromagnetic and spin-Hall injection. Symmetry analysis, first-principles calculations and spin-transport modelling show that our observations are consistent with the altermagnetic order of Mn5Si3, in which spin-polarized currents can arise despite the absence of net magnetization17,18,19,20,21. The calculations yield spin polarizations of 6.5–10%, comparable to those of conventional ferromagnets, whereas the spin-transport modelling of the experiments indicates spin diffusion lengths of 50–130nm. Our results provide experimental evidence that a compensated magnet can generate spin currents controlled by its magnetic order and demonstrate that the altermagnetic properties of Mn5Si3 enable spintronic functionality without net magnetization.

DOI: 10.1038/s41586-026-11227-7

Source: https://www.nature.com/articles/s41586-026-11227-7