标题： 反磁性RuO₂薄膜中的自旋分裂磁阻 显示英文标题

标题： Spin-Splitting Magnetoresistance in Altermagnetic RuO2 Thin Films

摘要： 最近发现的反磁体（altermagnets），以其磁交换相互作用与交替晶体环境的奇特关联为特征，为自旋电子学提供了令人兴奋的前沿机会。然而，作为最早发现的反磁体之一的RuO2的反磁性目前正受到激烈的争论。 在这里，我们尝试通过展示一种由与反磁体巨大的非相对论自旋分裂相关的自旋电流驱动的反磁性自旋分裂磁阻（SSMR）效应来解决这一争议。与由常规相对论自旋流引起的自旋霍尔磁阻相比，SSMR具有独特的角度依赖性，并且其相位偏移特性是由奈尔矢量的方向决定的，同时由于其对电子散射的敏感性，还表现出显著的温度依赖性。 通过对（101）-RuO2/Co双层膜磁阻的系统研究，我们分离出一个相当大的SSMR，从而揭示了沿[001]方向的奈尔矢量。我们的工作不仅展示了探测反磁体奈尔矢量的一种简单的电途径，而且还表明RuO2薄膜中存在长程磁有序。 显示英文摘要

摘要： The recently discovered altermagnets, featured by the exotic correlation of magnetic exchange interaction and alternating crystal environments, have offered exciting cutting-edge opportunities for spintronics. Nevertheless, the altermagnetism of RuO2, one of the earliest-discovered altermagnets, is currently under intense debate. Here we try to resolve this controversy by demonstrating an altermagnetic spin-splitting magnetoresistance (SSMR) effect that is driven by a spin current associated with the giant nonrelativistic spin splitting of an altermagnet. Compared to the spin Hall magnetoresistance induced by a conventional relativistic spin current, the SSMR is characterized by unusual angular dependence with a phase-shift feature underpinned by the Neel-vector orientation and pronounced temperature dependence caused by its susceptibility to electron scattering. Through systematical investigations on the magnetoresistance of (101)-RuO2/Co bilayers, we disentangle a sizable SSMR and hence unveil a Neel vector along [001] direction. Our work not only demonstrates a simple electric avenue to probing the Neel vector of altermagnets, but also indicates long-range magnetic order in thin films of RuO2.