Deng Sihao, Gomonay Olena, Chen Jie, Fischer Gerda, He Lunhua, Wang Cong, Huang Qingzhen, Shen Feiran, Tan Zhijian, Zhou Rui, Hu Ze, Šmejkal Libor, Sinova Jairo, Wernsdorfer Wolfgang, Sürgers Christoph
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, 76049, Germany.
Nat Commun. 2024 Jan 27;15(1):822. doi: 10.1038/s41467-024-45129-x.
Resistivity measurements are widely exploited to uncover electronic excitations and phase transitions in metallic solids. While single crystals are preferably studied to explore crystalline anisotropies, these usually cancel out in polycrystalline materials. Here we show that in polycrystalline MnZnGeN with non-collinear antiferromagnetic order, changes in the diagonal and, rather unexpected, off-diagonal components of the resistivity tensor occur at low temperatures indicating subtle transitions between magnetic phases of different symmetry. This is supported by neutron scattering and explained within a phenomenological model which suggests that the phase transitions in magnetic field are associated with field induced topological orbital momenta. The fact that we observe transitions between spin phases in a polycrystal, where effects of crystalline anisotropy are cancelled suggests that they are only controlled by exchange interactions. The observation of an off-diagonal resistivity extends the possibilities for realising antiferromagnetic spintronics with polycrystalline materials.
电阻率测量被广泛用于揭示金属固体中的电子激发和相变。虽然单晶更适合用于探索晶体各向异性，但这些通常在多晶材料中会相互抵消。在此，我们表明，在具有非共线反铁磁序的多晶MnZnGeN中，电阻率张量的对角分量以及相当意外的非对角分量在低温下发生变化，这表明不同对称性的磁相之间存在微妙的转变。这得到了中子散射的支持，并在一个唯象模型中得到了解释，该模型表明磁场中的相变与场诱导的拓扑轨道动量有关。我们在多晶体中观察到自旋相之间的转变，其中晶体各向异性的影响被抵消，这一事实表明它们仅由交换相互作用控制。非对角电阻率的观测扩展了用多晶材料实现反铁磁自旋电子学的可能性。
