近日，南方科技大学陈朝宇团队研究了层状室温金属交替磁体中的晶体对称配对自旋谷锁定。相关论文于2025年3月31日发表在《自然—物理学》杂志上。
先前的理论研究预测了一种非常规的反铁磁体，其特征是晶体对称性，该对称性在真实空间中连接反铁磁子晶格，同时在互反空间中耦合自旋和动量。这导致了一种独特的晶体对称性配对自旋谷锁定和相关特性，包括压磁和非共线自旋电流，即使没有自旋轨道耦合。然而，大多数已知的非常规反铁磁体不符合非相对论自旋电流的必要对称性要求，这限制了其在自旋电子器件中的应用。
研究组证明了层状室温反铁磁化合物Rb1-δV2Te2O中的晶体对称性配对自旋谷锁定。自旋分辨光电发射测量直接显示了晶体对称配对谷之间的相反自旋分裂。准粒子干涉图显示，由于自旋选择规则是自旋谷锁定的直接结果，因此抑制了谷间散射。这些结果表明，Rb1-δV2Te2O是一种潜在的室温交变磁体候选者。研究组的观察强调了一种方法，该方法既能发挥分层材料的优势，又能通过晶体对称操纵来控制磁性、电子和信息技术的进步。
附：英文原文
Title: Crystal-symmetry-paired spin–valley locking in a layered room-temperature metallic altermagnet candidate
Author: Zhang, Fayuan, Cheng, Xingkai, Yin, Zhouyi, Liu, Changchao, Deng, Liwei, Qiao, Yuxi, Shi, Zheng, Zhang, Shuxuan, Lin, Junhao, Liu, Zhengtai, Ye, Mao, Huang, Yaobo, Meng, Xiangyu, Zhang, Cheng, Okuda, Taichi, Shimada, Kenya, Cui, Shengtao, Zhao, Yue, Cao, Guang-Han, Qiao, Shan, Liu, Junwei, Chen, Chaoyu
Issue&Volume: 2025-03-31
Abstract: Previous theoretical efforts have predicted a type of unconventional antiferromagnet characterized by a crystal symmetry that connects antiferromagnetic sublattices in real space and simultaneously couples spin and momentum in reciprocal space. This results in a unique crystal-symmetry-paired spin–valley locking and related properties including piezomagnetism and non-collinear spin current even without spin–orbit coupling. However, most known unconventional antiferromagnets do not meet the necessary symmetry requirements for non-relativistic spin current, and this limits applications in spintronic devices. Here we demonstrate crystal-symmetry-paired spin–valley locking in a layered room-temperature antiferromagnetic compound, Rb1δV2Te2O. Spin-resolved photoemission measurements directly show the opposite spin splitting between crystal-symmetry-paired valleys. Quasi-particle interference patterns show the suppression of intervalley scattering due to the spin selection rules that are a direct consequence of the spin–valley locking. These results suggest that Rb1δV2Te2O is a potential room-temperature altermagnet candidate. Our observations highlight a methodology that enables both the advantages of layered materials and possible control through crystal symmetry manipulation for advancements in magnetism, electronics and information technology.
DOI: 10.1038/s41567-025-02864-2
Source: https://www.nature.com/articles/s41567-025-02864-2