标题： IV型二维共线磁体中的异常霍尔效应 显示英文标题

标题： Anomalous Hall Effect in Type IV 2D Collinear Magnets

摘要： 我们识别出一类之前未被认识到的二维（2D）共线磁性相，该类相超出了铁磁体、反铁磁体和交替磁体等已建立的类别。 这些第四类二维共线磁体在非相对论极限下表现出自旋简并带，但在零净磁化的情况下仍支持打破时间反演对称性的响应，例如异常霍尔效应（AHE）。 基于自旋层群分析，我们推导了该相的对称性标准，并通过第一性原理计算从二维数据库中筛选可行的候选材料。 以单层Hf₂S为例，我们证明在没有自旋轨道耦合的情况下，能带是自旋简并的，而其存在会诱导由自旋极化甚至自旋中性电流驱动的AHE，并伴随着对称保护的真正全空间持续自旋纹理。 这些发现扩展了磁性相的分类，并拓宽了实现二维非常规自旋电子功能的途径。 显示英文摘要

摘要： We identify a previously unrecognized class of two-dimensional (2D) collinear magnetic phase that extends beyond the established categories of ferromagnets, antiferromagnets, and altermagnets. These type IV 2D collinear magnets exhibit spin-degenerate bands in the nonrelativistic limit, yet support time-reversal symmetry-breaking responses, such as the anomalous Hall effect (AHE), despite having zero net magnetization. Based on spin layer group analysis, we derive the symmetry criteria for this phase and perform first-principles calculations to screen viable candidate materials from 2D databases. Using monolayer Hf2S as a prototype, we demonstrate that in the absence of spin-orbit coupling, the bands are spin degenerate, while its inclusion induce an AHE driven by spin-polarized and even spin-neutral currents, accompanied by a symmetry-protected, truly full-space persistent spin texture. These findings expand the classification of magnetic phases and broaden avenues for realizing unconventional spintronic functionalities in two dimensions.