Electrons in metals can show a giant anomalous Hall effect (AHE) when interacting with characteristic spin texture. The AHE has been discussed in terms of scalar-spin-chirality (SSC) in long-range-ordered noncollinear spin textures typified by Skyrmion. The SSC becomes effective even in the paramagnetic state with thermal fluctuations, but the resultant AHE has been limited to be very small. Here, we report the observation of large AHE caused by the spin fluctuation near the devil’s staircase transition in a collinear antiferromagnetic metal SrCo₆O₁₁. The AHE is prominent near and above the transition temperature at moderate magnetic fields, where the anomalous Hall angle becomes the highest level among known oxide collinear ferromagnets/antiferromagnets (>2%). Furthermore, the anomalous Hall conductivity is quadratically scaled to the conductivity. These results imply that the thermally induced solitonic spin defects inherent to the devil’s staircase transition promote SSC-induced skew scattering.

金属中的电子在与特征自旋结构相互作用时会表现出巨大的反常霍尔效应（AHE）。 AHE 已经根据以 Skyrmion 为代表的长程有序非共线自旋纹理中的标量自旋手性 (SSC) 进行了讨论。即使在具有热波动的顺磁状态下，SSC 也会变得有效，但所得的 AHE 仅限于非常小。在这里，我们报告了在共线反铁磁金属 SrCo ₆ O ₁₁中由魔鬼阶梯跃迁附近的自旋涨落引起的大 AHE 的观察。在中等磁场下，AHE 在接近和高于转变温度时非常突出，其中反常霍尔角成为已知氧化物共线铁磁体/反铁磁体中的最高水平（>2%）。此外，反常霍尔电导率与电导率成二次方关系。这些结果意味着魔鬼阶梯跃迁固有的热致孤子自旋缺陷促进了 SSC 引起的斜散射。