We demonstrate observation of the angular momentum compensation temperature T_A, at which the net angular momentum is quenched in ferrimagnets. Using the Barnett effect, in which an object is magnetized by mechanical rotation owing to spin–rotation coupling, we measure T_A in the Ho_3−xDy_xFe₅O₁₂ system. We determine T_A to be 240 K in Ho₃Fe₅O₁₂ (HoIG). We find that T_A increases with Dy content and show that T_A of Ho_1.5Dy_1.5Fe₅O₁₂ corresponds with room temperature. We also demonstrate that ⁵⁷Fe-NMR measurements can be applied to explore domain wall dynamics in HoIG. We find that the NMR intensity exhibits a maximum at T_A in the multi-domain state. We provide a simple model for describing this NMR signal enhancement caused by enhancement of domain-wall mobility at T_A.

中文翻译：

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通过巴尼特效应和核磁共振观察角动量补偿

我们展示了角动量补偿温度T _{A 的}观察结果，在该温度下，亚铁磁体中的净角动量被淬灭。使用 Barnett 效应，其中物体由于自旋-旋转耦合而被机械旋转磁化，我们在 Ho _{3− x} Dy _x Fe ₅ O ₁₂系统中测量T _A。我们在 Ho ₃ Fe ₅ O ₁₂ (HoIG) 中确定T _A为 240 K。我们发现T _A随着 Dy 含量_的增加而增加，并表明Ho _1.5 Dy 的T _A1.5 Fe ₅ O ₁₂对应于室温。我们还证明了⁵⁷ Fe-NMR 测量可用于探索 HoIG 中的畴壁动力学。我们发现 NMR 强度在多域状态下在T _A处表现出最大值。我们提供了一个简单的模型来描述由T _A的畴壁迁移率增强引起的这种 NMR 信号增强。