Spin superfluid is a novel emerging quantum matter arising from the Bose-Einstein condensate (BEC) of spin-1 bosons. We demonstrate the spin superfluid ground state in canted antiferromagnetic Cr₂O₃ thin film at low temperatures via nonlocal spin transport. A large enhancement of the nonlocal spin signal is observed below ~20 K, and it saturates from ~5 down to 2 K. We show that the spins can propagate over very long distances (~20 μm) in such spin superfluid ground state and that the nonlocal spin signal decreases very slowly as the spacing increases with an inverse relationship, which is consistent with theoretical prediction. Furthermore, spin superfluidity has been investigated in the canted antiferromagnetic phase of the (11[Formula: see text]0)-oriented Cr₂O₃ film, where the magnetic field dependence of the associated critical temperature follows a ²/₃ power law near the critical point. The experimental demonstration of the spin superfluid ground state in canted antiferromagnet will be extremely important for the fundamental physics on the BEC of spin-1 bosons and paves the way for future spin supercurrent devices, such as spin-Josephson junctions.

中文翻译：

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通过非局部自旋输运在倾斜反铁磁体Cr2O3中自旋超流体基态的实验特征。

自旋超流体是一种自旋1玻色子的玻色-爱因斯坦凝聚物（BEC）产生的新型新兴量子物质。我们展示了低温下通过非局部自旋运输在倾斜的反铁磁Cr ₂ O ₃薄膜中的自旋超流体基态。在〜20 K以下观察到非局部自旋信号的大幅增强，并且从〜5下降到2 K饱和。我们证明，在这种自旋超流体基态下，自旋可以传播很长的距离（〜20μm），并且当间隔以反比关系增加时，非局部自旋信号的减小非常缓慢，这与理论预测是一致的。此外，在（11 [式：见正文] 0）取向的Cr ₂的倾斜反铁磁相中研究了自旋超流动性ø ₃膜，其中，所述相关联的临界温度的磁场依存性遵循² / ₃在临界点附近幂定律。倾斜反铁磁体中自旋超流体基态的实验演示对于自旋1玻色子的BEC的基本物理学非常重要，并为将来的自旋超电流器件（如自旋-Josephson结）铺平了道路。