Topologically non-trivial electronic structures can give rise to a range of unusual physical phenomena, and the interplay of band topology with other effects such as electronic correlations and magnetism requires further exploration. The rare earth monopnictides X(Sb,Bi) (X = lanthanide) are a large family of semimetals where these different effects may be tuned by the substitution of rare-earth elements. Here we observe anomalous behavior in the quantum oscillations of one member of this family, antiferromagnetic SmSb. The analysis of Shubnikov-de Haas (SdH) oscillations provides evidence for a non-zero Berry phase, indicating a non-trivial topology of the α-band. Furthermore, striking differences are found between the temperature dependence of the amplitudes of de Haas-van Alphen effect oscillations, which are well fitted by the Lifshitz-Kosevich (LK) formula across the measured temperature range, and those from SdH measurements which show a significant disagreement with LK behavior at low temperatures. Our findings of unusual quantum oscillations in an antiferromagnetic, mixed valence semimetal with a possible non-trivial band topology can provide an opportunity for studying the interplay between topology, electronic correlations and magnetism.

拓扑非平凡的电子结构会引起一系列异常的物理现象，并且能带拓扑与其他效应（如电子相关性和磁性）的相互作用也需要进一步探索。稀土单素X（Sb，Bi）（X  =镧系元素）是一大类半金属，可以通过稀土元素的替代来调节这些不同的作用。在这里，我们观察到该族中一个成员反铁磁SmSb的量子振荡中的反常行为。Shubnikov-de Haas（SdH）振荡的分析为非零Berry相位提供了证据，表明α的非平凡拓扑-乐队。此外，发现德哈斯-范·阿尔芬效应振荡的幅度的温度依赖性与Ldshitz-Kosevich（LK）公式在所测温度范围内完全吻合，而SdH测量结果显示出显着差异，两者之间存在显着差异。与低温下的LK行为不同。我们在反铁磁，混合价半金属中可能具有非平凡的带形拓扑结构中异常量子振荡的发现，可以为研究拓扑结构，电子相关性和磁性之间的相互作用提供机会。