Abstract SrRuO3 is an orthogonally distorted perovskite (Pbnm) structure whose ferromagnetism is often viewed as an itinerant ferromagnet. Although SrRuO3 has been studied for more than half a century, its structure, magnetism and transport properties are still poorly understood. In this paper, the structure and magnetic evolution of SrRuO3 are discussed in depth through the substitution of Ca2+ for Sr2+ at A sites. The results show that as the Ca substitution increases, the lattice constant decreases, the orthogonal distortion becomes larger, and the saturation magnetization MS, Curie temperature TC and Weiss temperature θp decrease accordingly. Eventually, the ferromagnetic SrRuO3 changes to paramagnetic CaRuO3. The critical exponent β of samples with different substitution contents was obtained by fitting the experimental results, and the value for SrRuO3 (β = 0.55) was similar to that obtained by mean field theory. However, the value increases with the substitution x of Ca, which can't be explained by any scaling theory. The results show that the increase in the value of β is related to the magnetic disorder caused by different magnetic interactions. Analysis using the Rhodes-Wohlfarth criterion indicates that Sr1-xCaxRuO3 has both itinerant-electron and localized-electron magnetism, which is consistent with the theoretical predictions.

中文翻译：

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Ca2+离子取代对SrRuO3结构和磁性的影响：难以捉摸的磁性

摘要 SrRuO3 是一种正交扭曲的钙钛矿 (Pbnm) 结构，其铁磁性通常被视为一种流动的铁磁体。尽管 SrRuO3 已被研究了半个多世纪，但对其结构、磁性和传输特性仍知之甚少。本文通过在A位用Ca2+取代Sr2+来深入讨论SrRuO3的结构和磁性演化。结果表明，随着Ca取代度的增加，晶格常数减小，正交畸变变大，饱和磁化强度MS、居里温度TC和魏斯温度θp相应减小。最终，铁磁性 SrRuO3 变成顺磁性 CaRuO3。对实验结果进行拟合，得到不同取代量样品的临界指数β，SrRuO3 (β = 0.55) 的值与平均场理论获得的值相似。然而，该值随着 Ca 的替代 x 增加，这是任何标度理论都无法解释的。结果表明，β值的增加与不同磁相互作用引起的磁无序有关。使用 Rhodes-Wohlfarth 判据的分析表明 Sr1-xCaxRuO3 具有流动电子和定域电子磁性，这与理论预测一致。