AI 中文总结
研究通过Cr离子合金化对RuO₂空穴掺杂诱导交替磁性，制备Ru$_{1-x}$Cr$_{x}$O$_{2}$薄膜样品并测量。结果表明反铁磁耦合的铁磁CrO₂团簇共存，Cr离子未使Ru能带空穴掺杂诱导交替磁态，空穴局限于Cr离子。
AI 中文摘要
我们研究了通过与Cr离子合金化对RuO₂进行空穴掺杂以诱导交替磁性的提议。通过反应磁控共溅射在TiO₂衬底上制备了Ru$_{1-x}$Cr$_{x}$O$_{2}$（$0 \leq x \leq 0.28$）薄膜样品，并用X射线衍射验证外延性质，用X射线光电子能谱结合Ar蚀刻确定成分深度分布。低温下对$x = 0$和$x = 0.23$样品的中子衍射测量未显示沿$c$轴或在$ab$平面内自旋的长程交替磁有序证据。相反，$x \geq 0.16$样品的温度依赖磁化率测量显示在$T\approx20$K以下逐渐下降，暗示反铁磁相互作用，尽管对于$x \geq 0.23$样品在4K时这与铁磁滞回和剩余磁化共存。我们的磁力测量和中子散射测量表明反铁磁耦合的铁磁CrO₂团簇共存。这表明Cr离子不会对Ru能带进行空穴掺杂以诱导交替磁态，而是空穴仍局限于Cr离子。
英文摘要
We investigate the proposal of hole doping RuO$_{2}$ via alloying with Cr ions to induce altermagnetism. Thin film samples of Ru$_{1-x}$Cr$_{x}$O$_{2}$ ($0 \leq x \leq 0.28$) were prepared by reactive magnetron co-sputtering on TiO$_{2}$ substrates, with epitaxial nature verified by X-ray diffraction and composition depth profiles determined by X-ray photoelectron spectroscopy combined with Ar etching. Neutron diffraction measurements of samples with $x = 0$ and $x = 0.23$ at low temperatures show no evidence of long-range altermagnetic order with spins oriented along the $c$-axis or within the $ab$-plane. In contrast, temperature dependent susceptibility measurements in samples with $x \geq 0.16$ show a gradual downturn below $T\approx20~$K, suggestive of antiferromagnetic interactions, although this coexists with ferromagnetic hysteresis and remnant magnetization at $4~$K for samples with $x \geq 0.23$. Together, our magnetometry and neutron scattering measurements suggest the coexistence of antiferromagnetically coupled ferromagnetic CrO\textsubscript{2} clusters. This indicates that Cr ions do not hole dope Ru bands to induce an altermagnet state, but rather the holes remain localized to the Cr ions.
