标题： 铁$_{x}$铬$_{1-x}$中巡游磁性和再入自旋玻璃行为的相互作用 显示英文标题

标题： Interplay of itinerant magnetism and reentrant spin-glass behavior in Fe$_{x}$Cr$_{1-x}$

摘要： 当通过掺杂同结构的巡游铁磁体铁来抑制铬中的巡游反铁磁性时，在铁浓度$x \approx 0.15$处一个假想的量子临界点周围出现自旋玻璃行为的穹顶。 在这里，我们报告了在$0.05 \leq x \leq 0.30$范围内 Fe$_{x}$Cr$_{1-x}$多晶样品的全面研究，使用x射线粉末衍射、磁化率、交流磁化率和中子去极化测量，并补充了$x = 0.15$的比热和电阻率数据。 除了反铁磁性（$x < 0.15$）和铁磁性区域（$0.15 \leq x$）之外，我们在低温度下识别出一个由再进入自旋玻璃行为组成的区域，该区域出现在$0.10 \leq x \leq 0.25$之前有一个前驱现象。中子去极化表明随着$x$和从交流磁化率推断出的 Mydosh 参数$\phi$的增加，铁磁团簇的尺寸增大。综合来看，这些发现一致地将 Fe$_{x}$Cr$_{1-x}$识别为一种巡游电子系统，可以在不变的晶体环境中研究逐渐变化特性的自旋玻璃行为的演变。 显示英文摘要

摘要： When suppressing the itinerant antiferromagnetism in chromium by doping with the isostructual itinerant ferromagnet iron, a dome of spin-glass behavior emerges around a putative quantum critical point at an iron concentration $x \approx 0.15$. Here, we report a comprehensive investigation of polycrystalline samples of Fe$_{x}$Cr$_{1-x}$ in the range $0.05 \leq x \leq 0.30$ using x-ray powder diffraction, magnetization, ac susceptibility, and neutron depolarization measurements, complemented by specific heat and electrical resistivity data for $x = 0.15$. Besides antiferromagnetic ($x < 0.15$) and ferromagnetic regimes ($0.15 \leq x$), we identify a dome of reentrant spin-glass behavior at low temperatures for $0.10 \leq x \leq 0.25$ that is preceded by a precursor phenomenon. Neutron depolarization indicates an increase of the size of ferromagnetic clusters with increasing $x$ and the Mydosh parameter $\phi$, inferred from the ac susceptibility, implies a crossover from cluster-glass to superparamagnetic behavior. Taken together, these findings consistently identify Fe$_{x}$Cr$_{1-x}$ as an itinerant-electron system that permits to study the evolution of spin-glass behavior of gradually varying character in unchanged crystalline environment.