Magnetic and Mössbauer studies of CaRu 1 − x M x O 3 ( M = Ti and Fe)
Magnetic and Mössbauer studies of CaRu 1 − x M x O 3 ( M = Ti and Fe)
复制标题
CaRu 1 − x M x O 3 (M = Ti 和 Fe) 的磁性和穆斯堡尔研究
DOI：
10.1103/physrevb.66.054418
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发表时间：
2002
影响因子：
3.7
通讯作者：
I. Bradaric
中科院分区：
文献类型：
--
作者：
I. Felner;U. Asaf;I. Nowik;I. Bradaric
${\mathrm{CaRuO}}_{3}$ is a perovskite with an orthorhombic distortion and shows the characteristics of spin-glass behavior below ${T}_{C}=87\mathrm{K}.$ Magnetic studies of polycrystalline ${\mathrm{CaRu}}_{1\ensuremath{-}x}{\mathrm{Ti}}_{x}{\mathrm{O}}_{3}$ $(0lxl0.1)$ reveal that a ferromagnetic transition at ${T}_{C}=34\mathrm{K}$ appears regardless of the nonmagnetic Ti concentration. On the other hand, magnetic and M\"ossbauer effect studies show that ${T}_{C}$ of ${\mathrm{CaRu}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}{\mathrm{O}}_{3}$ (up to $x=0.15)$ is similar to that of pure ${\mathrm{CaRuO}}_{3}:$ however, the Fe induces a ferromagnetic structure. Charge compensation, which is assumed to be present upon ${\mathrm{Fe}}^{3+}$ substitution, induces the appearance of low-spin ${\mathrm{Ru}}^{5+}$ ions, which reduce the paramagnetic moment. Huge magnetic hysteresis loops are observed at 5 K, with coercive fields up to 30 kOe. A second magnetic transition around 250 K is observed for Fe concentrations of $x=0.25$ and 0.35, which is probably caused by Fe-rich clusters. This behavior is consistent with inhomogeneous ferromagnetism found in other perovskite systems.
${\mathrm{CaRuO}}_{3}$ is a perovskite with an orthorhombic distortion and shows the characteristics of spin-glass behavior below ${T}_{C}=87\mathrm{K}.$ Magnetic studies of polycrystalline ${\mathrm{CaRu}}_{1\ensuremath{-}x}{\mathrm{Ti}}_{x}{\mathrm{O}}_{3}$ $(0lxl0.1)$ reveal that a ferromagnetic transition at ${T}_{C}=34\mathrm{K}$ appears regardless of the nonmagnetic Ti concentration. On the other hand, magnetic and M\"ossbauer effect studies show that ${T}_{C}$ of ${\mathrm{CaRu}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}{\mathrm{O}}_{3}$ (up to $x=0.15)$ is similar to that of pure ${\mathrm{CaRuO}}_{3}:$ however, the Fe induces a ferromagnetic structure. Charge compensation, which is assumed to be present upon ${\mathrm{Fe}}^{3+}$ substitution, induces the appearance of low-spin ${\mathrm{Ru}}^{5+}$ ions, which reduce the paramagnetic moment. Huge magnetic hysteresis loops are observed at 5 K, with coercive fields up to 30 kOe. A second magnetic transition around 250 K is observed for Fe concentrations of $x=0.25$ and 0.35, which is probably caused by Fe-rich clusters. This behavior is consistent with inhomogeneous ferromagnetism found in other perovskite systems.