We systematically studied the magnetic and transport properties for thepolycrystalline samples of Fe-doped perovskite cobaltites:Pr$_{1-y}$Ca$_{y}$Co$_{1-x}$Fe$_x$O$_3$ ($y$=0.3, $x$=0-0.15; $y$=0.45,$x$=0-0.3) and Gd$_{0.55}$Sr$_{0.45}$Co$_{1-x}$Fe$_x$O$_{3}$ ($x$=0-0.3). Fedoping leads to an enhancement of the ferromagnetism in the systems ofPr$_{1-y}$Ca$_{y}$Co$_{1-x}$Fe$_x$O$_3$, while the ferromagnetism is suppressedwith further increasing Fe content and spin-glass behavior is observed at highdoping level of Fe. In contrast, the ferromagnetism is suppressed in the systemGd$_{0.55}$Sr$_{0.45}$Co$_{1-x}$Fe$_x$O$_{3}$ as long as Fe is doped, and nospin-glass behavior is observed in the sample with Fe doping up to 0.3. Thecompetition between ferromagnetic interactions throughFe$^{3+}$-O-(LS)Co$^{4+}$ and antiferromagnetic interactions throughFe$^{3+}$-O-Fe$^{3+}$ and Fe$^{3+}$-O-(IS)Co$^{3+}$ is considered to beresponsible for the behavior observed above. The average radius of the ions onA sites plays the key role in determining what type of interactions Fe dopingmainly introduces.
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机译：我们系统地研究了掺杂铁的钙钛矿型钴的多晶样品的磁性和输运性质：Pr $ _ {1-y- $ Ca $ _ {y} $ Co $ _ {1-x} $ Fe $ _x $ O $ _3 $（$ y $ = 0.3，$ x $ = 0-0.15; $ y $ = 0.45，$ x $ = 0-0.3）和Gd $ _ {0.55} $ Sr $ _ {0.45} $ Co $ _ {1 -x} $ Fe $ _x $ O $ _ {3} $（$ x $ = 0-0.3）。 Fedoping导致Pr $ _ {1-y} $ Ca $ _ {y} $ Co $ _ {1-x} $ Fe $ _x $ O $ _3 $系统中的铁磁性增强，而铁磁性被抑制在高掺杂水平下，铁的含量进一步增加，并观察到自旋玻璃的行为。相比之下，只要掺杂了Fe，系统中的铁磁性就会被抑制Gd $ _ {0.55} $ Sr $ _ {0.45} $ Co $ _ {1-x} $ Fe $ _x $ O $ _ {3} $ Fe掺杂量高达0.3时，在样品中观察到无纺丝玻璃的行为。通过Fe $ ^ {3 +} $-O-（LS）Co $ ^ {4 +} $的铁磁相互作用与通过Fe $ ^ {3 +} $-O-Fe $ ^ {3 +} $和Fe的反铁磁相互作用之间的竞争$ ^ {3 +} $-O-（IS）Co $ ^ {3 +} $被认为对上述行为负责。 A位上离子的平均半径在确定Fe掺杂主要引入哪种类型的相互作用中起着关键作用。
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