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arXiv 2303.16615cond-mat.str-el
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Cr取代焦绿石铱酸盐 $Y_2Ir_2O_7$ 中类 Griffiths 相及其演化的识别

Identification of Griffiths-like phase and its evolution in Cr substituted pyrochlore iridates $Y_2Ir_2O_7$

Vinod Kumar Dwivedi

AI总结:

该研究在 Cr 取代的 $Y_2Ir_2O_7$ 焦绿石铱酸盐中识别出随取代增强的类 Griffiths 相和团簇玻璃态,并将其归因于多种自旋耦合竞争及 RKKY 类相互作用。

摘要:

我们报道了在几何阻挫反铁磁 Cr 取代的 $Y_2Ir_2O_7$ 焦绿石铱酸盐中存在 Griffiths 相(GP)类状态以及团簇玻璃类状态。GP 类行为的强度随取代量增加而增强。有趣的是,等温剩磁表明 GP 区域内自旋具有类 Ising 相互作用。GP 类状态不能归因于结构无序,因为 Cr 取代并未引起任何结构变化。随后,$Cr^{3+} \leftrightarrow Cr^{3+}$、$Ir^{4+} \leftrightarrow Ir^{4+}$、$Ir^{4+} \leftrightarrow Cr^{3+}$ 以及 $Ir^{4+} \leftrightarrow Ir^{5+}$ 之间的自旋耦合导致反铁磁关联与铁磁关联之间的竞争。这使 $Cr^{3+}$ 局域磁矩之间产生由巡游 Ir 传导电子介导的 Ruderman-Kittel-Kasuya-Yosida(RKKY)类相互作用,因此 GP 和团簇玻璃类状态随之出现。

英文摘要:

We report the Griffiths phase (GP)-like state along with cluster-glass-like state in geometrically frustrated antiferromagnetic $Cr$ substituted $Y_2Ir_2O_7$ pyrochlore iridates. The strength of GP-like behaviour increases with substitution. Interestingly, isothermal remanent magnetization suggests the Ising-like interaction of spins in GP region. The GP-like state is not attributed to the structural disorder as substitution of Cr does not induces any structural change. Then the spin coupling between $Cr^{3+} \leftrightarrow Cr^{3+}$, $Ir^{4+} \leftrightarrow Ir^{4+}$, $Ir^{4+} \leftrightarrow Cr^{3+}$ and $Ir^{4+} \leftrightarrow Ir^{5+}$ leads the competition between antiferromagnetic and ferromagnetic correlations. It give rise to Ruderman-Kittel-Kasuya-Yosida (RKKY)-like interaction between $Cr^{3+}$ local magnetic moments mediated by itinerant $Ir$ conduction electrons, hence, as a result GP and cluster-glass-like states emerges.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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