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arXiv · 2409.06337

Absence of itinerant ferromagnetism in a cobalt-based oxypnictide

Hua-Xun Li·Hao Jiang·Yi-Qiang Lin·Jia-Xin Li·Shi-Jie Song·Qin-Qing Zhu·Zhi Ren·Guang-Han Cao
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Abstract

We report a layered transition-metal-ordered oxypnictide Sr$_{2}$CrCoAsO$_{3}$. The new material was synthesized by solid-state reactions under vacuum. It has an intergrowth structure with a perovskite-like Sr$_3$Cr$_2$O$_6$ unit and ThCr$_2$Si$_2$-type SrCo$_2$As$_2$ block stacking coherently along the crystallographic $c$ axis. The measurements of electrical resistivity, magnetic susceptibility, and specific heat indicate metallic conductivity from the CoAs layers and short-range antiferromagnetic ordering in the CrO$_{2}$ planes. No itinerant-electron ferromagnetism expected in CoAs layers is observed. This result, combined with the first-principles calculations and the previous reports of other CoAs-layer-based materials, suggests that the Co$-$Co bondlength plays a crucial role in the emergence of itinerant ferromagnetism.

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Hua-Xun Li, Hao Jiang, Yi-Qiang Lin, Jia-Xin Li, Shi-Jie Song, Qin-Qing Zhu, Zhi Ren, Guang-Han Cao. 2024-09-10. Absence of itinerant ferromagnetism in a cobalt-based oxypnictide. https://doi.org/10.1103/physrevmaterials.8.094405

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