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arXiv · 1007.3980

Self doping effect and successive magnetic transitions in superconducting Sr$_2$VFeAsO$_3$

Guanghan Cao·Zhifeng Ma·Cao Wang·Yunlei Sun·Jinke Bao·Shuai Jiang·Yongkang Luo·Chunmu Feng·Yi Zhou·Zhi Xie·Fengchun Hu·Shiqiang Wei·I. Nowik·I. Felner·Lei Zhang·Zhu'an Xu·Fuchun Zhang
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Abstract

We have studied a quinary Fe-based superconductor Sr$_2$VFeAsO$_3$ by the measurements of x-ray diffraction, x-ray absorption, Mössbauer spectrum, resistivity, magnetization and specific heat. This apparently undoped oxyarsenide is shown to be self doped via electron transfer from the V$^{3+}$ ions. We observed successive magnetic transitions within the VO$_2$ layers: an antiferromagnetic transition at 150 K followed by a weak ferromagnetic transition at 55 K. The spin orderings within the VO$_2$ planes are discussed based on mixed valence of V$^{3+}$ and V$^{4+}$.

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Guanghan Cao, Zhifeng Ma, Cao Wang, Yunlei Sun, Jinke Bao, Shuai Jiang, Yongkang Luo, Chunmu Feng, Yi Zhou, Zhi Xie, Fengchun Hu, Shiqiang Wei, I. Nowik, I. Felner, Lei Zhang, Zhu'an Xu, Fuchun Zhang. 2010-09-27. Self doping effect and successive magnetic transitions in superconducting Sr$_2$VFeAsO$_3$. https://doi.org/10.1103/physrevb.82.104518

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