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arXiv · 0812.2091

Evidence for Coexistence of Superconductivity and Magnetism in Single Crystals of Co-doped SrFe$_2$As$_2$

Jun Sung Kim·Seunghyun Khim·Liqin Yan·N. Manivannan·Yong Liu·Ingyu Kim·G. R. Stewart·Kee Hoon Kim
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Abstract

In order to investigate whether magnetism and superconductivity coexist in Co-doped SrFe$_2$As$_2$, we have prepared single crystals of SrFe$_{2-x}$Co$_x$As$_2$, $x$ = 0 and 0.4, and characterized them via X-ray diffraction, electrical resistivity in zero and applied field up to 9 T as well as at ambient and applied pressure up to 1.6 GPa, and magnetic susceptibility. At $x$ = 0.4, there is both magnetic and resistive evidence for a spin density wave transition at 120 K, while $T_c$ = 19.5 K - indicating coexistent magnetism and superconductivity. A discussion of how these results compare with reported results, both in SrFe$_{2-x}$Co$_x$As$_2$ and in other doped 122 compounds, is given.

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Jun Sung Kim, Seunghyun Khim, Liqin Yan, N. Manivannan, Yong Liu, Ingyu Kim, G. R. Stewart, Kee Hoon Kim. 2008-12-11. Evidence for Coexistence of Superconductivity and Magnetism in Single Crystals of Co-doped SrFe$_2$As$_2$. https://doi.org/10.1088/0953-8984%2F21%2F10%2F102203

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