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arXiv · 0811.1874

High-pressure growth of fluorine-free SmFeAsO$_{1-x}$ superconducting single crystals

Hyun-Sook Lee·Jae-Hyun Park·Jae-Yeap Lee·Nak-Heon Sung·Ju-Young Kim·B. K. Cho·Tae-Yeong Koo·Chang-Uk Jung·Hu-Jong Lee
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Abstract

Superconducting single crystals of SmFeAsO$_{1-x}$ without fluorine doping were grown at a pressure of 3.3 GPa and a temperature of 1350-1450 $^\circ$C by using the self-flux method. Plate-like single crystals of a few-150 $μ$m in their lateral size were obtained. Single crystals showed the superconducting transition at about 53.5 K with a narrow transition width of 0.5 K. The synchrotron-irradiated x-ray diffractometry patterns and high-angle-annular-dark-field scanning transmission electron microscopy images point to the high quality of the crystals with a well-defined layered tetragonal structure. The chemical compositions of the crystals were estimated by using the electron-probe x-ray microanalysis.

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Hyun-Sook Lee, Jae-Hyun Park, Jae-Yeap Lee, Nak-Heon Sung, Ju-Young Kim, B. K. Cho, Tae-Yeong Koo, Chang-Uk Jung, Hu-Jong Lee. 2008-11-12. High-pressure growth of fluorine-free SmFeAsO$_{1-x}$ superconducting single crystals. https://doi.org/10.1088/0953-2048%2F22%2F7%2F075023

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