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تسجيل مستخدم جديدGrowth of superconducting epitaxial films of sulfur substituted FeSe via pulsed laser deposition
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We report the successful growth of epitaxial thin films of FeSe$_{1-x}$S$_x$ with $x leq 0.43$ via pulsed laser deposition. As S content increases, the nematic transition temperature, $T_{mathrm s}$, decreases systematically and the superconducting transition temperature, $T_{mathrm c}$, shows a gradual decrease even when $x$ exceeds the nematic end point (NEP), similar to bulk samples. A new kink anomaly was observed in the $rho$-$T$ curves for films with large $x$, which is likely due to a magnetic transition. The obtained phase diagram of FeSe$_{1-x}$S$_x$ thin films is in contrast to that of FeSe$_{1-y}$Te$_y$ films, which shows a rapid increase of $T_{mathrm c}$ at the NEP. Our results demonstrate that the relation between the nematic order and the superconductivity is not universal in the FeSe system, suggesting that the nematic transition does not play a primary role in the superconductivity in these materials.
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