(Ba1-xYbx)Fe2As2 單晶樣品的製作與超導性質研究

Preparation and superconductivity in (Ba1-xYbx)Fe2As2 single crystals

陳善儉(Shan-Chien Chen)

指導教授 ： 李文新

國立中正大學/理學院/物理學系/博士(2015年)

摘要

我們製作Yb取代BaFe2As2中的Ba的單晶，發現具有超導性質，單晶樣品製作是使用自助熔法(Self-flux)及慢速冷卻製作(Ba1-xYbx)Fe2As2 單晶，X光繞射數據資料顯示樣品屬於ThCr2Si2結構。並且以Yb取代後c軸晶格常數隨取代量提升而減少。磁性量測顯示(Ba1-xYbx)Fe2As2取代量在0.5 ≦ x ≦ 1.5之間時，具有極明顯的順磁與超導反磁的相轉換，其超導臨界溫度TC在18 ~ 20 K。

關鍵字

镱取代稀土元素 ； 鐵砷層 ； 鐵基超導體

並列摘要

We report the discovery of superconductivity in Yb-doped BaFe2As2. Single-crystal specimens of (Ba1-xYbx)Fe2As2 were grown by using FeAs flux and slow-cooling method. All the grown crystals were found to have pure tetragonal ThCr2Si2-type structure by X-ray diffraction spectrum. The lattice parameter c decreases as the Yb substitution increases. A clear phase transition from paramagnetic to perfect diamagnetic state was observed around 18~20 K for the samples with nominal composition.

並列關鍵字

FeAs layer ； iron-based superconductor ； Yb doped

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