鉄カルコゲニドで48ケルビンで再び発生する超伝導性は,
Liling Sun1, Xiao-Jia Chen, Jing Guo
1Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China.
Nature
|February 28, 2012
まとめ
高圧により,鉄カルコゲニドの新たな超伝導相が明らかになる. この段階は,より高い圧力で,超伝導的移行温度 (T (c)) が著しく上昇した状態で再現されます.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
背景:
- 鉄基材料の超伝導性は,圧力によって強く影響されます.
- 化学的代替は圧力効果をシミュレートし,高い超伝導的移行温度 (T (c)) を達成することができます.
- 典型的には,圧力の下でのT (c) は,最適なポイントの後に単調に減少します.
研究 の 目的:
- 典型的な単調な減少を超えて,鉄カルコゲニドの圧力に依存する超伝導的振る舞いを調査する.
- 高圧で新しい超伝導相が出現するかどうかを特定するために.
- この新興相のT (c) を決定する.
主な方法:
- 超伝導鉄カルコゲニドに関する高圧実験.
- 適用された圧力の関数として,超導体移行温度 (T(c)) の測定.
- 特定の材料の分析: Tl{0.6}Rb{0.4}Fe{1.6}Se{2},K{0.8}Fe{1.7}Se{2},K{0.8}Fe{1.7}Se{2}を対象としたものです.
主要な成果:
- 第二の超伝導相が11.5GPa以上で再現することが観察されました.
- この再出現は,最初のT (c) が1GPaで最大32Kから落ちた後に起こった.
- 再現段階は,かなり高いT (c) を示し,48.0〜48.7Kに達しました.
結論:
- 鉄カルコゲニドの圧力誘発超伝導相図は,これまで考えられていたよりも複雑である.
- これらの材料では,高圧で新しい高T (c) 超伝導状態に到達できます.
- この発見は,圧力下での高温超伝導性を探求するための新しい道を開きます.
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