超伝導性は,rb/tlで45 kで,コードープされたc60およびc60/c70の混合物です
Science (New York, N.Y.)
|November 8, 1991
まとめ
アルカリ金属・タリウム合金は,フルレン化合物における超伝導的移行温度 (T(c)) を著しく高めます. この研究は,超伝導性においてより高いT (c) 値を達成するための新しいドーピング方法を探求しています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- アルカリ金属でドーピングされたC(60) フラーレンの超伝導性は,高温で発生する.
- 超伝導的移行温度 (T ((c)) の起源と上限を理解することは極めて重要です.
研究 の 目的:
- カリウム・タリウムおよびルビジウム・タリウム合金のC60) /C70) 混合物および純C60) のT (c) への影響を調査する.
- フルレンベースの材料における超伝導的移行温度を増やす方法を探求する.
主な方法:
- ドーピングは,特定の温度範囲 (400~430°C) 内のカリウム・タリウムおよびルビジアム・タリウム合金とのC60) /C70) 混合物および純C60) をドーピングする.
- ドーピングサイト占有率を理解するために,ユニット細胞パラメータの変化を分析する.
主要な成果:
- K-TlおよびRb-Tl合金によるドーピングは,T (c) をそれぞれ25.6Kおよび45K以上に増加させた.
- 純粋なC60) の同様のドーピングは,T60) の増加にもつながった.
- 観察されたより大きな単元細胞のパラメータは,間位点におけるKの部分的置換をTlで示唆しているが,この拡張だけではT (c) の変化を説明できない.
結論:
- アルカリ金属・タリウム合金によるドーピングは,フルレンの超伝導性を強化するための効果的な戦略です.
- 観測されたT (c) の増加は,格子膨張にのみ起因するものではなく,他のメカニズムが作用していることを示唆しています.
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