52 Kの超伝導性は,穴にドーピングされたC60で示されています
1Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974, USA.
Nature
|December 16, 2000
まとめ
研究者は,ゲート誘発ドーピングを使用して,ホールドーピングされたC60フルレンの超伝導性を達成しました. この方法により,ピーク超伝導移行温度 (Tc) が52Kに達し,格子膨張でより高いTc値が可能であることを示唆しました.
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:
- 電子ドーピングされたC60フルレンの超伝導性は,10年前に発見されました.
- ドーパントからC60分子への電子移転は金属状態と超伝導性を誘発する.
- 孔ドーピングされたC60は,バレンスの帯域内の状態の密度が高いため,理論的にはより高い超伝導移行温度 (Tc) を示すことが予測されました.
研究 の 目的:
- 穴にドーピングされたC60.の超伝導性を調査するために.
- 電子ドーピングC60.0と比較してホールドーピングC60でより高いTc値を達成する可能性を調査する.
- ゲート誘発ドーピングがC60.0でホールキャリアを生成する効果を実証する.
主な方法:
- ゲート誘発ドーピングのためのフィールド効果トランジスタ構成を使用した.
- C60フルレネに穴の密度が大きくなった.
- 穴密度の関数として超伝導的移行温度 (Tc) を測定した.
主要な成果:
- 穴の密度の広い範囲で穴ドーピングされたC60で超伝導性が観察されました.
- 超伝導的移行温度 (Tc) は円滑に変化し,最大52Kに達しました.
- C60.0.の穴ドーピングで超伝導性を達成する可能性を実証しました.
結論:
- ゲート誘導ドーピングは,ホール誘導ドーピングC60.0で超伝導性を達成するための効果的な方法です.
- ホールドーピングされたC60で観測された52KのTcは有望である.
- エクストラポレーションにより,Tc値が100Kを超えることは,拡張孔ドープされたC60格子で達成可能であることを示唆しています.
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