超伝導的なフィールド効果スイッチ
J H Schon1, C Kloc, R C Haddon
1Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, NJ 07974, USA. Departments of Chemistry and Physics and Advanced Carbon Materials Center, University of Kentucky, Lexington, KY 40506, USA.
Science (New York, N.Y.)
|April 28, 2000
まとめ
科学者たちは,材料を絶縁状態と超伝導状態に切り替える新しいフィールド効果装置を開発しました. このブレークスルーにより,アルカリ金属でドーピングされたC60) の超伝導性が11ケルビンまで可能になった.
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:
- 超伝導性は,物質がゼロの電気抵抗を示す量子力学的現象である.
- 材料の電気的性質を制御し,特に超伝導性を誘導することは,凝縮物質物理学の重要な課題です.
- フーラーレンは,C{60}のように,独自の電子構造により,電子アプリケーションのための有望な材料です.
研究 の 目的:
- 断熱状態と超伝導状態の切り替えのための新しいフィールド効果装置を開発する.
- フィールド効果アプローチを用いて,アルカリ金属ドーピングされたC ((60) の超伝導性を調査する.
- キャリア濃度とC60における超伝導性の関係を調査する.
主な方法:
- 活性物質としてC ((60) を使用したフィールド効果装置の製造.
- 超伝導性の誘導は,アルカリ金属でC (−60) をドーピングすることによって行われる.
- 電気場を適用して,C60の最も上の分子層のキャリア濃度を制御する.
主要な成果:
- 単一の材料で絶縁状態と超伝導状態の切り替えを実証した.
- 11ケルビンまでの温度でアルカリ金属ドーピングされたC ((60) で超伝導性を達成した.
- 活性層のC60) 分子あたり3個の電子を誘導し,超伝導スイッチを作成しました.
結論:
- 開発されたフィールド効果装置は,材料の性質を制御するための新しい方法を提供します.
- このテクニックは,キャリア濃度の関数として超伝導性を研究するための汎用的なプラットフォームを提供します.
- 断熱状態と超伝導状態の切り替え能力は,新しい電子アプリケーションの道を開く.
関連する概念動画
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