銅酸化物の超伝導体におけるスピン変動と電子のペアリングの間のリンク
K Jin1, N P Butch, K Kirshenbaum
1Center for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USA.
Nature
|August 5, 2011
まとめ
電子ドーピングされた銅酸化物では,温度に直線的に依存する散射率が電子ペアリングと関連していることを研究者は発見しました. これは,スピンの変動がこれらの非常識な超伝導体における線形抵抗性を引き起こすことを示唆している.
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
- 量子材料は,量子的な物質である.
背景:
- 銅酸化物の非常識な超伝導性は,スピン順序やモット断熱器の近さのような議論の余地のある現象を含んでいます.
- 電子ドーピングされた銅酸化物には異常な擬似ギャップがないため,スピンの変動が重要なことを示唆しています.
研究 の 目的:
- La(2-x) Ce(x) CuO(4) 薄膜における磁気輸送を調査する.
- 電子ドーピングされた銅酸化物の異常な正常状態特性におけるスピン変動の役割を決定する.
主な方法:
- La(2-x) Ce(x) CuO(4) の薄膜の磁力輸送測定を行った.
- 温度に依存する散乱速度の分析と,電子ペアリングとの相関.
主要な成果:
- 温度に直線的に依存する散乱速度は,La(2-x) Ce(x) CuO(4) の電子ペアリングと相関する.
- この線形分散は,超伝導性が磁場によって抑制された場合でも持続します.
- この振る舞いは,有機超伝導体で観察されたものを反映している.
結論:
- スピン振動散乱は,電子ドーピングされた銅酸化物における抵抗力の線形温度依存性の原因であると考えられる.
- この発見は,非従来の超伝導性におけるスピン変動の重要性を裏付けている.
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