(Y,Nd) Ba2Cu3O ((6+x)) の長距離不相応の電荷変動について

G Ghiringhelli¹, M Le Tacon, M Minola

¹CNR-SPIN, Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, and Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy. giacomo.ghiringhelli@fisi.polimi.it

Science (New York, N.Y.)

|July 17, 2012

まとめ

研究者らは,共振軟X線散射を用いたコプラート超伝導体における競合する電荷変動の証拠を発見した. これらの変動は,超伝導性と競合する初期電荷密度波の不安定性を示している.

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

背景:

カップレート材料の超伝導性は,他の電子秩序と競合することが知られている.
大量に敏感な探査機を用いたこれらの競合する注文に対する直接的な実験的証拠は依然として困難である.

研究の目的:

カップレート超伝導体の競合する電子注文を特定し,特徴づけること.
充電変動と超伝導性の関係を調査する.

主な方法:

振動性柔らかいX線散射は,電荷の変動を検出するために使用されました.
この研究は,異なる穴の濃度を持つ (Y,Nd) Ba(2) Cu(3) O(6+) ((x) 超伝導体に焦点を当てた.

主要な成果:

不相応な周期性を持つ二次元電荷の変動は,銅酸化物平面で特定されました.
これらの変動の強度と相関の長さは,超伝導的移行温度 (T (c)) に向かって冷却すると増加した.
T (c) 以下の冷却は,電荷相関の相違の急激な逆転をもたらした.

結論:

観測された電荷変動は,初期電荷密度波 (CDW) の不安定性を示唆しています.
このCDWの不安定性は,研究されたコプラート材料の超伝導性と競合する.
発見は,コプラート超伝導体における競合する注文の直接的な証拠を提供します.

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