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電子ドーピングされたNd1.85Ce0.15CuO4で競合する基底状態としての反鉄磁気順序
H J Kang1, Pengcheng Dai, J W Lynn
1Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996-1200, USA.
Nature
|May 30, 2003
まとめ
銅酸化物における高過渡温度超伝導性は,反鉄磁力学と競合する. この研究は,ドーピングタイプに関係なく,これらの材料における普遍的な競合する基底状態としての反鉄磁性秩序を明らかにします.
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:
- 超伝導性は,高過渡温度 (高T ((c)) の銅酸化物において複雑な現象である.
- 競合する基底状態を理解することは,高T (c) 超伝導性を説明する上で極めて重要です.
- 反鉄磁気は,理論的には競合する基底状態であると予測されています.
研究 の 目的:
- 高T (c) 銅酸化物における超伝導性と競合する基底状態の性質を決定する.
- この競合する基底状態が,異なるドーピングタイプ (電子対穴) にわたって普遍的であるかどうかを確認する.
- 超伝導状態から反鉄磁気状態への量子相変化を調査する.
主な方法:
- 電子ドーピングされたNd1.85Ce0.15CuO4.4の輸送測定
- 電子ドーピングされたNd1.85Ce0.15CuO4.4のニュートロン散乱実験
- 磁場を適用して,上部臨界場に到達する (B) (c2)).
主要な成果:
- 静的,相応の,長距離の秩序付けられた反鉄磁気状態が,電子ドーピングされた材料で観察されました.
- 誘導された磁気モメントは,B (c2) で飽和するまで,適用されたフィールドに沿って線形にスケールされます.
- この発見は,ホールドーピングされた材料に関する以前の研究と組み合わせて,抗鉄磁性を競合する基底状態として確認しています.
結論:
- 抗鉄磁性秩序は,高T (c) 銅酸化物における普遍的な競合する基底状態である.
- この普遍性は,ドーピングが電子ベースか穴ベースかに関係なく当てはまります.
- この研究は,高T (c) 超伝導性を支配する基本的な物理学の重要な洞察を提供します.
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