LiCu2P2における超伝導性の欠如
1National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China.
Journal of the American Chemical Society
|January 27, 2011
まとめ
この研究では,LiCu(2) P(2) の超伝導性を調査しました. 繰り返しの合成と測定では,2K以上の超伝導的移行は見つかりませんでしたが,金属の振る舞いとキュリー・ワイス磁性を示しています.
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
- 固体化学 固体化学
背景:
- 以前の報告では,LiCu2P2が3.7Kの臨界温度 (Tc) を有する超伝導性を示すことが示唆されていた.
- 銅基プニクチドは,新しい電子特性に対する関心分野である.
研究 の 目的:
- LiCu(2) P(2) で報告された超伝導性を独立して検証する.
- 合成されたLiCu(2) P(2) サンプルの電子および磁気特性を特徴付ける.
- LiCu(2)P(2) の特性に対するステキオメトリーの影響を調査する.
主な方法:
- 多結晶および単結晶のLiCuの合成 (((2) P (((2)).
- 2Kから300Kまでの温度依存レジスティビティとDC磁化測定.
- ホール効果と磁気抵抗 (MR) の測定.
- Li(1-x) Cu(2) P(2),LiCu(2-x) P(2),およびLi(1+x) Cu(2-x) P(2) の様々なステキオメトリの合成について
主要な成果:
- 2K以上のレジスティビティまたはDC磁化では,合成されたサンプルで超伝導的移行は観察されなかった.
- レジスティビティ測定は金属の振る舞いを示した.
- DC磁気化は,2Kから300Kまでのキュリー=ワイスの振る舞いを示した.
- ホール効果とMR測定は,LiCu(2) P(2) の単帯域特性を示唆しました.
結論:
- 以前報告されたLiCu(2) P(2) の超伝導性は再現できませんでした.
- 合成されたLiCu(2) P(2) は,局所的なモメントと一致する金属特性と磁気行動を示す.
- ステキオメトリーの変動は,調査されたLiCu(2) P(2) システムで超伝導性を誘導しませんでした.
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