(Ca4Al2O6) (Fe2As2) と (Ca4Al2O6) (Fe2P2) の超伝導体間の固体溶液における超伝導性の消失
Parasharam M Shirage1, Kunihiro Kihou, Chul-Ho Lee
1National Institute of Advanced Industrial Science and Technology (AIST), Central-2, 1-1-1 Umezono, Tsukuba, Ibaraki-305 8568, Japan. paras.shirage@gmail.com
Journal of the American Chemical Society
|September 1, 2012
まとめ
鉄基超伝導体 (Ca4Al2O6) ((Fe2As2) と (Ca4Al2O6) ((Fe2P2) の合金化により,固体溶液における超伝導性が抑制されました. 抵抗性の異常は,この抑制の磁気または構造的起源を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- ペロブスキート型鉄基超伝導体の調査は,高温超伝導性を理解するために重要である.
- 鉄のプニクチドおよび関連する材料の化学組成と超伝導特性との相互作用は,重要な研究分野です.
研究 の 目的:
- ペロブスキート型鉄基超伝導体 (Ca4Al2O6) (((Fe2As2) と (Ca4Al2O6) ((Fe2P2)) の合金効果を検証する.
- 固体溶液 (Ca4Al2O6) ((Fe2 ((As1-xPx)) 2) の超伝導特性を決定し,その相図を他の鉄基超伝導体と比較する.
主な方法:
- ステキオメトリック化合物 (Ca4Al2O6) (((Fe2As2) と (Ca4Al2O6) ((Fe2P2)) の合成と特徴付けについて.
- 固体溶液 (Ca4Al2O6) (((Fe2 (((As1-xPx) 2) の電気抵抗の準備と測定は,幅広いP置換 (x = 0.50から0.95) を介して行われます.
主要な成果:
- ステキオメトリック化合物は,それぞれ28Kと17Kの臨界温度 (Tc) を示した.
- 固体溶液は,0.50から0.95の範囲のxに対する超伝導性は示されず,その結果,他の鉄基超伝導体と比較してユニークな相図が得られました.
- 非超伝導的な固体溶液では,50〜100Kの抵抗性異常が観察されました.
結論:
- (Ca4Al2O6) ((Fe2As2) と (Ca4Al2O6) ((Fe2P2) の合金化により,幅広い組成範囲で超伝導性が抑制されます.
- 観測された抵抗性異常は,超伝導性の抑制は,他の鉄基超伝導体ファミリーの親化合物と同様に,磁性および/または構造的順序によって引き起こされる可能性が高いことを示唆しています.
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