新しい構造型のFeベースの超伝導体:CaAFe4As4 (A = K,Rb,Cs) とSrAFe4As4 (A = Rb,Cs)
Akira Iyo1, Kenji Kawashima1,2, Tatsuya Kinjo1,3
1National Institute of Advanced Industrial Science and Technology (AIST) , 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
Journal of the American Chemical Society
|March 5, 2016
まとめ
研究者は新しいFeベースの超伝導体,CaAFe4As4とSraFe4As4を発見し,新しい層構造を特徴づけた. これらの化合物は,約31〜36Kで独特の結晶秩序と超伝導性を表しています.
科学分野:
- 材料科学
- 固体物理学
- 超伝導性
背景:
- Feベースの超伝導体は,層状な性質があるため,多様な結晶構造で知られている.
- 既存の研究には (Ba(1-x) K(x)) Fe2As2のような固体溶液が含まれていますが,新しい構造型が必要です.
研究 の 目的:
- 新しいFeベースの超伝導体の発見を報告する
- これらの新しい材料の結晶構造と超伝導性特性を特徴づける.
主な方法:
- CaAFe4As4およびSrAFe4As4化合物の合成と特徴付け
- 粉末のX線微分法で結晶構造と空間群を決定する.
- 超伝導性の移行温度を測定する.
主要な成果:
- 新しい構造型のFeベースの超伝導体:CaAFe4As4 (A = K,Rb,Cs) とSrAFe4As4 (A = Rb,Cs) の発見.
- これらの化合物は独特の層構造 (AeA1144) を表しており,Fe2As2層の間にAとAの層が交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互を交互に交互に交互に交互を交互に交互に交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互する.
- 超伝導的移行温度は約31〜36Kの範囲で観察されました.
結論:
- AeA1144はFeベースの超伝導体や他の材料における新しい構造モチーフを表しています.
- この新しい構造の鍵となるのは オーダーされたAとA層です
- これらの線形化合物は,超伝導体における構造-特性関係を研究するためのプラットフォームを提供します.
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