超伝導体に偽装する:高圧BaCoO3,断熱鉄磁石
Haozhe Wang1, Xianghan Xu2, Danrui Ni2
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States.
Journal of the American Chemical Society
|September 20, 2023
まとめ
高圧合成により,六角形HP-BaCoO3が得られました. 超導体のような磁気的振る舞いを示すにもかかわらず, 詳細な分析はそれが超導体ではなく, 鉄磁気断熱体であることを確認しています.
科学分野:
- 材料科学
- 固体物理学
- マグネティズム
背景:
- 六角性バリウムコバルト酸化物 (BaCoO3) は,新しい電子および磁性特性を有する材料です.
- 高圧相を調査すると,環境条件ではアクセスできないユニークな結晶構造と振る舞いを明らかにできます.
研究 の 目的:
- 高圧条件下で六角形HP-BaCoO3を合成し,特徴づけること.
- この新素材の磁気と電気的性質を 解明するために
- HP-BaCoO3が超伝導性または鉄磁性特性を有するかどうかを判断する.
主な方法:
- 高圧合成 6 GPa と 1200 °C で
- 磁気化と電気抵抗性の測定を含む環境圧の特徴付け.
- 結晶構造と磁気性質の分析
主要な成果:
- 2H結晶構造の六角形HP-BaCoO3の合成に成功しました.
- 超伝導特性を模倣した130K未満のダイアマグネティックな行動と"半レビテーション"現象を観測した.
- 磁気化測定では,2Kでの有意な保持率 (0.22~1) の磁気性特性を明らかにした.
- 電気抵抗は 材料が断熱剤であることを確認した
結論:
- 六角形HP-BaCoO3は,超伝導体ではなく,鉄磁気分離器です.
- 観測された二磁性行動と半浮動は,その基礎にある鉄磁性性質とは異なる.
- 高圧合成は新しい材料の特性を探求する有効な経路です
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