ホールドーピングSmNiO2で40K近くの大量超伝導
S Lin Er Chow1, Zhaoyang Luo2, A Ariando3
1Department of Physics, Faculty of Science, National University of Singapore, Singapore, Singapore. le.chow@u.nus.edu.
Nature
|March 20, 2025
まとめ
研究者らは酸化ニッケルフィルムに 40Kに近い高温超伝導性を発見した. この (Sm-Eu-Ca-Sr) NiO2の突破は,従来のコペラートを超えたクーパーペアリングの探索のための新しい可能性を提供します.
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- キュープレート (Ba-La-Cu-O) の超伝導性は30K近くで発見され,より高い臨界温度 (Tc) の層状酸化物超伝導体の研究を促した.
- 最近のニケラート超伝導性発見にもかかわらず,銅のない同構造システムで30K以上のクーパーペアリングを達成することは困難でした.
研究 の 目的:
- 新しいニケラート系における超伝導性を報告する
- 高温超伝導性における銅以外のd電子金属酸化物の可能性を調査する.
主な方法:
- d9-xホールドーピング,遅い希土,無限層のニッケル酸化物 (Sm-Eu-Ca-Sr) NiO2薄膜の合成
- ゼロレジスタンス状態の測定とマイスナー効果による超伝導性の特徴化.
- レジスティビリティと残留レジスティビリティ比率を含む材料の性質の分析
主要な成果:
- 超伝導性は,周囲の圧力下で40Kに近づく臨界温度 (Tc) で観測される.
- 31Kでゼロレジスタンス状態が確認されました ミッセンナー効果の証拠と共に
- 合成されたフィルムは超低抵抗性 (~0.01 mΩ·cm) と最小の構造的欠陥を示した.
結論:
- 銅のないニッケル酸化物システムで高温超伝導性を証明した.
- 高Tcクーパーペアリングのプラットフォームとして,強く相関するd電子金属酸化物の可能性を強調した.
- 超伝導性を探求し理解するための 新しい道を開きました
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