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EuRbFe4におけるスメティックペア密度波の順序として4
He Zhao1, Raymond Blackwell1, Morgan Thinel2,3
1Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA.
Nature
|June 28, 2023
まとめ
研究者は,EuRbFe4As4超伝導体で新しいゼロフィールドペア密度波 (PDW) 状態を発見しました. この状態は,他の有秩序な状態から独立してユニークな超伝導ギャップの調節を示し,従来の超伝導性に新しい洞察を提供します.
科学分野:
- 凝縮物質物理学
- 超伝導性の研究
- 材料科学
背景:
- ペア密度波 (PDW) は,超伝導状態で変換対称性を破るものである.
- これまでのPDWの証拠は,高磁場または他の命令と共存に限定されていました.
- ゼロフィールドのPDWは 他の州から独立して 捉え難いままです
研究 の 目的:
- 主要な,ゼロフィールドペア密度波 (PDW) 状態の存在を調査する.
- 鉄のプニクチド EuRbFe4As4 の超伝導性の性質を特徴づけること.
- PDW,磁気,および他の電子命令の間の関係を決定する.
主な方法:
- スペクトル画像スキャニングトンネル顕微鏡 (SI-STM) が使用された.
- SI-STMの発見を裏付けるために,大量測定が行われました.
- 温度と磁場の変化はPDW状態を検知するために使用されました.
主要な成果:
- EuRbFe4As4でゼロフィールドのPDW状態が確認された.
- 超伝導ギャップの長距離,一方的な調節が観察されました.
- PDW状態は磁気 (Tm ≈ 15 K) と超伝導性 (Tc ≈ 37 K) と共存する.
- PDW状態はTm以上で消滅し,転移と回転の対称性が回復する.
結論:
- EuRbFe4As4は,他の密度波の順序から独立した,原始的な,ゼロフィールドのPDW状態を宿している.
- この材料のPDW状態は,スメティックな順序を示しています.
- この発見により 非従来の超伝導状態の理解が進んでいます
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