タイム・リバース・シンメトリー・ブレイキング・スーパーコンダクタ
S Y Frank Zhao1, Xiaomeng Cui1, Pavel A Volkov1,2,3
1Department of Physics, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|December 7, 2023
まとめ
エンジニアは,曲がったコプレート超伝導体インターフェイスを使用して,新しいジョセフソンダイオードを作成しました. これらの装置は調節可能な特性を持ち,潜在的なトポロジカルアプリケーションのための時間逆行対称性の制御を可能にします.
科学分野:
- 凝縮物質物理学
- 材料科学
- 超伝導性
背景:
- カップレート結晶の歪んだヴァン・デル・ワールス (vdW) インターフェースは,超伝導性の特性を設計することを可能にします.
- ジョセフソン・ジャンクション (JJs) は,超伝導電子や量子装置にとって極めて重要です.
研究 の 目的:
- カップレート結晶における歪んだvdWジョセフソン結合 (JJs) を構築し,調査する.
- これらのエンジニアリングされたインターフェイスにおける超伝導順序パラメータと時間逆行対称性 (TRS) の制御を調査する.
主な方法:
- Bi2Sr2CaCu2O8+の間の原子的に鋭いインターフェイスを作成するために,冷凍組立技術を使用しました.
- 45°近くの回転角度を持つVdW JJを製造した.
- 断片的なシャピロのステップとフラウンホーファーのパターンを用いて,交差点の行動を分析した.
主要な成果:
- 高品質のVdW JJが 固有の限界に近づいています
- 観測された現象は,45°の回転に近い時間逆行対称性 (TRS) によって関連付けられた2つの変性基底状態と一致する.
- 磁場のないジョセフソンダイオードを実現するために,TRSの制御可能な破壊を証明した.
結論:
- ジョセフソンダイオードを 歪んだコプレートインターフェイスで設計した.
- 超伝導装置における時間逆行対称性を制御する方法を確立した.
- より高温のトポロジック装置の開発への道が開かれました.
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