DCジョセフソン超電流からの強く相関する超流体順序パラメータ
W J Kwon1,2, G Del Pace2,3, R Panza1,2
1Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy.
Science (New York, N.Y.)
|July 8, 2020
まとめ
研究者はフェルミオン超流体における直流 (dc) ジョセフソン超流を観測した. これは,強く相関する原子系における超流体の性質を測定するための方法を示しています.
科学分野:
- 凝縮物質物理学
- 量子流体
- 原子物理学
背景:
- 直流 (DC) ジョセフソン効果は,超流動性の性質を調査するために重要な量子現象です.
- 強く相互作用するシステムにおける超流体秩序のパラメータを理解することは,凝縮物質物理学の重要な課題です.
研究 の 目的:
- 強烈に相互作用するフェルミオン超流体におけるDCジョセフソン超電流の観測と特徴づけ.
- 調節可能な原子系におけるジョセフソン輸送と超流体順序のパラメータの関係を調査する.
主な方法:
- 強く相互作用するフェルミオン超流体におけるトンネル結成の製造.
- DCジョセフソン超電流の測定と,交差点における電流相関係.
- 交差点パラメータの関数としてゼロ抵抗状態とその分解の分析.
主要な成果:
- 適用電圧のないフェルミオン超流体におけるDCジョセフソン超電流の観測.
- 強いトンネルバリアのシナリオ型電流相関係が確認され,ジョセフソンの予測と一致する.
- バーディン-クーパー-シュリーファーからボース-アインシュタインの凝縮クロスオーバーのペア凝縮分数の決定.
結論:
- コーヘラント・ジョセフソン輸送は,多様な原子系における超流体順序のパラメータに敏感な探査機を提供します.
- 観測された現象は,強い電子相関が存在する場合でも堅実である.
- この技術は量子流体とその基本的な性質を 研究するための新しい経路を提供します
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