カップレート超伝導体における超伝導ドームの向こうの鉄磁気順序
Tarapada Sarkar1, D S Wei2,3, J Zhang4
1Maryland Quantum Materials Center and Department of Physics, University of Maryland, College Park, MD 20742, USA.
Science (New York, N.Y.)
|May 2, 2020
まとめ
過剰にドーピングされたコプラートは 以前は従来の金属と考えられていましたが 4ケルビン未満の驚くべき移動性鉄磁気性を表しています La2- Ce CuO4 (LCCO) のこの発見は,強い電子相関がこれらの材料に影響することを示唆しています.
科学分野:
- 凝縮物質物理学
- 材料科学
- 量子材料について
背景:
- 従来の理解では,クプレート超伝導性は,ドーピングされた反鉄磁気分離器から発生します.
- 超伝導ドームを超えて,過剰にドーピングされたコプラートは通常,従来のフェルミ液体金属とみなされます.
研究 の 目的:
- 超伝導ドームを超えた 過剰ドーピングされたコプラートの 電子特性を調査する
- 電子相関がこれらの材料の行動に 作用するかどうかを判断する.
主な方法:
- 電子ドーピングされたLa2−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
- 低温 (4ケルビン以下) で磁気抵抗,磁気化,および極性ケル効果の測定.
主要な成果:
- 4ケルビン以下で,非常に過剰にドーピングされたLCCOの移動性鉄磁気順序の観測.
- 証拠には,負の,アニゾトロプ的,およびヒステリック磁気抵抗,ヒステリック磁気化,および極性ケール効果が含まれています.
- これらのシグネチャーは,金属の移動性鉄磁気性の特徴です.
結論:
- フェロマグネティズムの出現は,過剰にドーピングされたクプラートが単純なフェルミ液体であるという従来の見解に異議を唱える.
- この発見は,強力な電子相関が,超伝導段階を超えて,過剰にドーピングされたクプラートに著しく影響することを示しています.
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