純粋な鉄磁気コンドの格子における奇妙な金属の振る舞い
Bin Shen1, Yongjun Zhang1, Yashar Komijani2
1Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, China.
Nature
|March 6, 2020
まとめ
奇妙な金属は,通常,反鉄磁性に関連して,鉄磁石に現れる可能性があります. この研究は 絡み合いが誘発する 鉄磁気量子批判性を明らかにし 奇妙な金属の振る舞いに関する 過去の仮定に挑戦しています
科学分野:
- 凝縮物質物理学
- 量子材料科学
背景:
- 量子クリティカルポイント (QCP) の近くの奇妙な金属の性質は謎のままです.
- 奇妙な金属は通常,非常識な超伝導性と反鉄磁性QCPと関連しており,高度に絡み合った量子状態を示唆しています.
- フェロマグネットは以前は 弱い絡み合いのせいで 奇妙な金属の宿主と考えられていました
研究 の 目的:
- 圧力を誘発したQCPで 鉄磁気材料の奇妙な金属の振る舞いを調査する.
- 磁気量子批判性における量子絡み合いの役割を調査する.
- 奇妙な金属は 抗鉄磁性QCPと 限定的に結びついているという 支配的な概念に挑戦する
主な方法:
- 特定の熱と圧力下での抵抗性測定を用いた.
- 圧力誘発QCPの近くにある 鉄磁気コンドー格子物質を調査した
- ローカルモメントと伝導電子の絡み合いのパターンの変換を分析した.
主要な成果:
- 鉄磁気変遷は連続してゼロ温度まで抑制され,金属の奇妙な振る舞いを誘導することが示された.
- 強力な磁性アニソトロピーが重要な要因として特定され,三重共振バレンスの結合を通じて絡み合いを導入した.
- QCPでトリプレート共振バレンスのペアからコンドー・エンテラブル・シングレットペアに,フェルミ表面体積ジャンプを引き起こした単一の変換を観測した.
結論:
- 磁性量子批判性は 量子絡みによって引き起こされる 奇妙な金属の振る舞いを宿している
- 強い磁性アニソトロピーは,フェロマグネットの絡み合いを生み出す上で重要な役割を果たします.
- 反鉄磁性の破壊ではなく 量子絡み合いが 奇妙な金属現象の 共通の原動力として提案されています
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