CeRhIn5におけるフィールド調節量子批判性における電子内平面対称性破裂
F Ronning1, T Helm2, K R Shirer2
1Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Nature
|August 8, 2017
まとめ
研究者らは重フェルミオン超伝導体CeRhIn5で 変動するネマティック性を発見した. この電子ネマティック・フェーズは 量子的臨界点の近くに見られ,相関物質でネマティック性が一般的であることを示唆している.
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:
- 電子対称性が低下した状態である電子ネマティック性は,様々な超伝導体で観察される.
- 高温超伝導性におけるネマティック性の役割は,現在進行中の研究問題である.
- 重フェルミオン超伝導体は 複雑な電子現象を研究するための ユニークなプラットフォームを提供します
研究 の 目的:
- 重フェルミオン超伝導体CeRhIn5における電子ネマティック性の存在と性質を調査する.
- 関連電子系におけるネマティック性,量子批判性,超伝導性の関係を探求する.
主な方法:
- CeRhIn5における磁場誘発状態の実験観察
- 磁場下での平面内抵抗性アニソトロピーの測定
- マグネトストリクションと磁気トルクを分析し,対称性破裂と磁気移行を検出する.
主要な成果:
- 外平面の臨界場 (H* ≈ 28テスラ) の上のCeRhIn5における変動するネマティック相の証拠.
- この相は,格子対称性から独立して,有意な平面内抵抗性アニソトロピーを示している.
- メタマグネティズムと最小の格子歪みは ネマティック性の純粋な電子的起源を示唆します.
結論:
- この研究は,原型の重フェルミオン超伝導体における変動するネマティックな振る舞いを明らかにした.
- この発見は,ネマティック性と非従来の超伝導性の相互関係を強調しています.
- ネマティック性は,より広い範囲の相関材料に共通する特徴である.
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