スイッチ可能なキラルトランスポート 充電順のカゴメタル CsV3Sb5
Chunyu Guo1,2, Carsten Putzke3, Sofia Konyzheva4
1Laboratory of Quantum Materials (QMAT), Institute of Materials (IMX), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland. chunyu.guo@mpsd.mpg.de.
Nature
|October 12, 2022
まとめ
研究者らは,中心対称のカゴメタルCsV3Sb5で電子磁気キラルアニソトロピー (eMChA) を観測した. 磁場によって制御されるこのキラル輸送は 充電順序と時間逆転の対称性破裂に関連しています
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:
- カイラル輸送係数は,アキラル金属で禁止されている異常な反応です.
- これらの効果には通常,反転の中心と強いキラルカップリングが欠けている材料が必要です.
- これまでの観測は 強い原子鏡対称性破裂を持つ物質に限られていた.
研究 の 目的:
- カゴメタルCsV3Sb5におけるキラル輸送を調査する.
- 電子キラリティと 充電順序と タイム・リバース・シンメトリー・ブレイキングの関係を探るため
- 中心対称性のある材料でキラル輸送の磁場制御を実証する.
主な方法:
- 平面内磁場の下での第2ハーモニック生成測定
- 温度に依存した測定で,電荷の順序を測る.
- 平面外磁場成分がキラリティに及ぼす影響の分析.
主要な成果:
- 35K未満のCsV3Sb5における有意な電子磁気キラルアニソトロピー (eMChA) が,その充電秩序状態 (T_CDW ≈ 94 K) 内で観察された.
- 電子キラリティと 単方向の電荷順序と タイム・リバース・シンメトリー・ブレイクとの間には 直接の相関が確立された
- チラリティは外平面フィールドコンポーネントによって設定され,フィールドサインを変更することによって切り替えることができます.
結論:
- CsV3Sb5は,その中心対称性にもかかわらず,強いキラル輸送を示す.
- 観測されたキラル輸送は,電荷順位状態と対称性破裂と密接に関連しています.
- この材料は,磁場によるキラル輸送を 前例のない制御で提供し,キラル電子の道を開きます.
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