マグネティック・ウェイル半金属Co2-xCrxMnGeにおける調整可能な異常なホールとネルスト効果
Mainak Dey Sarkar1, Anumita Bose2,3, Arka Bandyopadhyay4
1Department of Physics, University of Calcutta, 92 A P C Road, Kolkata 700009, India.
まとめ
この研究では,コアベースのヒュースラー合金を探索し,トポロジカル特性を持つ新しい磁性ウェイル半金属 (WSM) を特定しています. 異常なハール伝導性のような 異常な輸送行動を 劇的に増幅し スピントロニクスに希望を示しています
科学分野:
- 凝縮物質物理学
- 材料科学
- 固体物理学
背景:
- 磁性ウェイル半金属 (WSM) は,独特のトポロジカルな性質と異常な輸送を示す.
- 同基のヒュースラー化合物は,磁気とトポロジーの相互作用を探求するのに有望である.
- これらの材料を理解することは 先進的な技術的なアプリケーションの鍵です
研究 の 目的:
- トポロジカル・トランスポート特性を向上させるため,CO2-xCrxMnGe ハウスラー合金について調査する.
- 新しい磁気ウェイル半金属候補を特定するために.
- 材料の特性に対するCrドーピングの影響を調査する.
主な方法:
- 最初の原理の計算は,CO2-xCrxMnGe合金 (0 <= x <= 1) で行われた.
- この研究ではバンド構造,ウェイル点,フェルミ弧,ベリー曲線を分析した.
- 異常なホール伝導性と異常なネルスト伝導性が体系的に調査された.
主要な成果:
- Co2MnGeで固有のウェイル点が観察され,フェルミ弧と表面状態によって確認された.
- Crドーピングはベリー曲線と異常なホール伝導性 (AHC) を強化することが判明した.
- 様々なCr濃度で比較可能なAHC値を達成した (x=0, 0. 25, 0. 5).
結論:
- Crで代用ドーピングは,コアベースのヒュースラー合金におけるトポロジカルな性質と異常な輸送を効果的に強化する.
- これらの発見は,高性能の磁性WSMの開発の可能性を強調しています.
- この研究は,より優れたスピントロニックと電子機器への道を開きます.
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