サブテラヘルツで生成された反鉄磁気マグノンのスピン電流
Junxue Li1, C Blake Wilson2,3, Ran Cheng1,4
1Department of Physics and Astronomy, University of California, Riverside, CA, USA.
Nature
|January 29, 2020
まとめ
研究者は,反鉄磁性ヘテロ構造でサブテラヘルツのスピンポンプを実証した. この研究は,反鉄磁気共鳴からの純粋なスピン電流の生成と電気検出を示し,超高速スピントロニックデバイスへの道を切り開いています.
科学分野:
- 凝縮物質物理学
- スピントロニクス
- 材料科学
背景:
- 反鉄磁石は超高速装置の鉄磁石よりも速いスピンダイナミクスを提供します.
- 反鉄磁石でスピン電流を生成し,電気的に検出することは依然として課題です.
研究 の 目的:
- サブテラヘルツのスピンポンプと,反鉄磁気ヘテロ構造における純粋なスピン電流の電気検出を実証する.
- 高周波の反鉄磁石におけるマグノン刺激とスピン電荷変換を調査する.
主な方法:
- 単軸反鉄磁性Cr2O3と重金属 (Pt,β-Ta) を使用したヘテロ構造の製造.
- 0.240THzと2.7Tの反鉄磁共振 (AFMR) の刺激と10.5Tの第2共振
- 逆スピンホール効果による生成されたスピン電流の電気検出.
主要な成果:
- Cr2O3/重金属ヘテロ構造のAFMRと第2共振の両方から純粋なスピン電流の生成と検出に成功した.
- 探知器の金属 (Pt/Ta) または磁場方向の切り替え時に電圧の極性反転によって純粋なスピン電流の明確な確認.
- 温度依存とスピンシーベック効果の測定は,スピン電流への一貫したおよび非一貫したマグノン貢献を示しています.
結論:
- この研究は,反鉄磁石における純スピン電流のサブテラヘルツスピンポンプと電気検出を明示しています.
- 発見は,高周波でのスピン-電荷変換におけるユニークなマグノン刺激特性を強調しています.
- この結果は,反鉄磁性材料に基づく超高速スピントロニック装置の開発に新しい道を開きます.
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