大きなスピンホールの角度とコリネアルのスピンホールの伝導性を持つ二次元キラルペロフスキート
Ibrahim Abdelwahab1,2, Dushyant Kumar3,4, Tieyuan Bian5
1Department of Chemistry, National University of Singapore, Singapore 117543, Singapore.
Science (New York, N.Y.)
|July 18, 2024
まとめ
チラルのペロブスキットは,スピントロニクスの重要な特性である効率的な電荷-スピン変換を示す. この研究はこの変換を定量化し,高度なスピン光電子装置の可能性を明らかにしています.
科学分野:
- スピントロニクス
- 材料科学
- 有機-無機化学
背景:
- 二次元ハイブリッドの有機-無機ペロブスキットは,スピン光電子材料として有望である.
- これらの材料はキラル・スピン・テクスチャを持っています
- これらの材料の電荷-スピン変換効率は,ほとんど定量化されていません.
研究 の 目的:
- エナチオピュアなキラル・ペロフスキットにおける電気駆動の電荷-スピン変換を実証し,定量化する.
- これらの材料のスピンホール角度とスピン寿命を調査する.
- キラル・ペロフスキットで発生するスピン電流の性質を調査する.
主な方法:
- スキャン光電圧顕微鏡を用いた.
- 式 (R/S-MB) 2(MA) 3Pb4I13 (n=4) のエナティオプアキラルペロブスキートが調査されている.
- ラセミク対抗剤と低濃度の同類剤との比較結果
主要な成果:
- 高効率のチャージ・トゥ・スピン変換を達成した.
- 5%のスピンホール角度 (θsh) と,室温で75ピコ秒のスピン寿命を測定した.
- 従来のスピンとコリネアルのホールの伝導性は,横のスピン電流と平面外スピン電流によって示される.
結論:
- エナチオピュアなキラルペロフスキットは,有意な電荷-スピン変換効率を示している.
- これらの材料は,ラセミックおよび下位の同類物質を上回ります.
- 複数のスピン伝導性の存在は,その複雑なスピンダイナミクスとスピントロニックの応用の可能性を強調する.
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