アンチフェロ磁性半導体 BaFMn0.5Te 独特の Mn 配列と赤色光発光
Haijie Chen1,2, Rebecca McClain1, Jiangang He3
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|October 8, 2019
まとめ
私たちは新しい半導体 BaFMn0.5Teを合成し 抗鉄磁性 (AFM) と赤色光発光 (PL) の両方を示しました この材料は,独特の磁気および光学特性により,光スピントロニクスアプリケーションに希望を示しています.
科学分野:
- 材料科学
- 凝縮物質物理学
- 半導体物理学
背景:
- 磁気と光電子の性質を組み合わせた半導体は,光スピントロニクスの進歩に不可欠です.
- 次世代の電子機器には,特化した機能を持つ新しい材料の開発が不可欠です.
研究 の 目的:
- 新しい混合アニオン半導体,BaFMn0.5Teを合成し,特徴づけ,オプト・スピントロニックの応用が可能です.
- BaFMn0.5Teの磁性および光発光特性について調査する.
主な方法:
- "パノラミック合成"技術とシンクロトロン放射線を用いたBaFMn0.5Teの合成.
- (3+1) 次元の超空間群Cmme(α01/2) 0ssを用いた構造の精錬.
- 磁性特性 (反鉄磁性) と光電子特性 (光発光) の特徴化には,スペクトロスコーピーと第一原理の計算を用いる.
主要な成果:
- BaFMn0.5Teをバンドギャップ1.76 eV,作業機能5.08 eVで成功して合成した.
- 90K未満の反鉄磁気 (AFM) と ~700 nmを中心とした強い赤色光発光 (PL) を観測した.
- Mn2+の順序による相応に調節された構造を持つZrCuSiAsのような層構造を決定した.
- 最初の原理の計算は,Te 5pとMn 3d軌道と反鉄磁気相互作用から生じる間接的なバンドギャップを確認した.
結論:
- BaFMn0.5Teは新しい混合アニオン半導体で,反鉄磁性および強力な赤色光発光特性がある.
- この材料のユニークな構造と電子特性により,光スピントロニクスアプリケーションの有望な候補となります.
- 時間分解したPLデータは,物質内の複数の放射性状態とエネルギー転送メカニズムを示唆しています.
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