オキシードで薄められた磁性半導体における高Tcフェロ磁性の室温崩壊と光の再活性化
Dengyu Pan1, Jianguo Wan, Guoliang Xu
1National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China. dypan@nju.edu.cn
Journal of the American Chemical Society
|September 28, 2006
まとめ
紫外線レーザー照射は,コバルト・ドーピングされた二酸化チタン (Co-doped TiO2) フィルムにおける鉄磁的秩序を活性化し,強化する. この光操作方法は,ナノ電子アプリケーションのための薄められた磁性半導体の磁性特性を調節する可能性を秘めています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- ナノテクノロジー ナノテクノロジー
背景:
- 稀薄磁性半導体 (DMS) は,スピントロニックアプリケーションに有望である.
- DMS素材の鉄磁気順序を制御することは,デバイスの機能性にとって極めて重要です.
- コドーピングされたTiO2は,時間が経つにつれて劣化できる鉄磁性特性を示します.
研究 の 目的:
- コドーピングされたTiO2.2の鉄磁気順にUVレーザー照射の影響を調査する.
- オキシードDMSの磁気特性を調節するための光誘発方法を探求する.
- 将来のナノ電子機器におけるこの方法の可能性を評価する.
主な方法:
- コドーピングされたTiO2ナノクリスタルフィルムの製造.
- フィルムをUVレーザー照射に晒す.
- 照射前後の磁気特性 (鉄磁気順序,強制力) の特徴.
- 光誘導効果の分析. 光誘導効果の分析. 光誘導効果の分析. 光誘導効果の分析.
主要な成果:
- 老化したコドーピングされたTiO2フィルムの鉄磁性秩序は衰退するが,UV照射によって回復し強化される.
- 紫外線照射は,照射時間の増加とともに強制力の減少につながります.
- 光誘導の捕まった電子は,鉄磁性を回復するメカニズムとして提案されています.
結論:
- UVレーザー照射は,コドーピングされたTiO2.2の鉄磁気秩序を操作するための有効な方法を提供します.
- 磁気特性の光誘発制御は,酸化DMS.の汎用的なアプローチです.
- この技術は,統合された磁気光学ナノエレクトロニクスの開発に有望である.
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