可視光とテラヘルツパルス光による ε-鉄酸化物磁性ナノ粒子の急速なファラデー回転
Shin-Ichi Ohkoshi1, Kenta Imoto1, Asuka Namai1
1Department of Chemistry, School of Science , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-0033 , Japan.
Journal of the American Chemical Society
|January 16, 2019
まとめ
化学合成された磁性ナノマテリアルは 光に反応する磁性を表しています 可視光は磁気化の逆転を誘発し,テラヘルツ (THz) 光は高度な磁気装置での潜在的な使用のために超高速の磁気光学効果を誘発する.
科学分野:
- スピン化学
- 光学材料科学
- ナノ磁力学
背景:
- 光または電磁波に反応する磁気は,スピン化学と光学材料科学の重要な分野である.
- 外部刺激で制御可能な磁気特性を有する材料の開発は 次世代の技術にとって極めて重要です
研究 の 目的:
- ε-鉄酸化物ベースの磁性ナノマテリアルの光誘発磁化逆転と超高速磁光効果を調査する.
- 高密度磁気メモリと高速磁気装置におけるこれらの材料の潜在的な応用を探求する.
主な方法:
- ガリウム-チタン-コバルト代替 ε-Fe2O3 (GTC-ε-Fe2O3) フィルムと ε-Fe2O3 ナノ粒子の化学合成
- 可視光パルスレーザーとテラヘルツ (THz) パルスレーザーによる照射.
- ランダウ-リフシッツ-ギルバート計算を用いた理論的実証.
主要な成果:
- 可視光パルスレーザー照射によるGTC-ε-Fe2O3フィルムの磁化逆転,ファラデー効果のシグナルを切り替える.
- ε-Fe2O3フィルムに対するパルスTHz光照射は,400fs以内の超高速のファラデー回転をもたらした.
- ストキャスティック・ランдау・リフシッツ・ギルベルト計算により,観測された超高速磁気光学ダイナミクスを検証した.
結論:
- ε-鉄酸化物の磁性ナノマテリアルは,光に反応する磁性特性を有しています.
- これらの材料は,高密度磁気メモリメディアと高速磁気回路装置のアプリケーションに希望を示しています.
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