フェロマグネティズムの電場制御
1Laboratory for Electronic Intelligent Systems, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan. ohno@riec.tohoku.ac.jp
Nature
|January 5, 2001
まとめ
研究者らは,半導体合金における鉄磁性の電場制御を実証した. このブレークスルーにより,磁気特性の可逆調節が可能になり,磁気電子学とスピントロニクスの応用に新たな道が開きます.
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
- 固体化学 固体化学
背景:
- 磁気材料は情報技術にとって極めて重要ですが,その性質は通常,準備後に固定されます.
- 磁気材料の性質を外部から制御することは,磁気電子とスピントロニクスにおける進歩にとって非常に望ましい.
- 磁力の電気操作は,半導体における導電性制御とは異なり,重要な課題であり続けています.
研究 の 目的:
- 薄膜半導体合金における鉄磁性の電場制御を実証する.
- 電気刺激を用いて磁気特性を逆転的に変化させる可能性を調査する.
- スピントロニックデバイスにおける新しい機能の可能性を調査する.
主な方法:
- 半導体合金による隔離ゲートフィールド効果トランジスタ構造の製造.
- 薄膜半導体材料に電場を適用する.
- 異なる電場下で穴誘発の鉄磁性の移行温度を測定する.
主要な成果:
- 半導体合金におけるフェロマグネティズムに対する電場制御の成功実証.
- 穴誘発の鉄磁気力の移行温度における同熱および可逆的変化.
- 材料レベルでの磁性特性の電気的調節の証拠.
結論:
- 鉄磁性の電場制御は,薄膜半導体合金で達成可能である.
- この方法は,新しいスピントロニックおよび磁電電子装置の開発のための経路を提供します.
- 磁気特性を電気的に調節する能力は,重要な基本的および技術的な意味を持つ.
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