磁気トンネル交差点における電動力と巨大な磁気抵抗
Nam Hai Pham1, Shinobu Ohya, Masaaki Tanaka
1Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Nature
|March 10, 2009
まとめ
新しい電気運動力 (e.m.f.) 静的な磁場を持つ鉄磁気回路における電子のスピンから生じる. このスピンベースのEMFは, そして巨大な磁気抵抗は,新しい磁気センサーとスピン電池を可能にします.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- スピントロニクス (Spintronics) は,スピントロニクス (Spintronics) を開発したものです.
- 量子力学は,量子力学という
背景:
- 従来の電気運動力 (e.m.f.) ファラデーの法則によると,時間変動の磁場から発生します.
- スピンベースのEMFです. 静的な磁場におけるフェロ磁性物質の予測は,時間変動磁化に関連しています.
- この回転は E.M.F. 磁気エネルギーを電気エネルギーに変換する.
研究 の 目的:
- スピンベースのe.m.f.の誘導を実証する. 静的な磁場を持つ磁気トンネルの交差点にある.
- 磁気量子トンネリングとスピン力が関与する根本的なメカニズムを調査する.
- 観察された現象の潜在的応用を探求する.
主な方法:
- マグネティック・トンネル・ジャンクションを亜鉛混合構造のMnAs量子ナノマグネットで利用する.
- 静的な磁場を適用して,EMFを誘導する.
- E.M.F.を測定する そして,時間の経過とともに磁気抵抗.
主要な成果:
- スピンベースのe.m.f.を成功裏に誘導した. 静的な磁場の中で.
- 観測されたe.m.f. 10^210^3秒のタイムスケールで動作する.
- 特定のバイアス電圧に対して最大100,000%の巨大な磁気抵抗を測定した.
- e.m.f.を代入した. 超パラ磁性ナノ磁石の量子トンネリングによる磁気エネルギーの変換に.
結論:
- ファラデーの法則は,磁性ナノ構造のスピン起源力を含めるために一般化する必要があります.
- この発見は,スピンベースのe.m.f.の存在を裏付けている. 静的な磁場の中で.
- 潜在的な用途には,高感度磁気センサーや"スピンバッテリー"のような新しいアクティブデバイスが含まれます.
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