超高速のプレセッショナル・マグネチゼーションの逆転は,ピコ秒単位で磁場パルス形成をします
Th Gerrits1, H A M Van Den Berg, J Hohlfeld
1Research Institute for Materials, University of Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands.
Nature
|August 2, 2002
まとめ
研究者らは,より速い磁気メモリスイッチングのための新しい方法を開発しました. この技術は,磁気ランダムアクセスメモリ (MRAM) デバイスのデータエラーを防ぐために形状の磁気パルスを使用します.
科学分野:
- マテリアルサイエンス 材料科学
- 電気工学 電気工学とは
- 物理 物理学 物理学とは
背景:
- 磁気ランダムアクセスメモリ (MRAM) を含む磁気メモリデバイスは,1954年以来,速度,密度,および信頼性を向上させるために継続的に開発されています.
- コヘラント・ローテーションによる急速な磁化逆転は,ドメイン・ウォール・モーションが遅すぎるため,MRAMの性能にとって極めて重要です.
- MRAMの低臨界度で阻害された磁気システムは,鳴り響きに悩まされ,バックスイッチングとデータ整合性の問題を引き起こす可能性があります.
研究 の 目的:
- 低臨界減圧システムにおける磁性を逆転させるための新しい方法を提示する.
- 有害なリングを回避しながら,一貫した回転を介して信頼性の高い磁気化の逆転を達成するために.
- データ整合性を損なうことなく,MRAMデバイスのスイッチング時間を短縮するために.
主な方法:
- 磁気元素の固有の性質に合わせた特定の形状の磁場パルスを適用する.
- リトグラフィ的に構造されたマイクロメートルの大きさの円形パーマライエレメントを使用します.
- 3つの磁気化コンポーネントをすべて探査し,逆転ダイナミクスを確認します.
主要な成果:
- 低臨界減圧システムで信頼性の高いプレセッショナル磁気化逆転が実証されています.
- 約200ピコ秒 (ps) のスイッチングタイムを達成しました.
- 獲得した逆転速度は,自然減圧時間常数より10倍速い.
結論:
- 開発された方法は,一貫した回転を通じて磁気化を効果的に逆転させ,臨界以下で減圧されたシステムでのリングを回避します.
- 迅速かつ信頼性の高いスイッチングは,正確な形状の磁場パルスを使用してMRAM要素で達成できます.
- この進歩は,将来の磁気メモリ技術の潜在的な速度とデータ完全性を大幅に高めます.
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