粒状の記録媒体における磁気スイッチングの究極の速度

I Tudosa¹, C Stamm, A B Kashuba

¹Stanford Synchrotron Radiation Laboratory, PO Box 20450, Stanford, California 94309, USA.

Nature

|April 23, 2004

まとめ

研究者は,非常に短い,高強度の磁場パルスが,決定的磁気記録を混乱させることを発見しました. この現象は,鉄磁気秩序の一時的な喪失によって引き起こされ,磁気データ保存の速度に根本的な限界を設定します.

科学分野:

物理物理学物理学とは
マテリアルサイエンス材料科学
電気工学電気工学とは

背景:

磁気メモリデバイスは,磁気化を制御することによってデータを保存します.
プレセッショナル・スイッチングは,磁気記録の最も速い方法である.
より速い録音には,短めのスイッチングタイムが必要であり,これは,書き込みパルス振幅を増やすことによって達成されます.

研究の目的:

極端な磁場パルスのプレセッショナルスイッチングへの影響を調査する.
書き込みパルス振幅を増加させることで,スイッチング時間が無期限に短縮されるかどうかを判断する.
決定的な磁気記録速度の究極の限界を特定するために.

主な方法:

非常に高い磁場の非常に短いパルスを磁気媒体に適用する.
極端な条件下での磁気化のスイッチング行動の観察と分析.

主要な成果:

プレセッショナル・スイッチングは,極端なパルス条件下では非決定的になります.
スイッチングは,幅広い磁場でランダムに発生します.
フェロ磁気秩序の一時的な崩壊が観察される.

結論:

決定性磁気記録には究極の速度制限があります.
極端な磁場パルスは,プレセッショナル・スイッチングの予測可能な性質を乱します.
この限界を理解することは,磁気メモリ技術の進歩に不可欠です.

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