連続的に調節可能なランダムなフィールド内のフェロマグネット
D M Silevitch1, D Bitko, J Brooke
1The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA.
Nature
|August 3, 2007
まとめ
不規則な磁石は,キュリー温度を超えた単一の磁気反応を示し,これはT(C) で異常な分岐をします. この発見は,ランダムフィールド問題の理解を前進させ,アプリケーションのドメインウォールピニングの洞察を提供します.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- マグネティズム (磁気) とは
背景:
- ほとんどの物理系は乱れているが,理論モデルでは乱れを軽微な乱れとして扱うことが多い.
- キュリー温度 (T ((C)) の近くのフェロマグネットは,ランダムな化学置換で通常抑制された重要な振る舞いを示します.
- 乱れたフェロマグネットにおける大量測定は,通常,重大な乱れレベルを下回る質的に新しい現象を明らかにしません.
研究 の 目的:
- モデルの乱れた磁石の磁気反応を調査する.
- 乱れた磁気系における新しい現象を特定する.
- 基礎物理学と技術応用への影響を調査する.
主な方法:
- 乱れた磁気システムのモデルを研究する.
- 磁気反応,特に感受性を測定する.
- 外部磁場を磁化方向に横切って適用する.
主要な成果:
- キュリー温度 (T (C)) 以上で単一の磁気反応が観察されました.
- この特異性は,T ((C)) の正確さで異常な分岐を示した.
- 応答は,横断外磁場によって誘発されたランダムな内部フィールドから発生します.
結論:
- 乱れた磁石は,キュリー温度の近くでユニークな行動を示します.
- 観測された現象は,磁気システムのランダムフィールド効果と関連しています.
- 発見は,磁気アプリケーションに不可欠なドメインの壁ピニングのチューニングの可能性を示唆しています.
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