オールインオールアウト磁気分離器の移動金属ドメイン壁
Eric Yue Ma1, Yong-Tao Cui2, Kentaro Ueda3
1Geballe Laboratory for Advanced Materials (GLAM), Stanford University, Stanford, CA, USA. Department of Applied Physics, Stanford University, Stanford, CA, USA.
Science (New York, N.Y.)
|October 31, 2015
まとめ
研究者らは,磁気絶縁体Nd2Ir2O7に高伝導性磁気領域の壁を発見した. これらのドメイン壁は,温度に依存しない耐性とユニークな性質を示し,磁気分離器に関する以前の理論に挑戦しています.
科学分野:
- 凝縮物質物理学
- 材料科学
- 固体物理学
背景:
- 磁気領域壁は,異なる順序を持つ磁気領域間のインターフェイスです.
- 磁気分離器では,磁気秩序が乱れたため,ドメイン壁が異なる電気的性質を持つことが期待されていた.
- 以前の理論では,磁気分離器内のドメイン壁の電気的振る舞いの有意な変化を仮定した.
研究 の 目的:
- 磁気隔離器 Nd2Ir2O7 の磁気領域壁の電気的性質を調査する.
- この特定の材料のドメイン壁が異常な伝導性を示すかどうかを実験的に決定する.
- 異なる温度と磁場下での 領域壁の振る舞いを特徴づける.
主な方法:
- 輸送測定は電気的特性を探査するために使用されました.
- 空間的に解明されたマイクロ波阻力顕微鏡を用いて,ナノスケールでの伝導性をマッピングした.
- Nd2Ir2O7で実験が行われ,この材料は完全に磁気である.
主要な成果:
- Nd2Ir2O7に高伝導性磁場壁が発見されました.
- これらのドメイン壁は,ほぼ温度に関係なく,正方形あたり約1キロのレジスタンスを持っています.
- ドメインの壁は滑らかな形状を示し,障害によるピンがなく,オールインオールアウトの磁気順に一致する反応を示した.
結論:
- Nd2Ir2O7の高伝導性ドメイン壁の発見は,既存の磁気分離器のモデルに挑戦しています.
- これらの発見は,ドメイン壁が導電経路である可能性を示唆しています.
- これらのドメイン壁のユニークな性質は 磁気材料における 奇妙な電子現象を 探求するための新しい道を開きます
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