スピンフィルターバン・ダー・ワールスのヘテロ構造における巨大トンネル磁気抵抗
Tiancheng Song1, Xinghan Cai1, Matisse Wei-Yuan Tu2
1Department of Physics, University of Washington, Seattle, WA 98195, USA.
Science (New York, N.Y.)
|May 5, 2018
まとめ
研究者は,スピンフィルターとして原子薄のクロムトリヨイド (CrI3) を使用して,新しい磁気トンネル結合を開発しました. 超薄磁気データストレージへの道を開いたのです 超薄磁気データストレージへの道を開いたのです
科学分野:
- 材料科学
- 凝縮物質物理学
- ナノテクノロジー
背景:
- マグネティック・マルチレイヤデバイスはデータ保存とセンシングに不可欠です.
- 既存の技術は小型化と性能の限界に直面しています.
研究 の 目的:
- ヴァン・デル・ワールス (vdW) ヘテロ構造を用いた新しい磁気トンネル交差点 (MTJ) を調査する.
- スピンフィルタートンネルバリアとしての原子薄型クロムトリヨイド (CrI3) の可能性を調査する.
主な方法:
- CrI3バリアとグラフェンコンタクトを持つ複数のスピンフィルター磁気トンネル接続 (sf-MTJ) の製造.
- 異なるCRI3層の厚さでトンネリング磁気抵抗 (TMR) を測定する.
- マグネティック・サークル・ディクロイズム (MCD) を用いて磁気配列を検知する.
主要な成果:
- CrI3の厚さでトンネリング磁気抵抗を大幅に強化しました.
- 低温で4層のsf-MTJで19,000%の磁気抵抗を達成しました.
- 原子的に薄いCrI3で固有の層ごとに反鉄磁気順序を観測した.
結論:
- 原子的に薄いCRI3は,VDWヘテロ構造における非常に効果的なスピンフィルターバリアとして機能します.
- この研究により 原子スケールでの磁気情報保存が可能になりました
- CrI3は高度なスピントロニック装置の有望な材料として特定されています.
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