狭いグラフェンナノリボンのジグザグの縁の部屋温度の磁気順序
Gábor Zsolt Magda1, Xiaozhan Jin2, Imre Hagymási3
1Research Centre for Natural Sciences, Institute of Technical Physics and Materials Science, Nanotechnology Department, 2D Nanoelectronics "Lendület" Research Group, Budapest 1121, Hungary.
Nature
|October 31, 2014
まとめ
特定のジグザグ的な方向性を持つエンジニアリングされたグラフェンのエッジは,室温の強力な磁力を発揮します. グラフェンナノリボンにおけるこの制御された磁気順序は,高温スピントロニックデバイスの可能性を開きます.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 炭素のような非磁性物質は,新しいs-p電子磁性のために探求されています.
- グラフェンの原子欠陥はペア化されていないスピンを宿すことができますが,長距離磁気秩序はよく理解されていません.
研究 の 目的:
- 堅固な磁気秩序のためのグラフェンエッジの原子規模の工学を調査する.
- グラフェンの欠陥結合磁気モメントから発生する磁性の条件を調査する.
主な方法:
- グラフェンナノリボンナノ製造のためのスキャニングトンネル顕微鏡を用いた.
- 精密に定義されたナノリボンで,制御された結晶学的なエッジ・オリエンテーション (ジグザグ対アームチェア) がある.
主要な成果:
- ジグザグ状のグラフェンナノリボン (<7 nm) は,電子バンドギャップ (0.2-0.3 eV) を示し,スピンの順序を示している.
- 半導体から金属への移行は,リボン幅の増大とともに観察され,磁気結合の切り替え (アンチフェロマグネティックからフェロマグネティックへ) を意味する.
- ジグザグ状のグラフェンエッジの磁気秩序は,室温まで安定性を示した.
結論:
- グラフェンのエッジの原子スケールエンジニアリング,特にジグザグ方向化は,強力な磁気秩序を誘導することができます.
- 制御された磁石グラフェン構造は,環境条件下で動作するスピントロニックデバイスの可能性を示しています.
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