シングルスピン顕微鏡でナノスケールで2D材料の磁性を探査する
L Thiel1, Z Wang2,3, M A Tschudin1
1Department of Physics, University of Basel, Klingelbergstrasse 82, Basel CH-4056, Switzerland.
Science (New York, N.Y.)
|April 27, 2019
まとめ
研究者はスキャニングシングルスピン磁気測定を用いてクロミウム (CrI3) 2D vdW結晶を研究した. 磁気化は層数に依存し,構造の変化は磁気順序を変化させることができます.
科学分野:
- 凝縮物質物理学
- 材料科学
- ナノテクノロジー
背景:
- 二次元の (2D) ヴァン・デル・ワールス (vdW) 結晶は鉄磁性を示し,重要な研究に関心を持っています.
- 磁石のナノスケールの磁気特性を理解することは,この分野を前進させる上で極めて重要です.
研究 の 目的:
- クロミウム (CrI3) vdW結晶のナノスケール磁気特性を定量的に調査する.
- 原子的に薄いCRI3で磁気化,欠陥,磁気領域をイメージする.
主な方法:
- ダイヤの窒素空隙 (NV) センターを持つスキャニング単回転磁気測定法を使用した.
- CrI3の原子的に薄いvdW結晶に適用された技術.
主要な成果:
- モノレイヤのCrI3磁化量は,平方ナノメートルあたり約16ボア磁子であることが決定された.
- 奇数層のサンプルの磁化が観察され,偶数層のサンプルの磁化が消失した.
- 構造変更により,フェロ磁気状態と反フェロ磁気状態の間の磁気順序を切り替えることが示された.
結論:
- シングル・スピン・スキャニング・マグネトメトリは,2D vdW マグネチズムを研究するための有益な技術である.
- CrI3における層依存磁化と切り替え可能な磁性オーダリングは,スピントロニックアプリケーションのための新しい道を提供します.
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