イコサヘドラル準結晶における長距離磁気秩序の実験観測
Ryuji Tamura1, Asuka Ishikawa2, Shintaro Suzuki1
1Department of Materials Science and Technology, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.
Journal of the American Chemical Society
|November 17, 2021
まとめ
研究者は,金,ガリウム,ガドリウムまたはテリビウムで作られたイコサヘドラル準結晶 (i QC) で長距離磁気秩序を発見した. この発見は,磁気配列が欠けている準結晶に関する以前の仮定に異議を唱える.
科学分野:
- 材料科学
- 凝縮物質物理学
- マグネティズム
背景:
- 準結晶 (QC) は通常,長距離磁気秩序を欠いている.
- 磁性準結晶に関する以前の研究では スピンガラスのような行動が報告されました
研究 の 目的:
- 本物のイコサヘドラル準結晶の 遠距離磁気秩序の可能性を調査する.
- 磁性準結晶化合物 Au-Ga-Gd と Au-Ga-Tb を合成し,特徴づけること.
主な方法:
- Au-Ga-GdとAu-Ga-Tbのイコサヘドラル準結晶の合成
- 磁気感受性と特異的な熱の測定
- ニュートロン偏光実験
主要な成果:
- Au65Ga20Gd15 i QCは,磁気ブレッグピークで23Kのフェロ磁気移行を示しています.
- Au65Ga20Tb15 i QCは,ニュートロン difraktionによって確認された16 Kのフェロ磁気行動も示しています.
- これは実際の準結晶における 遠距離磁気秩序の 最初の観測です
結論:
- 本物のイコサヘドラル準結晶は,長距離の鉄磁気秩序を示すことができる.
- これらの発見は 準周期系における 奇特な磁気現象の研究に 新たな道を開きます
- この研究は,イコサヘドール対称性を持つ準結晶が,新しい磁気アプリケーションに持つ可能性を強調しています.
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