トポロジカル・セミメタル・モリブデン・フォスフィードにおける三成分フェルミオンの観測
B Q Lv1,2, Z-L Feng1,2, Q-N Xu1,2
1Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Nature
|June 20, 2017
まとめ
研究者はモリブデン・フォスフィードに新しい3つの成分フェルミオンを発見し,標準のディラク,ウェイル,マジョラーナ分類を超えた. この発見は,凝縮された物質のシステムにおける非伝統的なフェルミオン物理学の探索のための新しい道を開きます.
科学分野:
- 凝縮物質物理学
- 量子力学について
- 材料科学
背景:
- 量子場論におけるフェルミオンはディラック,ウェイル,マジョラーナに分類される.
- ディラック・フェルミオンとウェイル・フェルミオンは凝縮物質で確認されているが,マジョラーナフェルミオンの存在は実験によって支持されている.
- 結晶の対称性はロレンツの不変性ではなく 凝縮された物質のフェルミオンを支配し 新しい種類の興奮を可能にします
研究 の 目的:
- 新しいフェルミオン刺激を調査する
- 従来のディラック・ウェイル・マジョラナ・フェルミオン分類を超えて
- 非従来のフェルミオンの研究のための材料プラットフォームを特定する.
主な方法:
- 角解像度光放出スペクトロスコーピー (ARPES)
- 電子帯域構造の実験的検証
- クリスタル電子構造の変性点の分析
主要な成果:
- 結晶性モリブデン・フォスフィードに3重変性点があることが示された.
- この点の近くの準粒子刺激として3つの成分フェルミオンを特定し,ディラック,ウェイル,マジョラーナを超えた新しいクラスです.
- 散発電子構造で共存するウェイル点のペアを観測した.
結論:
- モリブデン・フォスフィードは新しい3つの成分フェルミオンを宿し,フェルミオン分類を拡張します.
- この材料は,異なるフェルミオンタイプの相互作用を研究するためのプラットフォームとして機能します.
- この発見は 非伝統的なフェルミオンの 新しい物理学の探索の道を開きます
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