高圧下における単元分子導体におけるディラック電子システムの出現
Reizo Kato1, HengBo Cui1, Takao Tsumuraya1,2
1Condensed Molecular Materials Laboratory, RIKEN , Wako-shi, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|January 26, 2017
まとめ
高圧下での単一成分分子導体 [Pd(dddt) ]で新しいディラック電子系が生じる. この発見は密度関数理論によって導かれ 分子材料のユニークな電子特性を明らかにしました
科学分野:
- 凝縮物質物理学
- 材料科学
- 固体化学
背景:
- シングルコンポーネントの分子導体には様々な電子状態があります.
- 新材料の設計には,圧力による電子相変化の理解が不可欠です.
研究 の 目的:
- シングルコンポーネント分子導体におけるディラック電子システムの出現を調査する.
- 高圧下でのディラク円形形成のメカニズムを解明する.
主な方法:
- 最初の原理の密度関数理論 (DFT) の計算.
- 緊密結合モデルを用いた分析
- 高圧実験条件 (12.6 GPa)
主要な成果:
- [Pd(dddt) 2の分子導体で12.6GPaでディラックコーンが確認された.
- 材料は温度に依存しない抵抗性を示し,ゼロギャップの振る舞いを示した.
- DFTの計算では,HOMOとLUMOのバンドが重なり合っていることが判明しました.
結論:
- 高圧は単元分子導体[Pd(dddt) ]にディラック電子系を誘導する.
- 電子帯の構造と分子層の相互作用が ディラック円の形成を統制する.
- この発見は,分子材料のトポロジック電子状態の探索に新しい道を開きます.
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