固有のラットラー誘発低熱伝導性 シンタル型 TlInTe2
Manoj K Jana, Koushik Pal, Avinash Warankar1
1Department of Chemistry, Indian Institute of Science Education and Research (IISER) , Pune 411008, India.
Journal of the American Chemical Society
|March 7, 2017
まとめ
タリウムインジウムディテルリド (TlInTe2) は,タリウムカチオンの振動による超低熱伝導性を示す. この独特の格子ダイナミクスは 高度な熱電気材料の設計に 鍵となるものです
科学分野:
- 材料科学
- 固体物理学
- 凝縮物質物理学
背景:
- 化学結合と格子ダイナミクスを理解することは,超低熱伝導性を有する結晶固体の設計に不可欠です.
- このような材料は熱電学のようなアプリケーションに不可欠です.
研究 の 目的:
- タリウム・インジウム・ディテルリド (TlInTe2) の低熱伝導性を調査する.
- フォノン輸送におけるタリウムカチオンの振動の役割を解明する.
主な方法:
- 熱容量とTHz時間領域のスペクトロスコピーを含む実験的な測定.
- 結合,格子ダイナミクス,およびフォノン相互作用を分析するための第一原理計算.
主要な成果:
- TlInTe2は特異的に低いグリッドの熱伝導性 (約. 0.5 W/mK) 室温近くにある.
- 弱い結合のT kationsは,静電反発によって駆動されるc軸に沿って振動するダイナミクスを示します.
- 低周波のアインシュタインモードは,Tlの鳴き声と関連している.
- 最初の原理の計算は,T-ラッターの振動と音響フォノンの間の強い結合を明らかにした.
結論:
- TlInTe2の超低熱伝導性に起因する主なメカニズムは,Tl cationsの振動力学です.
- この研究は,ホーノン輸送メカニズムについて, 振動するゲスト原子を持つ物質に洞察を与えます.
- この発見は,振動誘発のフォノン散乱に基づく新型熱電気材料の設計を支持する.
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