アルファ-およびベータ-A2Hg3M2S8 (A = K,Rb;M = Ge,Sn):強い非線形光学応答を有する極四極カルコゲニド
J-H Liao1, G M Marking, K F Hsu
1Department of Chemistry and Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824-1322, USA.
Journal of the American Chemical Society
|August 2, 2003
まとめ
新しいアルカリ金属硫化水銀化合物 (A2Hg3M2S8) は,ユニークな結晶構造と強力な非線形光学特性を有しています. これらのワイドギャップ半導体は,優れた熱安定性と高度なアプリケーションのための高いレーザーダメージの値を示しています.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
背景:
- 望ましい光学および電子特性を持つ新しい材料の発見は,技術的進歩にとって極めて重要です.
- アルカリポリカルコゲニド流量法により,新しい化合物の合成が可能になります.
- 極性非中心対称結晶構造は,非線形光学アプリケーションの鍵となる.
研究 の 目的:
- A2Hg3M2S8化合物の新しい相を発見し,特徴づけること.
- 結晶学,光学,熱学,非線形光学特性を調査する.
- ワイドギャップ半導体および非線形光学材料としての潜在能力を探求する.
主な方法:
- 結晶合成のためのアルカリポリカルコゲニド流量法.
- 構造的決定のための単結晶X線 difraktion.
- 光学スペクトル検査 (UV-Vis-NIR),熱分析 (TGA/DSC),および非線形光学 (SHG) 測定を行う.
主要な成果:
- 新しい構造型のアルファとベータA2Hg3M2S8 (A=K,Rb;M=Ge,Sn) 段階の発見.
- アルファ (オーソロンビック,Aba2) とベータ (モノクリニック,C2) 形態の正確な結晶学的データの決定.
- 広い帯域のギャップ (~2.40-2.64 eV),広範囲のIR透明性 (最大14μm),および高非線形係数 (β-K2Hg3Ge2S8のd_eff ~20 pm/V) の特徴付け.
結論:
- 新しく発見されたA2Hg3M2S8相は,独特の極性非中心対称構造を持っています.
- これらの材料は,強力なSHG応答により,非線形光学アプリケーションの有意な可能性を示しています.
- 幅広い帯域の隙間,熱的安定性,および頑丈性により,光電子機器の有望な候補となります.
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