マルチステートと相変化のポリモルフィズム K2Sb8Se13
Saiful M Islam1, Lintao Peng2, Li Zeng2
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|June 30, 2018
まとめ
K2Sb8Se13 (KSS) は,珍しい多形変異を呈する新しい材料であり,高度なコンピューティングと光学スイッチのために複数の安定状態を可能にします. この発見は 次世代の電子機器の扉を開きます
科学分野:
- 材料科学
- 固体化学
- 凝縮物質物理学
背景:
- フェーズチェンジ (PC) 材料は,バイナリ状態の可逆結晶変形を利用した光学データストレージに不可欠です.
- ポリモルフィズム,無形から無形への移行は,固体無機物質では非常に稀です.
研究 の 目的:
- K2Sb8Se13 (KSS) が多形と結晶の両方の相変異を示す物質として発見されたことを報告する.
- 複数の安定状態におけるKSSの特異な性質を記述する.
主な方法:
- K2Sb8Se13の可利用温度での相変遷を調査した.
- 異なるKSS状態の光学帯域と電気伝導性を分析した.
主要な成果:
- KSSは,それぞれ227 °Cと263 °Cで無形から無形の多形と無形から結晶への移行を示しています.
- この3つの状態 (無形I,無形II,結晶) は,環境条件下では安定している.
- 異なる光学帯域のギャップ (1.25,1.0,0.74 eV) と有意な導電性変化 (>2桁の大きさ) が各州で観察されました.
結論:
- KSSはポリアモルフィズムによる複数の安定状態を持つ新しい材料のクラスです.
- これらの特性は,マルチステート論理回路,再構成可能なデバイス,および高度な光学スイッチの開発に有望である.
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