在光激发的GeTe中,第一阶段的向立方相转换
Matteo Furci1, Giovanni Marini2, Matteo Calandra1,2,3
1Department of Physics, University of Trento, Via Sommarive 14, 38123 Povo, Italy.
Physical review letters
|June 21, 2024
概括
光激发的 telluride (GeTe) 过渡到一个新的阶段没有加热,由间隙关闭驱动,而不是声软化. 超快的X射线衍射证实了相变材料中的这种第一阶段相变.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- telluride (GeTe) 呈现出由光诱导的非热相过渡,从形结构转变为岩盐结构.
- 这种转变的潜在微观机制和特征仍然不完全理解.
研究的目的:
- 阐明光激发的GeTe中非热相变的机制.
- 为了区分非热过渡和热过渡.
- 为了使理论预测与实验观测相协调.
主要方法:
- 约束密度功能扰动理论. 约束密度功能扰动理论.
- 随机自相一致的和近似来包括量子无和.
- 对超快X射线衍射数据的分析.
主要成果:
- 在GeTe中,非热相过渡具有强烈的第一顺序,与热相过渡形成鲜明对比.
- 波软化并没有驱动非热过渡.
- 过渡是由光刺激诱导的单粒子间隙在面相中的关闭启动的.
- 实验数据支持阶段共存,与第一阶段过渡相一致.
结论:
- 这项研究阐明了Ge.Te.中的非热相转换的独特机制.
- 它强调了电子激发和差距关闭对晶格振动的作用.
- 结果提供了关于相变材料的结合和相变的见解.
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