在水晶五中激发子的phonon驱动的femtosecond动力学从第一原则开始
Galit Cohen1, Jonah B Haber2,3, Jeffrey B Neaton2,3,4
1Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel.
Physical review letters
|April 5, 2024
概括
兴奋子 - 声子散射是五纪中占主导地位的放松通路,由晶体异性质和纵横分裂驱动. 这项研究阐明了分子晶体中激电的非辐射寿命.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 非辐射刺激放松对于光电子材料的能量转移至关重要.
- 了解晶体结构,带结构 (电子,激子,声子) 和粒子相互作用之间的联系是复杂的.
研究的目的:
- 为了研究一个模型分子晶体 - - 五烯中的激子 - - 声子放松通路.
- 阐明晶体异质性和激子-声子相互作用在非辐射衰变中的作用.
主要方法:
- 第一原则计算.第一原则计算.
- 计算动量和带分辨率的刺激子 - 声子相互作用.
- 刺激子散射通道的分析.
主要成果:
- 激励子在带内和带间散射到暗状态发生在~100 fs的时间尺度上.
- 亮激子带的纵横分裂是一个关键因素.
- 兴奋子 - 声子散射被确定为在五纪中占主导地位的非辐射放松通道.
- 晶体异质性会影响激发波包的传播和波段的分散.
结论:
- 刺激子-声子相互作用显著影响分子晶体中的刺激子非辐射寿命.
- 这些发现为设计具有受控能量转移的光电子材料提供了一个框架.
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