超快速的结构转变和电子-声/声-声合在中,由非adiabatic分子动力学揭示出来
Meng Niu1, Shun-Yao Qin1, Bai-Qian Wang1
1State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 130012 Changchun, People's Republic of China.
概括
超快激光激发激发的结构转换,一个相变材料. 控制激发强度可以平衡连贯和热运动,从而实现非挥发性结构变化.
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
- 计算化学的计算化学
背景情况:
- 换相材料在光激发时表现出超快的结构转变.
- 反 (Sb) 是一种典型的相变材料,表现出皮尔尔斯扭曲 (PD).
- 对于控制材料属性而言,了解非adiabatic动态是至关重要的.
研究的目的:
- 为了研究光诱导的结构转换在中超快的nonadiabatic动态.
- 阐明电子 - 声子和声子 - 声子合在这些转换中的作用.
- 确定实现非挥发性结构变化的条件.
主要方法:
- 实时时间依赖密度功能理论分子动力学 (rt-TDDFT-MD) 模拟.
- 分析电子-音声和音声-音声合的分析.
- 改变激发强度以观察不同的过渡行为.
主要成果:
- 随着激发强度的增加,在1ps内观察到三种不同的结构性过渡行为 (没有PD翻转,非挥发性PD翻转,不间断的前后翻转).
- 激发激活的连贯A1g声模式,由电子-声联驱动,启动结构过渡.
- 音频-音频合将连贯的运动能量转化为热能,防止持续的振荡.
结论:
- 非亚迪亚巴特电子 - 声和声 - 声的合在具有皮尔尔斯扭曲的材料中超快激光诱导的结构转换中至关重要.
- 适度的激发强度平衡了连贯和不连贯的热运动,导致非挥发性的PD翻转.
- 这些发现为光诱导物质结构和属性的操纵提供了洞察力.
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