Unified ab initio description of the ultrafast reversible and irreversible laser-induced structural changes occurring in antimony: from coherent phonons up to nonthermal melting

锑中发生的超快可逆和不可逆激光诱导结构变化的统一从头描述：从相干声子到非热熔化

基本信息

批准号：
262778930
负责人：
Professor Dr. Martin Ezequiel Garcia
金额：
--
依托单位：
Theoretische Physik II: Festkörper und Ultrakurzzeitphysik
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2014
资助国家：
德国
起止时间：
2013-12-31 至 2020-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/262778930?language=en
关键词：
Unified ab initio description ultrafast

项目摘要

Femtosecond-laser pulses are known to create extreme nonequilibrium conditions in solids: Whereas the electrons are heated to several 10000 K, the ions remain close to room temperature. In this proposal we plan to perform, for the first time, a detailed study of the atomic pathways triggered by the changes in the bonding properties of solid antimony due to the laser excitation of hot electrons over a broad range of laser fluences up to the (nonthermal) melting threshold. Antimony is a particularly interesting material, since it is expected to exhibit all so far known laser-induced ultrafast structural phenomena, namely, coherent phonons, thermal phonon squeezing, solid-solid phase transitions, and nonthermal melting. In order to resolve the microscopic pathways followed by the atoms we intend to employ a molecular dynamics code based on Mermin's electronic-temperature-dependent density functional theory that has been recently written in our group. This so-called Code for Highly-excited Valence Electron Systems (CHIVES) uses local basis sets and order(N) methods for the construction of the Hamiltonian and overlap matrices and has been shown to be about two hundred times faster than state-of-the-art plane-wave codes. At present we can perform simulations of supercells with up to 1200 atoms. Ultrafast structural phenomena can be experimentally detected by all-optical pump-probe measurements of the reflectivity and more recently also directly using time-resolved electron- or x-ray-diffraction. Our analysis will yield time-dependent structure factors, which will, among other applications, be important for the interpretation of experiments planned at new x-ray free-electron-laser facilities, such as, FLASH in Hamburg and LCLS in Stanford.

已知飞秒激光脉冲在固体中会产生极端的非平衡条件：尽管电子被加热到几百k，而离子仍然接近室温。在此提案中，我们计划首次执行对原子途径的详细研究，该研究是由固体仇敌粘结性能变化而引起的，这是由于热电子激光激发在广泛的激光范围内的激光激发而引起的（非热）熔化阈值。锑是一种特别有趣的材料，因为预计它将展示到迄今为止所有已知的激光诱导的超快结构现象，即相干的声子，热声子挤压，固体固体相变和非热融化。为了解决微观途径之后，我们打算采用基于Mermin的电子 - 温度依赖性密度功能理论的分子动力学代码，该密度函数理论最近已在我们的组中写成。这种用于高度激发的价电子系统（CHIVE）的所谓代码使用局部基集和订单（n）方法来构建哈密顿量和重叠矩阵，并且已显示出比态度快两百倍艺术平面波代码。目前，我们可以对多达1200个原子的超级电池进行模拟。超快结构现象可以通过反射率的全光泵探针测量进行实验检测，并且最近也直接使用时间分辨的电子或X射线划分直接检测到。我们的分析将产生时间依赖的结构因子，除其他应用外，对于在新的X射线自由电子激光器设施中计划的实验，例如汉堡的Flash和Stanford的LCLS都很重要。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Quasimomentum-Space Image for Ultrafast Melting of Silicon.

硅超快熔化的拟动量空间图像

DOI：
10.1103/physrevlett.116.153901
发表时间：
2016
期刊：
Physical review letters
影响因子：
8.6
作者：
T. Zier;E. S. Zijlstra;M. E. Garcia
通讯作者：
M. E. Garcia

Ab initio molecular dynamics simulations of femtosecond-laser-induced anti-Peierls transition in antimony

飞秒激光诱导反 Peierls 转变为锑的从头算分子动力学模拟

DOI：
10.1117/12.2214668
发表时间：
2016
期刊：
影响因子：
0
作者：
E. S. Zijlstra;T. Zier;B. Bauerhenne;S. Krylow;M. E. Garcia
通讯作者：
M. E. Garcia

Coherent and incoherent structural dynamics in laser-excited antimony

激光激发锑的相干和非相干结构动力学

DOI：
10.1103/physrevb.95.054302
发表时间：
2017
期刊：
Physical Review B
影响因子：
3.7
作者：
L. Waldecker;Th. Vasileiadis;R. Bertoni;R. Ernstorfer;T. Zier;F. H. Valencia;M. E. Garcia;E. S. Zijlstra
通讯作者：
E. S. Zijlstra

Molecular dynamics simulations of a femtosecond-laser-induced solid-to-solid transition in antimony