Attosecond Soft X-ray Spectroscopy of Condensed Phase Matter

凝聚相物质的阿秒软X射线能谱

• 批准号: 1994329
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1994329
• 关键词: Attosecond; Soft; ray; Spectroscopy; Condensed

The project will extend the technique of attosecond X-ray absorption spectroscopy to condensed phase materials. This will require further optimization of the required optical sources i.e. both the "pump" which are few-femtosecond long pulses in the visible to deep UV range, and the "probe" which are soft X-ray isolated attosecond pulses in the 100 - 500 eV photon energy range. For the former the research will focus on using non-linear optical methods to efficiently generate low order (up to 9th) of few-cycle pulses in the visible-NIR region. For the latter the present source, based on HHG of MIR few-cycle pulses in high density gas jets, will be enhanced by the use of optimized gas jet design and improved X-ray transmission through the beamline. With this capability we will measure exciton dynamics in organic polymers and organic oligomers in liquid phase to better understand fundamental issues of decoherence and transport of excitons in these materials. The role of polymer structure and morphology of the samples will be systematically explored. In this way not only will the research further the tools of ultrafast X-ray measurement, but may also contribute to the understanding of important materials in polymer opto-electronics that are currently used in solar energy harvesting research.

该项目将把阿秒X射线吸收光谱技术扩展到凝聚相材料。这将需要进一步优化所需的光源，即“泵浦”和“探测”，“泵浦”是可见光到深紫外范围内的几飞秒长脉冲，“探测”是100 - 500 eV光子能量范围内的软X射线隔离阿秒脉冲。对于前者的研究将集中在使用非线性光学方法，有效地产生低阶（高达9）的几个周期的脉冲在可见光-近红外区域。对于后者，本源，基于HHG的MIR几个周期的脉冲在高密度气体射流，将通过使用优化的气体射流设计和改进的X射线透射通过束线增强。有了这种能力，我们将在液相中测量有机聚合物和有机低聚物中的激子动力学，以更好地理解这些材料中激子的退相干和传输的基本问题。将系统地探讨聚合物结构和样品形态的作用。通过这种方式，研究不仅将进一步发展超快X射线测量工具，而且还可能有助于理解目前用于太阳能收集研究的聚合物光电子学中的重要材料。