用于XUV超快光源单色化的高效低密度光栅装置
An efficient low-density grating setup for monochromatization of XUV ultrafast light sources
摘要：
超快光源已成为材料科学中获取和理解瞬态现象不可或缺的工具。然而，一种简单且易于实现的谐波选择方法，具有高传输效率和脉冲持续时间守恒，仍然是一个挑战。在这里，我们展示和比较两种方法选择所需的谐波从高谐波产生源，同时实现上述目标。第一种方法是将极紫外球面镜与透射滤光片相结合，第二种方法使用垂直入射球面光栅。这两种解决方案的目标时间和角度分辨的光电子能谱与光子能量在10-20 eV的范围内，但相关的其他实验技术以及。这两种方法的特点是谐波选择的聚焦质量，效率和时间展宽。它表明，聚焦光栅是能够提供更高的透射率相比，反射镜+过滤器的方法（3.3倍高10.8 eV和12.9倍高18.1 eV），只有轻微的时间展宽（6.8%的增加）和一个有点大的斑点大小（约30%的增加）。总的来说，我们的研究建立了一个实验的角度之间的权衡一个单一的光栅法向入射单色器的设计和使用的过滤器。因此，它提供了一个基础，选择最合适的方法，在各种领域中，一个易于实施的谐波选择高谐波产生是必要的。
英文摘要：
Ultrafast light sources have become an indispensable tool to access and understand transient phenomenon in material science. However, a simple and easy-to-implement method for harmonic selection, with high transmission efficiency and pulse duration conservation, is still a challenge. Here we showcase and compare two approaches for selecting the desired harmonic from a high harmonic generation source while achieving the above goals. The first approach is the combination of extreme ultraviolet spherical mirrors with transmission filters and the second approach uses a normal-incidence spherical grating. Both solutions target time- and angle-resolved photoemission spectroscopy with photon energies in the 10-20 eV range but are relevant for other experimental techniques as well. The two approaches for harmonic selection are characterized in terms of focusing quality, efficiency, and temporal broadening. It is demonstrated that a focusing grating is able to provide much higher transmission as compared to the mirror+filter approach (3.3 times higher for 10.8 eV and 12.9 times higher for 18.1 eV), with only a slight temporal broadening (6.8% increase) and a somewhat larger spot size (~30% increase). Overall, our study establishes an experimental perspective on the trade-off between a single grating normal incidence monochromator design and the use of filters. As such, it provides a basis for selecting the most appropriate approach in various fields where an easy-to-implement harmonic selection from high harmonic generation is needed.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
