飞秒强激光与气体介质相互作用可以辐射出高次谐波(HHG),能够提供一种重要的极紫外(EUV)相干光源,是原子分子物理[1-3]、生物医学[4]、材料化学[5-6]、精密光谱计量学[7]等基础科学领域中不可或缺的工具。 气体高次谐波的产生可以用半经典的三步模型[8]来解释:气体原子或分子在强激光场的作用下首先发生隧穿电离产生自由电子;然后自由电子在激光场中加速并获得能量;最后自由电子同母离子结合并释放出阿秒量级脉冲宽度的高次谐波极紫外辐射。 一方面,高次谐波最大光 …

2018年9月13日 · Intense, coherent HHG from four different liquids has been observed up to 20 eV, showing promise as an alternative source of coherent EUV radiation that combines the advantages of both gas and...

目前ASML的EUV光源产生方法是laser-produced plasma，有人可以介绍一下具体的机理吗？这个laser-produced…

Unique feature of HHG-XANES: Simultaneous exposure and spectrally resolved absorption spectroscopy in the XUV with chemical sensitivity. Objective: Measure exposure kinetics as function of dose in photoresists. Measure the complex dynamics in materials relevant for EUV lithography and understand how to improve them. HHG target sample XUV pulse ...

Fully spatially coherent 13.5-nm harmonic beam(59th of 800-nm pump laser beam) is best EUV source for EUV mask metrology. To achieve spatial coherence, synchrotron used pinhole. Shot-to-shot source position stability will be improved by quad-photodiode and automatic mirror stages.

coherent EUV radiation for metrology • EUV-based metrology is a potentially interesting tool for litho applications • The broad bandwidth of HHG sources allows spectroscopic characterization (identification) of materials • Spectrally resolved lensless EUV imaging is possible through coherent diffractive (lensless) imaging techniques

2002年7月19日 · Prof. David Attwood / UC Berkeley EE213 & AST210 / Spring 2009 14_HHG_2009.ppt The HHG Process 1.A high electric field of a coherent, intense laser pulse liberates a core electron from the atom. 2.The electron is accelerated in the laser field. 3.The electron recombines with the atom (ion) in a very short

Learn the physics of HHG by clicking here. XUUS 5 upconverts ultrafast laser pulses into the Extreme UV (EUV or XUV) or soft X-ray regions of the spectrum. Employing HHG processes, the output beam inherits the coherent properties of a driving laser such as the KMLabs RAEA with wavelengths that can be tuned from ~10 to 50 nm.

2014年9月14日 · High photon flux with up to 1012 photons in the 25–40 eV range has been achieved in a new table-top coherent extreme ultraviolet (EUV) source based on phase-matched high-harmonic generation ...

The HHG & EUV Science group focuses on the studies and development of coherent EUV/soft-X-ray sources based on the high-harmonic generation process with femtosecond/attosecond time and nanometer spatial resolution for spectroscopy, imaging, and metrology applications.