International Collaboration in Chemistry: Control of Ultrafast EUV-induced Chemical Reactions

我们将研究超短时间延迟的EUV/IR光场对分子离子的形成和碎裂的控制。使用超快激光脉冲在真实的时间内跟踪并最终控制分子在激发后重排的反应途径是当今化学和物理学中常见的和大量研究的主题。最近的发展是通过高次谐波产生产生10-100 eV范围内的高能光子，其具有足够的通量，使得它们可以用作束以激发/激发宏观样品气体的可工作部分。这些光子的能量足以激发和激发分子。带双电荷的分子离子通常会分裂成带电碎片，综合动量成像技术（称为COLTRIMS，反应显微镜，TRCIS等1）可用于测量所有带电反应产物的完整动量矢量，包括离子和电子。在通过超短EUV脉冲脉冲产生激发的离子分子之后，可以使用第二强红外脉冲来操纵碎裂路径，该第二强红外脉冲的强度、波形和定时是控制参数。我们建议通过将一个机构（KSU）的动量成像专业知识与另一个机构（MPQ）的高次谐波生成专业知识相结合来研究这些过程。

We will investigate the control of the formation and fragmentation of molecular ions by ultrashort time delayed EUV/IR light fields. The use of ultrafast laser pulses to follow in real time, and ultimately control, the reaction pathways whereby a molecule rearranges after excitation is a common and heavily studied theme in chemistry and physics today. A recent development has been the production of energetic photons in the 10-100 eV range, through high harmonic generation, with sufficient fluxes that they can be used as a beam to excite/ionize workable fractions of a macroscopic sample gas. Such photons are energetic enough to both excite and ionize the molecule. A doubly charged molecular ion typically breaks into charged fragments, and comprehensive momentum imaging technologies (known variously as COLTRIMS, reaction microscope, TRCIS, etc. 1) are available for measuring the full momentum vectors of all charged reaction products, including both ions and electrons. Following the impulsive production of an excited ionic molecule by an ultrashort EUV pulse, the fragmentation pathway can be steered using a second strong infrared pulse whose intensity, waveform and timing are control parameters. We propose to study such processes by combining the momentum-imaging expertise of one institution (KSU) with the high harmonic-generation expertise of another (MPQ).