LIQUID-PHASE ULTRAFAST ELECTRON DIFFRACTION

NSERC-RTI的资金支持对于升级我们自制的高能超快电子衍射仪（UED）至关重要，在本文中称为Waterloo-UED。升级涉及购买高精度负极性150千伏高压电源（HVPS）和真空系统，这是制造两级直流（DC）直线加速器和内部泄漏检查站附件所必需的。 两级直流直线加速器对于实现稳定的300 kV运行条件至关重要，同时确保我们实验室空间的辐射水平不超过平均背景水平。高能（>250 keV）电子是必须的，以便穿过亚微米厚的液体层而不会丢失信息。我们已经开发并测试了专有的纳米流体单元（NFC）系统，该系统将提供所需的300 nm厚的液体层（夹在25 nm厚的透明窗口之间），以成功进行液相UED测量。 为了强调这一升级的重要性及其科学影响，滑铁卢大学（即，300-keV超短电子爆发）和我们专有的NFC系统将首次在实验室环境中研究液相超快结构现象，并使我们与斯坦福大学直线加速器中心（SLAC-UED）的兆电子伏UED设施直接竞争。SLAC-UED是目前世界上唯一有能力进行液相UED实验的设施。 因此，我的实验室将是加拿大唯一一个拥有进行液相UED所需基础设施的实验室，这一要求将启动其向高能液相UED设施的转变，该设施将通过与SLAC-UED实施的管理计划类似的管理计划提供给加拿大研究人员。在SLAC-UED波束时间分配给用户在评估和批准的研究建议后，免费。Waterloo-UED和该仪器支持的研究计划液相UED是HQP最完整的培训计划之一的一部分（详见建议书）。仅从我的小组，平均2 PDF，5博士，和2硕士学位每度周期将利用滑铁卢UED除了其他几个外部用户一旦我的实验室开放作为加拿大设施（约。2023年年中）。

NSERC-RTI funding support is critical to upgrade our homemade high-energy ultrafast electron diffractometer (UED), herein referred to as Waterloo-UED. The upgrade involves the purchase of a high precision negative polarity 150-kV high voltage power supply (HVPS) and a vacuum system, which are necessary to fabricate a two-stage direct current (DC) linear accelerator and a leak check station attachment in house. The two-stage DC linear accelerator is crucial to enable stable 300-kV operation conditions while ensuring that the level of radiation in our laboratory space does not exceed the average background level. High-energy (>250 keV) electrons are a must in order to traverse a sub-micron thick liquid layer without facing loss of information. We have already developed and tested the proprietary nanofluidic cell (NFC) system that will confer the required 300-nm thick liquid layer (sandwiched between 25-nm thick transparent windows) to succeed with liquid-phase UED measurements.  To stress the importance of this upgrade and its scientific impact, the combination of Waterloo-UED (i.e., 300-keV ultrashort electron bursts) and our proprietary NFC system will enable the study of liquid-phase ultrafast structural phenomena in a laboratory setting for the very first time and place us in direct competition with the mega electron volt UED facility of the Stanford Linear Accelerator Center (SLAC-UED). SLAC-UED is currently the only facility in the world with capabilities to carry out liquid-phase UED experiments. Thus, my laboratory will be the only one in Canada with the required infrastructure to perform liquid-phase UED and this request will initiate its transformation into a high-energy liquid-phase UED facility that will be made available to Canadian researchers via a similar management scheme to the one implemented at SLAC-UED. At SLAC-UED beam time is assigned to users at no cost after the evaluation and approval of research proposals. Waterloo-UED and the research program that this instrument supports, liquid-phase UED, are part of one of the most complete training programs for HQP (see proposal for details). From my group alone, an average of 2 PDFs, 5 PhDs, and 2 MScs per degree cycle will utilize Waterloo-UED in addition to several other external users once my laboratory opens as a Canadian facility (ca. mid-2023).