Coherent Electron Control

相干电子控制

• 批准号: 2207697
• 负责人: Herman Batelaan
• 金额: $ 58.8万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2207697&HistoricalAwards=false
• 关键词: Coherent; Electron; Control

Classical Mechanics tells us how bridges, cars, and other objects in our everyday world at the macroscopic scale work. Quantum Mechanics tells us how electrons, atoms and other objects in the microscopic world work. We need to find a description of nature that works at the microscopic and macroscopic scales and everything in between. This is a century-old unsolved problem and is called the “Quantum Measurement Problem.” Not only do we want to solve the problem, but we want to use “quantumness” at a larger scale, and not understanding the problem stops us from doing this. To solve this problem, objects at an intermediate scale, in between the microscopic and macroscopic, need to be studied. This is what the project: “Coherent Electron Control” is aiming to do. Microscopic objects, electrons, are placed close to an everyday world object, a wall, so that the description of how the two interact is neither described by Quantum Mechanics, nor Classical Mechanics. New models and theories can be tested in this way. On the practical side, the interaction between electrons and walls has been proposed to be the cause of what limits how well electron microscopes can see. The nearby electron microscope walls destroy the useful quantum mechanical properties of the electrons. If this “decoherence” can be overcome, this may point the way to improving electron microscopes, a widely used scientific tool including in the field of nano-medicine. A second objective of the research team is to look at the “quantumness” of a group of electrons close to each other. This situation exchanges the electron interaction with the wall for the interaction between an electron and electron. It is predicted that this quantumness can be used to further improve the resolution of electron microscopes. The research project will provide experience to postdocs, graduate students, undergraduate students and high school students in quantum science, which is an area of national need. Patents, based on the technologies being developed, will be pursued and will potentially contribute to the national economy.Electron diffraction from nanofabricated gratings will be used to split electron beams coherently into two parts. Walls will be placed close to the electron beams to partially decohere the electron beams. The electron beams are recombined and the measured amount of quantum mechanical interference tells us about the amount of decoherence. A femtosecond laser will be used to extract multiple electron from a nanotip, that is, make an electron pulse. This will ensure that the electrons are close enough together to interact. The research team will search for a quantum mechanical signature called the Hanbury-Brown Twiss effect by controlling the time duration, the size, and the polarization of the electron pulse.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

经典力学告诉我们，我们日常生活中的桥梁、汽车和其他物体在宏观尺度上是如何工作的。量子力学告诉我们电子、原子和其他微观世界中的物体是如何工作的。我们需要找到一种对自然的描述，它适用于微观和宏观尺度，以及介于两者之间的一切。这是一个百年未解的难题，被称为“量子测量问题”。我们不仅想解决这个问题，还想在更大的范围内使用“量子”，而不理解这个问题会阻止我们这样做。为了解决这个问题，需要研究介于微观和宏观之间的中间尺度的物体。这就是“相干电子控制”项目的目标。微观物体——电子——被放置在日常世界物体（一堵墙）附近，因此，对两者如何相互作用的描述既不是量子力学所描述的，也不是经典力学所描述的。新的模型和理论可以通过这种方式得到检验。在实际应用方面，电子和壁之间的相互作用被认为是限制电子显微镜观察效果的原因。附近的电子显微镜壁破坏了电子有用的量子力学特性。如果这种“退相干”能够被克服，这可能会为改进电子显微镜指明道路，电子显微镜是一种广泛使用的科学工具，包括在纳米医学领域。研究小组的第二个目标是观察一组相互靠近的电子的“量子化”。这种情况将电子与壁的相互作用转换为电子与电子之间的相互作用。预测这一量子量可用于进一步提高电子显微镜的分辨率。该研究项目将为博士后、研究生、本科生和高中生提供量子科学方面的经验，这是一个国家需要的领域。将以正在开发的技术为基础寻求专利，并可能对国民经济作出贡献。来自纳米光栅的电子衍射将被用来将电子束相干地分裂成两部分。在靠近电子束的地方放置墙壁，使电子束部分退相干。电子束被重新组合，量子力学干涉的测量量告诉我们退相干的量。飞秒激光将用于从纳米尖端提取多个电子，即制造一个电子脉冲。这将确保电子足够近地相互作用。研究小组将通过控制电子脉冲的持续时间、大小和极化来寻找一种被称为Hanbury-Brown Twiss效应的量子力学特征。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。