Development of a Neutral Atom Microscope

中性原子显微镜的研制

• 批准号: 1704059
• 负责人: Mark Raizen
• 金额: $ 36万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-15 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1704059&HistoricalAwards=false
• 关键词: Development; Neutral; Atom; Microscope

Microscopes of various types are widely used in scientific research, medicine, and industry. The ability to see objects that are too small to see with the naked eye is crucial for characterizing materials, for manufacturing, and for forensic science. New capabilities in scientific research and technology are enabled by developing novel new microscopes with enhanced resolution and sensitivity. This project will explore ways to use focused atom beams to probe surfaces with nanometer-scale resolution. This addresses the longstanding goal in atomic physics of making a neutral atom microscope, similar to an electron microscope, but with different chemical sensitivity and less destructive interactions. An improved method to focus atom beams will be implemented using a pulsed magnetic lens. This aberration-corrected lens for atoms will enable the research team to pioneer applications for a neutral-atom microscope. The correction of aberrations is tremendously important for the performance of optical microscopes, and has enabled atomic scale resolution for electron microscopes. A breakthrough in aberration-corrected lenses for atoms will enable advances in atom lithography and the operation of a neutral atom microscope with molecular resolution. Students working on this project will gain training in atomic physics, atom optics, and surface chemistry research methods, and this will help prepare them for careers in universities and high tech industries.The principle of the microscope to be developed in this project is that neutral neon atoms in an excited metastable state are focused to a surface. After the impact of each atom, an electron is emitted which is energy-analyzed, providing a unique fingerprint of the chemical composition of the surface. The image will be acquired by rastering the atoms across the surface. The research team will use a pulsed electromagnetic coil as a lens for magnetic imaging of atoms. This allows for pulsed, high-current wires to exert a brief, strong focusing field on an atomic beam, taking advantage of the high refractive power without subjecting the atoms to fringing fields as they enter and leave the lens. Aberration correction will be achieved by tapering the lens to be narrower towards the front, thereby applying a greater force to the faster atoms. The pulsed lens is well-matched to a pulsed supersonic beam which produces a very bright beam of metastable neon atoms. The team has constructed a working prototype and plans to implement methods of beam brightening and velocity selection. With these improvements, a resolution better than 10 nm is expected. Further developments of the atomic lens will address residual aberrations. In parallel, the group will develop metastable impact electron microscopy using an analyzer system. Combining the two developments will enable demonstration of a neutral atom microscope with nanoscale resolution.

各种类型的显微镜广泛应用于科学研究、医学和工业领域。 能够看到肉眼无法看到的小物体对于表征材料、制造和法医学至关重要。 通过开发具有更高分辨率和灵敏度的新型显微镜，可以实现科学研究和技术的新能力。 该项目将探索使用聚焦原子束以纳米级分辨率探测表面的方法。 这解决了原子物理学的长期目标，即制造类似于电子显微镜的中性原子显微镜，但具有不同的化学敏感性和破坏性较小的相互作用。 将使用脉冲磁透镜来实施一种改进的聚焦原子束的方法。 这种像差校正原子透镜将使研究团队能够开拓中性原子显微镜的应用。 像差校正对于光学显微镜的性能非常重要，并且使电子显微镜能够实现原子级分辨率。原子像差校正透镜的突破将使原子光刻技术和具有分子分辨率的中性原子显微镜的操作取得进展。 参与该项目的学生将获得原子物理、原子光学和表面化学研究方法方面的培训，这将有助于他们为大学和高科技行业的职业生涯做好准备。该项目将开发的显微镜的原理是处于激发亚稳态的中性氖原子聚焦到表面。 每个原子撞击后，都会发射出一个电子，并对其进行能量分析，从而提供表面化学成分的独特指纹。 图像将通过在表面上光栅化原子来获取。 研究小组将使用脉冲电磁线圈作为原子磁成像的透镜。这允许脉冲、高电流线在原子束上施加短暂、强的聚焦场，利用高折光力，而不会使原子在进入和离开透镜时受到边缘场的影响。像差校正将通过使透镜朝前变窄来实现，从而对速度更快的原子施加更大的力。脉冲透镜与脉冲超音速束非常匹配，可产生非常明亮的亚稳态氖原子束。该团队已经构建了一个工作原型，并计划实施光束增亮和速度选择的方法。 通过这些改进，分辨率有望优于 10 nm。原子透镜的进一步发展将解决残余像差问题。 与此同时，该小组将使用分析系统开发亚稳态冲击电子显微镜。结合这两项进展将能够演示具有纳米级分辨率的中性原子显微镜。

项目成果

Monitoring damage of self-assembled monolayers using metastable excited helium atoms

使用亚稳态激发氦原子监测自组装单分子层的损伤

• DOI: 10.1063/5.0036827
• 发表时间: 2021
• 期刊: The Journal of Chemical Physics
• 作者: Stratis, Georgios;Zesch, Jordan D.;Pan, Henry S.;Webb, Lauren J.;Raizen, Mark G.
• 通讯作者: Raizen, Mark G.

Brightening of a supersonic beam of neutral atoms

中性原子超声束的增亮

• DOI: 10.1088/1402-4896/aae716
• 发表时间: 2018
• 期刊: Physica Scripta
• 影响因子: 2.9
• 作者: Anciaux, E;Stratis, G;Raizen, M G
• 通讯作者: Raizen, M G