Lowe Morgan, Alkoby Yosef, Chadwick Helen, Alexandrowicz Gil
Department of Chemistry, Faculty of Science and Engineering, Swansea University, Swansea, SA2 8PP, UK.
Nat Commun. 2024 Aug 15;15(1):7046. doi: 10.1038/s41467-024-51175-2.
The emerging technique of neutral beam microscopy offers a non-perturbative way of imaging surfaces of various materials which cannot be studied using conventional microscopes. Current neutral beam microscopes use either diffractive focusing or pin-hole scanning to achieve spatial resolution, and are characterised by a strong dependence of the imaging time on the required resolution. In this work we introduce an alternative method for achieving spatial resolution with neutral atom beams which is based on manipulating the magnetic moments of the beam particles in a gradient field, and is characterised by a much weaker dependence of the imaging time on the image resolution. The validity of the imaging approach is demonstrated experimentally by reconstructing one dimensional profiles of the beam which are in good agreement with numerical simulation calculations. Numerical simulations are used to demonstrate the dependence of the signal to noise on the scan resolution and the topography of the sample, and assess the broadening effect due to the spread of velocities of the beam particles. The route towards implementing magnetic encoding in high resolution microscopes is discussed.
新兴的中性束显微镜技术提供了一种对各种材料表面进行成像的非侵入性方法，而这些材料是传统显微镜无法研究的。当前的中性束显微镜使用衍射聚焦或针孔扫描来实现空间分辨率，其特点是成像时间强烈依赖于所需的分辨率。在这项工作中，我们介绍了一种利用中性原子束实现空间分辨率的替代方法，该方法基于在梯度场中操纵束粒子的磁矩，其特点是成像时间对图像分辨率的依赖性要弱得多。通过重建与数值模拟计算高度吻合的束的一维轮廓，实验证明了成像方法的有效性。数值模拟用于证明信噪比与扫描分辨率和样品形貌的关系，并评估束粒子速度扩散引起的展宽效应。还讨论了在高分辨率显微镜中实现磁编码的途径。
