Bergin M, Lambrick S M, Sleath H, Ward D J, Ellis J, Jardine A P
The Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE, UK.
Sci Rep. 2020 Feb 6;10(1):2053. doi: 10.1038/s41598-020-58704-1.
Scanning helium microscopy is an emerging form of microscopy using thermal energy neutral helium atoms as the probe particle. The very low energy combined with lack of charge gives the technique great potential for studying delicate systems, and the possibility of several new forms of contrast. To date, neutral helium images have been dominated by topographic contrast, relating to the height and angle of the surface. Here we present data showing contrast resulting from specular reflection and diffraction of helium atoms from an atomic lattice of lithium fluoride. The signature for diffraction is evident by varying the scattering angle and observing sharp features in the scattered distribution. The data indicates the viability of the approach for imaging with diffraction contrast and suggests application to a wide variety of other locally crystalline materials.
扫描氦显微镜是一种新兴的显微镜技术，它使用热能中性氦原子作为探测粒子。极低的能量以及不带电荷赋予了该技术研究精细系统的巨大潜力，以及产生几种新的对比度形式的可能性。迄今为止，中性氦原子图像主要由与表面高度和角度相关的地形对比度主导。在此，我们展示的数据表明，对比度源于氟化锂原子晶格对氦原子的镜面反射和衍射。通过改变散射角并观察散射分布中的尖锐特征，衍射的特征很明显。这些数据表明了利用衍射对比度进行成像方法的可行性，并暗示了其在多种其他局部晶体材料中的应用前景。
