Micro-low energy electron diffraction (μLEED) is a powerful tool that is widely used for probing local surface structural features. Scanning μLEED in cooperating with low energy electron microscopy (LEEM) provide surface demographic information in real space with regional (250 nm) reciprocal space overlay on top. Such method provides precise quantitative information on structural variations with high spatial resolution. We propose an automatic high throughput method, Source Extraction and Photometry (SEP) ‒ Spot Profile Analysis (SPA), to analyse large data set from scanning μLEED. SEP-SPA ability to automatically identify and analyse diffraction peaks opens up the possibility to investigate complex system with small domain size and random domain orientation, which diffraction p...[ Read more ]

Micro-low energy electron diffraction (μLEED) is a powerful tool that is widely used for probing local surface structural features. Scanning μLEED in cooperating with low energy electron microscopy (LEEM) provide surface demographic information in real space with regional (250 nm) reciprocal space overlay on top. Such method provides precise quantitative information on structural variations with high spatial resolution. We propose an automatic high throughput method, Source Extraction and Photometry (SEP) ‒ Spot Profile Analysis (SPA), to analyse large data set from scanning μLEED. SEP-SPA ability to automatically identify and analyse diffraction peaks opens up the possibility to investigate complex system with small domain size and random domain orientation, which diffraction peak positions alter rapidly with respect to small spatial displacement. A defective graphene on Cu(111) is used to demonstrates SEP-SPA capabilities. The sample is found to have rich rotational domain structure with majority of the graphene is co-aligned with the Cu(111) substrate.

A simulation of the extended Fourier Optics (FO) approach is presented. Using commercial cloud infrastructure, a low-cost high-performance method is proposed. One-dimensional (1D) and two-dimensional (2D) in aberration-corrected (ac) and uncorrected (nac) LEEM of different phase objects' numerical simulation results are presented. A set of phase objects under different defocus condition in new 1DFO simulation approach are benchmarked against previously published result. The implementation of a multi-core, multi-threading programming architecture in cloud provides significant time and cost saving. This work paves the way for an iteration approach to understand and construct three-dimensional mapping using two-dimensional LEEM defocus image series.