At the 17th European Vacuum Conference (EVC-17)/37th European Conference on Surface Science (ECOSS-37) held in Harrogate, UK, June 16-21, 2024, Dr. Rezwan Ahmed, Postdoctoral Researcher at the Slow Positron Facility, Institute of Materials Structure Science, received the Early Career Researcher (ECR) Poster Award. The awards ceremony took place during the closing session on June 24.
In his poster titled "Report on New Findings in Low-Energy Positron Diffraction (LEPD) Experiments for Surface Structure Analysis", Rezwan presented characteristics of the substantially upgraded low-energy positron diffraction (LEPD) station at the Slow Positron Facility, as well as the I-V curve data for the Cu(001) surface measured to evaluate the performance of the apparatus and the surface structure analysis. LEPD is the positron counterpart of low energy electron diffraction (LEED), a method for structural analysis (precise determination of atomic arrangement) of a few atomic layers of a surface.
Thanks in part to parallel improvements in beam transport, LEPD patterns for each energy can be obtained in one minute, and the acquisition of diffraction patterns required for structural analysis of a single surface can be completed in about two hours. The analysis was performed in a program widely used in LEED, changing only the sign of the charge of the incident particles. It has been revealed that surface sensitivity of LEPD is higher than that of LEED, and the agreement between measured and theoretical I-V curves is much better than that of LEED.
These attracted the attention of many participants, and the award was highly commended.
