Although the diffraction of electrons from crystals is a cornerstone of materials science established already a hundred years ago, the corresponding experiments with neutral atoms had not been reported. Researchers from the German aeronautics and space research centre (DLR) in collaboration with the group of Toma Susi now answer this challenge by demonstrating diffraction of helium and hydrogen atoms at kiloelectronvolt energies through single-layer graphene.
The Vienna contribution to these landmark results were the simulations that showed that even though the larger kinetic energies of the projectiles increase their energy loss, their extremely short interaction time when transiting the atomically thin crystal still made it possible to maintain coherent diffraction. While these simulations would have been barely possible before, the software tools developed as part of the FWF project CETHIS enabled the team to support the experimental work in a more comprehensive and effective manner. These also make it possible to investigate much more complex material combinations, including the intensively studied van der Waals heterostructures.
C. Kanitz et al., Science (2025) DOI:10.1126/science.adx5679
