Fast Hydrogen Atom Diffraction through Monocrystalline Graphene

We report fast atom diffraction through single-layer graphene using hydrogen atoms at kinetic energies from 150 to 1200 eV. High-resolution images reveal overlapping hexagonal patterns from coexisting monocrystalline domains. Time-of-flight tagging confirms negligible energy loss, making the method suitable for matter-wave interferometry. The diffraction is well described by the eikonal approximation, with accurate modeling requiring the full 3D interaction potential from density functional theory. Simpler models fail to reproduce the data, highlighting the exceptional sensitivity of diffraction patterns to atom-surface interactions and their potential for spectroscopic applications.