Atomic Resolution in Near-Edge Core-Loss Mapping Beyond the Conventional Delocalization Limit.

The spatial resolution of core-loss electron energy-loss spectroscopy (EELS) is limited by the delocalization of inelastic scattering from long-range Coulomb interactions, especially for light-element edges at low energy losses. Here we demonstrate atomic-resolution imaging of the Si L edge in Si [110] using dark-field annular EELS that selectively detects high-angle inelastic scattering. Although the intrinsic excitation delocalization remains unchanged, momentum-transfer-selective detection suppresses long-range contributions, enabling the 1.36 Å Si dumbbell to be resolved.