Imaging the local density of electronic states by very low energy electron reflectivity

This work was concerned with the relationship between the reflectivity of very low energy electrons from a crystalline sample and its density of electron states above the vacuum level. Also, as different crystallographic orientations of the same single crystal exhibit different density of states, the usefulness of electron reflectivity at very low energies was demonstrated for the determination of crystallographic orientation. The technique chosen was the Scanning Low Energy Electron Microscopy (SLEEM) wich allows using arbitrarily low electron energies while preserving a very good image resolution. In our experiments, the incident electron energy ranged between 0 and 45 eV