Blazed Nanostructure Gratings for Electron and Atom Diffraction

Nanofabricated transmission gratings for electron diffraction are now available [1, 2] and may serve as coherent beam splitters for electron interferometry just as they already do for atom interferometry. For electron beams with kinetic energy less than 10 keV, nanostructures offer several advantages over solid crystal gratings, for example larger transmission, less inelastic scattering, and the possibility of engineering blazed diffraction gratings. Blazed gratings enhance the intensity of a particular diffraction order, and can be used to make more efficient beam splitters for interferometry. To design a blazed nanostructure grating, we must first understand and then control the phase shifts for matter waves that are caused by interactions with the nanostructure. To learn how different interactions (e.g. image charge or van der Waals potentials) affect the design, here we compare electron and atom diffraction from similar nanostructures. With simulations we show how phase shifts can lead to asymmetric diffraction patterns, and we present electron and atom diffraction data that supports this theory.