Creating electron phase holograms using femtosecond laser interference processing

Recently, electron beams with structured phase fronts, such as electron vortex beams, have attracted considerable interest. Herein, we present a novel method of fabricating electron phase holograms using a femtosecond laser interference processing. A 35-nm-thick silicon membrane, corresponding to a phase shift of π for 200-keV electrons, was processed using single-shot laser irradiation, whereas processing such thin membranes with a focused ion beam milling technique would be very difficult. This rapid and efficient technique is expected to produce phase diffraction elements for practical applications in a wide range of electron optics fields.