Optically excited field emitter arrays with plasmonic gate electrodes as ultrafast electron sources

In this paper, we propose to further optimize light coupling to field emitter nanotips by integrating gate electrodes that support excitation of surface plasmon polaritons at wavelengths of interest. The study indicates that the submicron arrays with the plasmonic gate electrodes can increase electron yield by 30 times and simplify experimental setup by allowing efficient excitation at normal incidence. By using an advantage of SPP generated on gate surface, optical excitation of the emitter tips is also possible for double gate field emitter arrays, where the second gate is used for electron beam collimation. This should create opportunities for development high charge ultrafast electron sources with superior brightness.