Quasi-monoenergetic ultrashort microbunch electron source

By combining static electric and laser fields for generation of field-emitted electrons, it is possible to generate a quasi-monoenergetic train of electron microbunches by controlling the anode-cathode spacing such that the time of flight of the electrons becomes independent of the laser field. Such quasi-monoenergetic microbunches with pulse durations that are a fraction of the laser wavelength would be ideal for radiation sources as well as compact accelerators.