A hot electron, cold cathode, emitter

A hot electron, thin-film, cold-cathode device is described which has an emission efficiency much higher than previously reported for similar cathodes. Measurements of the emission current and distributionat various voltages indicate the importance of a coherent scattering process, which if not considered in the design of the cathode will severely limit the emission efficiency. The important conditions for a more efficient cold cathode are specified and discussed with respect to previous cold cathodes designed to surmount other loss processes which are shown to be of secondary importance to coherent scattering