Experimental Analysis of Beam Perturbation in a Planar Crossed-Field Structure

An experimental setup has been developed to perform experiments on a planar, crossed electric and magnetic field or crossed-field (CF) device. The structure, which is 15 cm long and 10 cm wide with an anode-to-sole gap of 2 cm, can measure electron beam perturbation as a function of injected beam current and magnetic field. The applied maximum anode to sole voltage is 3 kV and the applied maximum magnetic field is 0.02 T. A beam-measurement system, which consists of an anode with eight segmented sections and nine segmented end collectors, is incorporated. Eight silicon-gated field emitter arrays (Si-GFEAs) are used for the electron source. For the experiment, 1.5 mA of injected current at 50-V pulse was used. Experimental results without an applied magnetic field and with a magnetic field with different tilts are compared with simulation results and 1-D theory. The experimental planar crossed-field configurations demonstrate electron stability thresholds in current density and magnetic field tilt that agree with theory and simulation.