Experimental Studies of 75 GHz Relativistic Surface-Wave Oscillator of Planar Configuration

Based on three-dimensional particle-in-cell modeling results experimental studies of a W-band surface-wave oscillator powered by a ribbon high-current relativistic electron beam produced by SINUKI accelerator (Federal Research Center Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, 1 kA / 650 keV / 17 ns) were carried out. Efficient mode selection along a wide transverse coordinate was demonstrated by using an open planar waveguide with Fresnel parameter of 5. A stable regime of single-mode narrow-band generation is experimentally obtained. The output power measured by the calorimetric method reaches 25 MW. The radiation spectrum is measured based on the heterodyne scheme and the central frequency is 75 GHz.