Generation of a Periodic Sequence of Ultrashort Electromagnetic Pulses in a Scheme with Two Parallel Radiating and Absorbing Electron Beams

We demonstrate the possibility of generating a periodic sequence of ultrashort electromagnetic microwave pulses in a scheme with two parallel coaxial electron beams formed by a common cathode and transported via common vacuum channel. The external cylindrical tubular beam ensures the amplification of radiation during rectilinear propagation along periodic slow-wave system, while the internal (paraxial) beam accounts for the nonlinear cyclotron-resonance absorption.