Generation of cherenkov superradiant pulses with correlated phases defined by sharp edges of high-current electron bunches
Recently coherent summation of several SR pulses generated in parallel channels has been demonstrated in X- and Ka wavelength bands. This possibility is caused by picosecond stability of explosive emission from a cold cathode and strong correlation of phase of the SR pulses with respect to the leading edge of the electron bunch. In fact stimulated SR emission is initiated by spontaneous mission from bunch leading edges. In report we describe results of recent experiments and develop a theoretical model which covers both spontaneous and stimulated Cherenkov emission.
A coherent two-channel source of Cherenkov superradiance pulses
A two-channel source of Cherenkov superradiance pulses with the electron-wave systems of identical geometry which is capable of producing 2 × 0.3 GW pulses of duration 2 ns and center frequency 10 GHz has been developed and explored. The channels are powered by a high-voltage driver whose pulse is split into two pulses that are sent through parallel transmission lines. To shorten the voltage rise time in each channel, identical NiZn ferrite-loaded coaxial transmission lines with independently controlled axial bias fields are used.
Generation of gigawatt level beat waves
The initial experimental results of generating gigawatt level beat waves with two microwave sources are presented. The detailed measures for enhancing the power handling capacities of the applied devices are explained. In the experiments, the operation frequencies of the microwave sources are 9.41 GHz and 9.59 GHz, respectively. The microwave sources are driven by a single accelerator capable of producing dual electron beams to make sure that they are operating simultaneously. The beat frequencies, measured by the oscilloscope directly, are about 180 MHz, and the peak powers of the pulsed beat waves are about 4.3 GW with durations of about 40 ns.