New oscillation mechanisms in avalanche diodes

The build-up processes of harmonically related modes from a silicon avalanche diode and the behavior of the simultaneous presence of these modes have been observed. We conclude that the lowest frequency mode (which had been regarded as the subharmonic mode) is the fundamental mode rather than the subharmonic mode. The output powers of these modes are related to each other because of feedback through the parametric effects or pumping by the second harmonic. Various superimposed mechanisms have been investigated, and the build-up processes are demonstrated in an animation film. A very stable oscillator has been obtained at 43 GHz with a diode that avalanched at a relatively low voltage of 12 volts.