Undulator-Like Radiation and N² Effects in Semiconductor Microstructures with Grating

In the article the cooperative N²-effects are considered, that is the radiation whose power is ım N², where N is the number of emitters which in this case is equal to the number of electrons in a bunch. The suggested effects are the result of combining two effects: the Gunn-effect in GaAs and undulator-like radiation, or "pumping wave" acting on the electrons and which is the result of undulator field, while the second is the backward effect of radiation which is produced by electrons moving within such microundulator. It is very probable that the effects can be used for the developing of a new semiconductor-based room temperature source of the THz-radiation.