Modes Excitation in Diffraction Radiation Oscillator on High Space Harmonics of the Periodic Structure

The present report discusses experimental results obtained in an effort to compare the diffraction radiation oscillator operation features in the case of the excitation on the first, second and third space harmonics of the reflecting diffraction grating accommodated in the interior of the same open resonant system (ORS). It will be shown that a reasonable ORS choice provides the DRO excitation on the high-order space harmonics nearly without the starting current growth.