Possibility of creating optical parametric oscillators with a precise shift of oscillation frequency, excited by monochromatic signal injection

The approximation of interacting quasi-monochromatic plane waves is used to analyse the possibility of parametric generation of pulses with a frequency shift relative to the injected monochromatic signal. This problem is important for the development of receiver – transmitters with heterodyne detection for remote IR spectroscopy of the atmosphere with a high spectral resolution and a long-range probing. Such systems can be fabricated on the basis of recently developed pulsed and cw optical parametric oscillators. The main attention is paid to the hitherto uninvestigated problem of nonadiabatic excitation of oscillations with a shift in the injected signal frequency relative to the cold resonator mode frequencies. It is shown that the oscillation frequency (frequencies) can be controlled upon such an excitation without increasing the spectral linewidth. The conditions for efficient excitation of single-frequency and two-frequency oscillations at adjacent resonator modes are found. Conditions for sufficient frequency stabilisation are determined.