Intracavity holographic gratings and lasers with controllable spectrum based on them

A comparison is made of the effect of intracavity spectral selectors: static Bragg gratings and dynamic gain gratings. It is shown that their influence on the spectral properties of laser radiation with a loop resonator is similar. The performed statistical study of the mode composition of the trains of lasing pulses in the Q-switching mode allows us to conclude that overwriting the grating with the next pulse of the train does not prevent radiation at the same frequency. This opens up the possibility of frequency stabilization of radiation. The presence of an intracavity Bragg grating leads to an increase in the probability of maintaining the radiation frequency in adjacent pulses of the radiation train. It is shown that a narrowing of the pulse generation spectrum in the train is observed despite the fact that the spectral width of the grating exceeds the spectral width of the generation pulse. The joint operation of static and dynamic intracavity gratings makes it possible to create a line of lasers with high pulse energy, beam quality close to the diffraction limit, high peak power, and a narrow radiation spectrum.