Research on solid-state lasers with adjustable pulse width based on the controllable release of the inverted population

A laser with an adjustable pulse width is very important for laser processing and scientific research. In this study, we propose a theoretical model to adjust laser pulse width by controlling the diffraction loss of the resonator cavity in an acousto-optic Q-switched solid-state laser system. The varies of the diffraction loss are in accordance with a set function, then modulating the release of the inverted population. Analyzing the impact of the diffraction loss function in the process of inverted particle release, we determined the dividing line of control parameters that distinguish normal modulation and pulse distortion and obtained the optimal adjustment parameters. The method and theoretical model were verified by experiment, resulting in a pulse width adjustment range of 27 ns to 62 ns under fixed resonator structure and pumping rate conditions. An adjustable pulse width laser system utilizing the method has a simple laser resonant cavity, and the output pulse width can be adjusted in real-time.