Single-longitudinal-mode acousto-optic Q-switched Nd∶YVO4 laser using Fabry-Perot etalon
Single-longitudinal-mode(SLM)lasers,characterized by their superior output laser beam quality,narrow linewidth,stable frequency,and compact size,find extensive applications in coherent optical communication,lidar,nonlinear optics,gravitational wave detection,and high-precision spectral measurement.A short cavity scheme in conjunction with Fabry-Perot etalon mode selection was employed,and a theoretical analysis of the longitudinal mode within the cavity was carried out.A laser diode single end-pumped acousto-optic Q-switched Nd∶YVO4 laser with a cavity length of 90 mm was involved,into which a 5 mm thick Fabry-Perot etalon with a reflectivity of 90%was inserted.A SLM laser output was realized with an adjustable repetition frequency of 1 Hz~10 Hz,a pulse duration of 10 ns,a single pulse energy of 133 μJ,and an energy instability of 3.39%.The output SLM laser was further amplified by two stages,and a single-pulse energy output of 40 mJ was obtained.