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Experimental study on frequency doubling of Q-switched partially coherent laser


In this paper, we investigate the frequency doubling of Q-switched partially coherent laser pulses. Such laser pulses are generated using a neodymium-doped yttrium aluminum garnet laser in which the laser cavity is a degenerate resonator. Electro-optic Q-switching is employed to generate laser pulses with a pulse width of approximately 10 ns. The spatial coherence of the output laser can be modulated by changing the size of a spatial filter within the laser cavity. The influence of spatial coherence on the conversion efficiency of the frequency doubling is studied. It is found that reducing the spatial coherence results in a slight reduction of the frequency-doubling conversion efficiency. However even in the case of low spatial coherence, the frequency-doubling conversion efficiency remains high, larger than 30%. The partially coherent laser beams with high frequency-doubling conversion efficiency can be applied to laser imaging, laser illumination, and inertial confinement fusion (ICF), etc.

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This work was support by Dongguan Introduction Program of Leading Innovative and Entrepreneurial Talents (China).

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Correspondence to Jixiong Pu.

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Wang, K., Wang, Y., Zhang, G. et al. Experimental study on frequency doubling of Q-switched partially coherent laser. Opt Rev 29, 172–177 (2022).

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  • Partially coherent laser
  • Q-switched
  • Frequency doubling
  • Degenerate resonator