Modelling of the Effects of KDP Crystal Gravity Sag on Broadband Third Harmonic Generation via Multi-Crystal Design
K. Jia, X. Pan, X-D. Yuan, K-H. Cui and B. Zhang
Two kinds of broadband lasers (the temporal phase modulation (TPM) laser and the chirped pulse stacking (CPS) laser) and mounting configurations (the full edges support and the silicone fixed scheme) have been used to analyse the effects of the gravitational sag on the broadband third harmonic conversion efficiency via multi-crystal design. The result shows that the multi-crystal design can improve the broadband third harmonic generation (THG) efficiency and the THG efficiency of the TPM laser is slightly larger than that of the CPS laser when the spectral bandwidth is relatively narrow, whereas the situation is reversed if the spectral bandwidth becomes broader. Meanwhile, considering the gravitational sag, the full edges support is benefit for the TPM laser within the bandwidth range of 150 to 300 GHz and for the CPS laser within the range of 250 to 400 GHz.
Keywords: Broadband laser, temporal phase modulation (TPM) laser, chirped pulse stacking (CPS) laser, inertial confinement fusion, multi-crystal design, third harmonic generation (THG), surface deformation