Numerical and experimental investigation of a 100 PW, 800 nm OPCPA system employing guanidinium tetrafluoroborate

A novel nonlinear crystal named C(NH_2 )_3 BF_4 (GFB) has been reported with excellent performance in the ultraviolet range. This work presents theoretical simulations and verification experiments demonstrating the superior performance of GFB crystals in 800 nm OPCPA processes.

The results demonstrate that the GFB crystal can achieve broadband amplification with a spectral width of 150 nm centered at wavelength of 800 nm, while exhibiting an effective nonlinear coefficient of d_eff=1.7 pm/V. In the verification experiments, using a 526.5 nm laser as the pump, broadband amplification of 35 nm in the 800 nm central wavelength band was achieved based on GFB crystals. The results confirmed the broad amplification bandwidth of GFB crystals and their superior amplification efficiency compared to LBO crystals.