Numerical simulation of instantaneous propagation characteristics of a supercontinuum laser in marine atmospheric turbulence

In this study, we statistically investigated the instantaneous propagation characteristics of a supercontinuum (SC) laser in marine atmospheric turbulence, taking into account both the inner and outer scales of turbulence using the multiple phase screen method. The results indicate that under weak turbulence strength, both the inner and outer scales of turbulence significantly influence the scintillation characteristics of the SC laser, especially at longer transmission distances. The outer scale primarily causes beam wandering with minimal impact on beam spreading. As the outer scale increases, the phenomenon of beam wandering becomes more pronounced. Conversely, the inner scale has a more significant effect on beam spreading. A decrease in the inner scale intensifies beam spreading but has little to no effect on beam wandering. Additionally, compared to a monochromatic laser (ML), the SC laser shows no significant difference in terms of beam wandering and beam spreading effects. However, due to the combined effects of multi-wavelength smoothing and beam spreading, leading to spatial averaging, the SC laser source demonstrates a lower scintillation index than the ML, particularly at smaller inner scales. These results have a significant impact on the application and development of supercontinuum lasers in complex atmospheric environments.