Stimulated Brillouin Scattering (SBS) and Other Nonlinear Suppression for High Power Fiber Delivery System for Navy Platform High Energy Laser (HEL)

The Navy is interested in the burgeoning technology area that supports a High-Energy Laser (HEL) system on naval platforms that can serve a vital role in naval defensive and offensive operations for ensuring Navy Battle Space Supremacy and water space management. Narrow-linewidth Yb-doped fiber lasers have attracted considerable attention over the past decade due their utility in beam combining architectures for further power scaling. This spectral condition along with the necessity to deliver up to 10kW of light in a single mode fiber over 60 feet result in unwanted non-linear effects. The main two among them are Stimulated Brillouin Scattering (SBS) and Stimulated Raman Scattering (SRS).  There are no commercial fibers available to provide high power transmission of narrow spectral width light of kW level single mode fiber lasers for distances of tens of meters. The Phase I demonstrated the feasibility of developing novel SBS suppressed fiber. During Phase II more fibers will be developed according to the advanced design with expected 10dB SBS suppression.