Investigation of novel schemes for power scaling cladding-pumped fibre lasers in the visible wavelength regime

A growing number of applications in areas such laser processing of materials, medicine, sensing and defence require high power lasers operating in the visible wavelength band. Unfortunately, traditional methods for accessing this wavelength regime are not compatible with operation at high power levels and so a different approach is needed. This project will investigate a new strategy for generating kilowatt-class laser power in the visible band by combining the power-scaling advantages of cladding-pumped fibre lasers in the near-infrared band with novel nonlinear frequency conversion schemes. The approach offers the prospect of unprecedented wavelength coverage across the entire visible wavelength band at very high power levels and with high overall efficiency. The project will involve a detailed study into the physics of frequency-converted fibre lasers operated at very high power levels to establish a power scaling strategy and to determine the fundamental limits. This will be applied to cladding-pumped fibre lasers operating in continuous-wave and high-peak-power pulsed modes of operation to maximise the application potential. The overall ambition of the project will be a new generation of visible lasers boasting levels of performance well beyond the current state-of-the-art for use in industrial laser processing.