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

在材料激光加工、医学、传感和国防等领域，越来越多的应用需要在可见波长范围内工作的高功率激光器。不幸的是，访问该波长范围的传统方法与高功率水平的操作不兼容，因此需要一种不同的方法。本项目将结合包层泵浦光纤激光器在近红外波段的功率缩放优势和新颖的非线性频率转换方案，研究在可见光波段产生千瓦级激光功率的新策略。该方法提供了在整个可见波段以非常高的功率水平和高整体效率实现前所未有的波长覆盖的前景。该项目将包括对在非常高的功率水平下工作的频率转换光纤激光器的物理学进行详细研究，以建立功率缩放策略并确定基本限制。这将应用于在连续波和峰值功率脉冲模式下工作的包层泵浦光纤激光器，以最大限度地发挥应用潜力。该项目的总体目标是开发新一代可见光激光器，其性能水平远远超过目前工业激光加工中使用的最先进技术。

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.