Development of multi-kW Coherently Combined Fibre Master Oscillator Power Amplifiers

提出了Yb光纤主振荡器功率放大器（MOPAs）的开发，使相干组合激光束阵列的功率从多千瓦扩展到大于20千瓦。这与莱昂纳多公司的战略计划一致，即为一系列国防应用提供新颖而强大的激光技术。实现目标上的最高辐照度将得到kw级光纤MOPAs的开发和演示的支持，在1m波长，具有最高的效率和对影响空间和时间相干性的激光参数的最严格控制。在广泛的环境条件下进行无源和有源相位控制的最新技术将是这项工作的一个关键主题，为将大量光纤mopa （N bbb10）组合在一个最终系统中奠定基础，该系统对极端环境条件具有鲁棒性。此外，这项工作将包括通过应用神经网络开发先进的相位传感和自适应控制。光纤MOPAs的封装对优化放大器性能也很重要，因此提出了先进的制造和组装技术，并以高功率光纤激光建模和仿真为支持。该项目将以最高的效率将最先进的光纤放大器提升到多千瓦的功率水平。通过应用莱昂纳多和赫瑞瓦特大学最新的纤维组件、传感和计量技术，该项目具有新颖性。放大器将采用最新的先进封装方法，其中一个例子是使用光纤准直光束传输组件的玻璃-金属键合，这是赫瑞瓦特大学开发的。该提案包括神经网络在最先进的相干组合激光系统中的新应用。

Development of Yb fibre Master Oscillator Power Amplifiers (MOPAs) is proposed, to enable power scaling from multi-kW to greater than 20 kW in coherently combined laser beam arrays. This aligns with a Leonardo strategic plan to deliver novel and robust laser technology for a range of defense applications. Achieving the highest irradiance on target will be underpinned by the development and demonstration of kW-level fibre MOPAs, at 1m wavelength, with the highest efficiency and tightest control of laser parameters affecting spatial and temporal coherence.State of the art techniques for passive and active phase control under a wide range of environmental conditions will be a key theme of the work, laying the foundations for combining large numbers of fibre MOPAs (N > 10) in an eventual system which is robust against extreme environmental conditions. Further to this, the work will include scope for the development of advanced, phase sensing and adaptive control via the application of neural networks. Packaging of fibre MOPAs is also of importance for optimum amplifier performance and so advanced manufacturing and assembly techniques are proposed, supported by high-power fibre laser modelling and simulation.The project will advance state-of-the-art fibre amplifiers to multi-kW levels of power with the highest efficiency. Novelty is embedded within the project by the application of the latest fibre components, sensing and metrology techniques available within Leonardo and Heriot-Watt University. The amplifiers will exploit the latest advanced packaging methods and one example is the use of glass-to-metal bonding of fibre-collimated beam delivery assemblies, as developed at Heriot Watt University. The proposal includes a new application for neural networks within state-of-the-art coherently combined laser systems.