Development of innovative fiber lasers for biomedical, industrial and defense & security applications

光纤激光器与激光二极管沿着，极大地促进了新一代激光源的发展，并将其应用于人类活动的几乎所有领域。在制造业中，准衍射极限镱光纤激光源在1 µm波长下具有数十kW的输出功率，彻底改变了金属的切割和焊接。工作在1.5 μm的基于掺铒石英光纤的激光器和放大器也在全光通信网络的发展中发挥了关键作用。事实上，光纤激光器已经彻底改变了工业激光器，以至于一些专家现在预测，它们将在未来十年内完全淘汰固态激光器。在制造业领域，首先由德国和日本公司大规模引入的光纤激光器已经接管了焊接，精细钻孔和金属切割等业务。与它们所取代的固态激光器相比，它们坚固、紧凑且高度可靠。这些上级特性直接来源于光纤布拉格光栅（FBG）的物理特性。事实上，在单片（即全光纤）光纤激光器中使用FBG作为集成腔耦合器消除了所有机械不稳定性，从而极大地提高了其耐用性并大大减小了器件的整体尺寸。事实上，FBG确实是商业光纤激光器发展的关键部件。因此，该提案旨在支持与我们的工业合作伙伴进行有针对性的合作研究，旨在开发用于开发单片光纤激光器的最佳制造工艺，即波长为1 µm的高功率光纤激光器以及工作在2µm和4 µm之间的中红外光纤激光器。

Fiber lasers, along with laser diodes, have greatly contributed to the development of a new generation of laser sources as well as their applications in virtually every sector of human activity. In the manufacturing sector, quasi diffraction-limited ytterbium fiber laser sources with output power of the order of tens of kW at a wavelength of 1 µm have revolutionized cutting and welding of metals. Erbium-doped silica fiber-based lasers and amplifiers operating at 1.5 µm have also played a key role in the development of all-optical telecommunication networks. In fact, fibre lasers have completely revolutionized industrial lasers to such an extent that several experts are now forecasting that they will totally wipe out solid-state lasers within the next decade. In the manufacturing sector, fibre lasers, first introduced massively by German and Japanese companies, have already taken over operations such as welding, fine drilling and cutting of metals. Compared to the solid-state lasers that they have replaced, they are rugged, compact and highly reliable. Now, these superior features are directly derived from the physical properties of Fibre Bragg gratings (FBGs). In fact, the use of FBGs as integrated cavity couplers in Monolithic (i.e. all-fibre) fibre lasers eliminates all mechanical instability, thus tremendously improves its ruggedness and considerably reduces the device overall dimension. In fact, FBGs is truly the key component allowing for the development of commercial fibre lasers. This proposal therefore aims at supporting a targeted collaborative research effort with our industrial partners, aiming at the development of an optimal manufacturing process for the development of monolithic fibre lasers, namely high power fiber lasers at the wavelength 1 µm as well as Mid-Infrared fiber lasers operating between 2µm and 4 µm.