Development of rare-earth-doped large-core photonic bandgap fibre technology for power-scaling at challenging wavelengths

我提出了一项为期12个月的新型普通光纤技术的广泛研究项目，以在稀土掺杂的大芯子光子带隙光纤中提供波导滤波。虽然这项技术将使各种重要的光纤器件得以实现和改进，但本提案将专注于一种特定且特别有吸引力的器件，即一种工作在900 nm左右、可产生数十瓦平均功率水平的掺钕大芯光子带隙光纤激光器。目标是在这个光谱范围内打破目前的纪录功率水平。进一步的预期目标包括将功率扩展到更高的水平，以及更高程度的设备工作，例如基于所开发的光纤开发超快脉冲电源。这一建议利用了最近在芯区缩放(特别是掺Yb光纤光源)、二极管泵浦光源亮度的提高以及无源光子带隙光纤技术的进步方面取得的令人印象深刻的结果。如果成功，这项研究将带来紧凑、高效和可靠的光纤光源，可用于在生物成像和定向应用中取代钛蓝宝石激光器，并在倍频到蓝色后，可用于水下激光雷达系统以及大型激光显示器。与光纤开发相关的整体技术成果也可以扩展到其他稀土掺杂光纤，例如980 nm/1178 nm掺Yb光纤或约1.6微米的ErYb/Yb共掺光纤，所有这些光纤都存在1060~1090 nm的过度寄生发射，并且可以通过分布式光纤内过滤进行控制。

I propose an extensive twelve-month research project on novel generic fibre technology to provide waveguide filtering within rare-earth-doped large-core photonic bandgap fibres. Whilst this technology will enable and improve a wide range of important fibre devices, this proposal will focus on one specific and particularly attractive device, namely, a neodymium-doped large-core photonic bandgap fibre laser operating at around 900 nm generating multi-ten-W average power levels. The goal is to break the current record power level in this spectral range. Further prospective targets include power-scaling to even higher levels, and higher degrees of device work, e.g. the development of an ultrafast-pulse source based on the fibre developed. This proposal takes advantages of the recent impressive results on core area scaling, (of ytterbium-doped fibre sources in particular), increases in brightness of diode pump sources, as well as advances in passive photonic bandgap fibre technology. If successful, this research will lead to compact, efficient and reliable fibre sources that can be used to replace Ti:sapphire lasers in bio-imaging and targeting applications, and after frequency-doubling to the blue, can be used for under-water lidar systems as well as large-scale laser displays. The overall technology outcome related to fibre development can also be extended to other rare-earth-doped fibres, e.g. 980-nm/1178-nm ytterbium-doped fibres or around 1.6-micron erbium/ytterbium co-doped fibres, all of which also suffer from excessive parasitic emissions at 1060~1090 nm and that can be controlled through distributed in-fibre filtering.