Light sources and sensors in the mid-infrared (Mid-IR) are the subject of intensive research, as they enable key applications ranging from the monitoring of greenhouse gases and pollutants to optical frequency standards for navigation and timekeeping systems, as well as optical communications, LIDAR, and medical diagnostics and therapy. Progress in these fields critically depends on the availability of powerful, stable, and compact light sources.

Fibre-based Mid-IR lasers have emerged as promising coherent high-brightness sources for wavelengths beyond 2.5 µm and offer the potential to outperform established quantum cascade lasers. However, the effective use of suitable glass materials, such as fluoride glasses, requires a fundamental advancement of fibre fabrication and functionalisation techniques, as well as the development of the corresponding optical components. Only in this way can robust laser systems operating in the wavelength range of approximately 2.7 to 5 µm be realised.

The aim of this German–Australian project is the development of efficient and robust fibre-based laser components by the German consortium. These components will serve as modular building blocks for a fully fibre-integrated, flexible, and configurable laser source designed by the Australian partner group. The project focuses on erbium-doped ZBLAN fibre lasers for efficient emission at 2.8 and 3.5 µm.

The collaboration brings together complementary expertise in fibre fabrication, glass chemistry, laser physics, nonlinear optics, and fibre functionalisation, as well as access to specialised experimental methods and infrastructures on both sides. This provides the foundation for close scientific integration and sustainable synergies.

In addition, the project makes an important contribution to the qualification of early-career researchers. Research visits to the respective partner institutions enable the acquisition of a unique skill set at the interface of laser physics, materials science, and fibre optics. In the long term, the project supports the establishment of a lasting collaboration in the development of tailored Mid-IR light sources for sensing and imaging applications.