X-ray absorption spectroscopy for high performance rare-earth-doped fiber lasers

Important results from the project

The project has studied fiber laser materials from NKT Photonics, both as preforms and drawn fibers, with X-ray absorption spectroscopy at Balder, MAX IV, in Lund. The goal was to get increased knowledge of the local structure of the lasing ion, which directly affects efficiency and lifetime. The EXAFS results showed that the lasing ion is in a distorted coordination environment and that the structure is concentration dependent. The XANES results showed that the oxidation state is primarily 3+.

Expected long term effects

The project results, which are primarily structural insights, can in the future be correlated to fluorescence data and potentially provide both more efficient fiber lasers and fiber lasers with increased lifetime.

Approach and implementation

The project was divided into different activities: sample preparation, X-ray absorption spectroscopy measurements, X-ray absorption spectroscopy modeling and measurements with other techniques (Raman and fluorescence spectroscopy). Most activities went according to plan, but the most challenging technique was EXAFS, where the modeling work of the structure of the lasing ion took a large part of the project time. In summary, however, it has been a project that has given all partners new insights.

External links

Projektinfo på www.ri.se