Speaker
Description
Thulium-doped silica fibre (TDF) lasers have a broad emission band near 2 $\mu$m, making them attractive for use with next-generation cryogenic-silicon gravitational wave detectors. We have demonstrated single-frequency, polarised 2 $\mu$m TDF distributed Bragg reflector (DBR) lasers at wavelengths between 1900 nm and 2050 nm. A high Tm concentration allows the use of a short cavity length, ensuring robust single-frequency operation whilst achieving high efficiency and output powers of up to 80 mW at 2050 nm. These DBR lasers would be suitable for use as a seed laser for further amplification to achieve the application requirements. We also describe a fibre laser mount that provides the thermal and mechanical stability required to achieve low-noise free-running operation.
