A tunable and single-longitudinal-mode Ho:YLF laser

• A 345 mW Ho:YLF laser operating on single-longitudinal-mode is reported.
• The intracavity etalon method is used to achieve tunable operation.
• The output wavelength can be tuned from 2051.6 nm to 2063.3 nm.
• A 1.94 μm Tm-doped fiber laser is used as pump source.

A 1.94 μm Tm-doped fiber laser pumped tunable single-longitudinal-mode Ho:YLF laser with double etalons was reported for the first time. The maximum single-longitudinal-mode output power of 345 mW at 2051.6 nm was achieved at the absorbed pump power of 11.9 W, corresponding to a slope efficiency of 5.5% and an optical conversion efficiency of 2.9%. By regulating the angle of the F–P etalons, the output wavelength of the laser can be tuned from 2051.6 nm to 2063.3 nm. The single-longitude-mode Ho:YLF laser operating at 2 μm can be used as the seed laser source of coherent Doppler lidar, differential absorption lidar and so on.