Fabrication of a Cr4+: YAG Crystal Fiber and its Use in a Mode-Locked All-Fiber Laser Source

An all-fiber Cr
⁴⁺
: YAG doped mode-locked laser is successfully developed at the first time. The results indicate a lasing threshold of 150 mW, maximum output power of 300 mW, a signal-to-noise ratio of 70-dB and a repetition frequency of 15.9 MHz. This is an important achievement because it shows that the Cr
⁴⁺
:YAG mode-locked laser has the potential to be used in spectral domain optical coherence tomography applications.