Graphitic Carbon Nitride Q-Switched Tm:CNNGG Laser at 2 Micrometer Wavelength Region

The Q-switching performance of graphitic carbon nitride (g-C3 N4) based on saturated absorption is demonstrated in 2 micrometer wavelength region for the first time. The g-C3N4 saturable absorbers, processed by thermal oxidation etching, are employed for passive Q-switching in a Tm:CNNGG laser. With a 5 hours long thermal oxidation etched g-C3N4 saturable absorber, the Q-switched Tm:CNNGG laser generates a shortest pulse duration of 132 ns with a repetition frequency of 16 kHz and a peak power of 98.5 W. The experimental results indicate that g-C3N4 is an excellent saturable absorber for passive Q-switching in 2 micrometer wavelength region.