Real-Time Observation of Mode Locking and Q -Switching in Erbium-Doped Fiber Laser Using Plasmonic Titanium Nitride Nanoparticles

As typical soliton pulse sources, ultrashort-pulse fiber lasers offer excellent platforms for the investigation of soliton dynamics. On the basis of dispersive Fourier transform, we report the pulse evolution and dynamics of a pulsed erbium-doped fiber laser with plasmonic titanium nitride nanoparticles under different pump powers in two states: mode-locking and Q -switched mode-locking (QS-ML). In the QSML regime, the real-time evolution spectra exhibit a regular periodic change that corresponds to the Q -switching rate. The results of this study may stimulate further exploration of metal nitride materials for pulse generation in fiber lasers, which have widespread applications in science and technology.