Four-wave-mixing assisted multi-wavelength short pulse generation in an erbium-doped-fiber laser based tellurium nanorod saturable absorber

Abstract We report on tellurium nanorods as a new type of saturable absorber (SA)-induced four-wave-mixing to construct an all-fiber multi-wavelength passively Q-switched erbium-doped-fiber laser. This proposed material is prepared via a green method of nanorod synthesis. The results show that the SA device simultaneously generates seven wavelengths within 1592.4–1599.6 nm waveband and mode spacing of 1.2 nm. Meanwhile, the Q-switched operation is attained with the minimum pulse width of 2.85 µs, maximum repetition rate is 44 kHz and maximum pulse energy of 50 nJ at 275 mW pump power. The number of the generated multi-wavelength lasing lines and the performance of Q-switched pulse fiber lasers have significant value for understanding the dynamics of laser physics and also have potential applications in different fields of photonics such as sensing, optical communication, optical metrology and spectroscopy.