L-band Wavelength-Switchable Dissipative Soliton Resonance Er-doped Fiber Laser

The experiment reports a kind of L-band dissipative soliton resonance (DSR) nanosecond Er-doped fiber laser. The passive mode-locked L-band DSR pulse is achieved in a figure-eight structure by using the nonlinear-amplifying-loop-mirror (NALM). The repetition rate of pulse is 468 kHz. At the maximum pump power of 398 mW, the output power is 25 mW with a pulse energy of 45 nJ. By adjustment of polarization state in cavity, the output pulse can be switched among 4 different DSR states with central wavelength of 1572, 1585, 1590 and 1605 nm discretely, presenting different peak power and pulse width. We can determine that the adjustment of polarization state changes the loss spectra of cavity and the 4 DSR states operate in different balance points. The tunable DSR pulse duration is from 120 to 150 ns by increasing the central wavelength.