Q-switching pulse generation in multi-wavelength Brillouin Erbium-doped Fiber laser

Stimulated Brillouin scattering (SBS) was successfully used to induce Q-switching operation in a multi-wavelength Brillouin Erbium fiber laser (BEFL) operating in a long-wavelength band (L-band) regime. The SBS based self Q-switched laser used a 4.5 long highly nonlinear Erbium-doped fiber (EDF) as the hybrid gain medium to generate a multiple wavelength Q-switched pulses, which operated at the center wavelength of around 1603 nm. By changing the input pump power in a range from 59.1 mW to 162.2 mW, the repetition rate can be varied from 14.29 to 29.69 kHz and the pulse width can be grasped from 26.52 to 14.80 μs. Under 162.2 mW pump power, the maximum pulse energy was recorded at 96.0 nJ and the signal to noise ratio of the fundamental radio frequency was measured to be as high as 52.73 dB, which indicates the excellent stability of the SBS-based Q-switched laser. To the best of our knowledge, this is the first experiment of realizing a BEFL with Q-switched multi-wavelength output without any physical saturable absorber devices.