Low-threshold and multi-wavelength Q-switched random erbium-doped fiber laser

We demonstrate a low-threshold and multi-wavelength Q-switched random fiber laser with erbium-doped fiber as the gain medium and Rayleigh scattering as the randomly distributed feedback. Q-switched pulses are generated with threshold as low as 27 mW by combining random cavity resonances and the Q-value modulation effect induced by stimulated Brillouin scattering. The repetition rate is typically on the kilohertz scale with rms timing jitter of < 5.5% and rms amplitude fluctuation of < 30%. Raman Stokes emissions up to the third order are observed with an overall energy of nearly 42% of the pulse output, which may open an avenue for applications requiring multiple wavelengths. (C) 2016 The Japan Society of Applied Physics