Wavelength tunable and amplitude-equilibrium dual-wavelength lasing sources with dual-pass Raman/Brillouin amplification configuration.

A simple technique for achieving wavelength tunable and amplitude-equilibrium dual-wavelength fiber laser source based on a dual-pass Raman/Brillouin amplification configuration is proposed and experimentally investigated. A stable room-temperature dual-wavelength lasing oscillations with average channel power of more than 1 mW and signal-to-noise ratio of more than 30 dB were obtained with only 250 mW Raman pump power. The dual-wavelength lasing oscillations with wavelength spacing of 0.076 nm were so stable that the maximum power fluctuations and wavelength shifts over more than 10 minutes of observation were less than 0.5 dB and 0.002 nm, respectively. The dual-wavelength lasing output can also be tuned in a range of ~35 nm from 1545.090 nm to 1580.078 nm with an amplitude-equilibrium of less than a peak power difference of 0.25 dB at the two wavelengths.