A Multi-Wavelength Brillouin Erbium Fiber Laser With Double Brillouin Frequency Spacing and Q-Switching Characteristics

A multiwavelength Brillouin Erbium fiber laser (MWBEFL) with double brillouin frequency spacing and Q-switching characteristics is demonstrated based on figure-of-eight configuration. The proposed MWBEFL uses a four-port circulator as a double-frequency shifter to isolate and circulate the odd-stokes signals through the Brillouin gain medium. Multiwavelength combs with 14 and 8 lasing lines and spacing of 0.16 nm are obtained by the use of 10-km long nonzero dispersion shifted fiber (NZDSF) and 2-km long dispersion compensating fiber (DCF), respectively. The Q-switched pulse trains are obtained in the proposed MWBEFL at 1480-nm pump power within 29 to 40 mW. It has repetition rates of 20.4 and 104.2 kHz with the corresponding pulse widths of 3.84 and 1.03 μs using the NZDSF and DCF, respectively, as the gain medium.